0.87 grams of an 8% w/w progesterone gel must be mixed with 1.45 g of a 4% w/w progesterone gel to prepare a 2.32 g of 5.5% w/w gel
Let x represent the number of grams of an 8% w/w progesterone gel must be mixed with 1.45 g of a 4% w/w progesterone gel to prepare a (x + 1.45)g of 5.5% w/w gel
Hence:
(x * 8%) + (1.45 * 4%) = (x + 1.45) * 5.5%
0.08x + 0.058 = 0.055x + 0.07975
0.025x = 0.02175
x = 0.87 g
Find out more at: https://brainly.com/question/21105092
To prepare a 5.5% w/w progesterone gel, you should mix 4.383 g of an 8% progesterone gel with 1.45 g of a 4% progesterone gel.
Explanation:A weight/weight percent (w/w%) refers to the amount of a substance (in this case, progesterone) contained in a total solution. The equation we want to use here is 'mass of solute/mass of solution = concentration'. We know the concentrations of the individual gels and that of the final gel we want to achieve. We need to find out the amount of 8% gel to mix with 1.45 g of 4% gel to get a 5.5% gel.
This would be solved as follows:
Let's denote the weight of the 8% gel as x. The contribution of progesterone from the 8% gel is 0.08x, and from the 4% gel is 0.04*1.45 = 0.058 g. The total weight of the final gel solution is x+1.45 g. The total amount of progesterone is 0.08x + 0.058 g. To get a 5.5% solution, we set up the equation 0.08x + 0.058 / 1.45 + x = 0.055. Solving for x gives us 4.383 g.
Therefore, the answer is that 4.383 g of an 8% progesterone gel should be mixed with 1.45 g of the 4% gel to obtain a 5.5% gel.
Learn more about concentration calculation here:
https://brainly.com/question/17329736
#SPJ11
A liter of water was found to contain 10 mg of benzene (C6H6). What is the concentration of benzene in mg/L, ppm, and molarity?
The concentration of benzene is 10 mg/L or 10 ppm. To find molarity, we convert the mass of benzene to moles using its molar mass and then divide by the volume of the solution in liters. The molarity of the benzene is 1.28 x 10^-4 M.
Explanation:The concentration of benzene in the liter of water is 10 mg/L. This is because the question states that 10 mg of benzene is dissolved in one liter of water, and this is directly the concentration in mg per liter. To express this concentration in parts per million (ppm), we recall that 1 ppm is equivalent to 1 mg of substance per liter of water, since the density of water is approximately 1 g/mL, and there are 1000 g in a liter of water. Therefore, the concentration in ppm is also 10 ppm.
To calculate the molarity of benzene, we must first determine the molar mass of benzene, which is 78.11 g/mol (C6H6: 6 x 12.01 for carbon + 6 x 1.008 for hydrogen). The number of moles of benzene in 10 mg can be found using the formula: moles = mass (g) / molar mass (g/mol). Since we have 10 mg, we must first convert this to grams: 10 mg = 0.01 g. Thus, the number of moles of benzene is 0.01 g / 78.11 g/mol = 1.28 x 10-4 moles. Given that this is the amount in 1 liter, the molarity is 1.28 x 10-4 M.
Final answer:
The concentration of benzene is 10 mg/L, which is equivalent to 10 ppm as 1 L of water is approximately 1 kg. To find molarity, convert mass to moles using the molar mass of benzene, resulting in a molarity of 1.28 x 10⁻⁴ M for benzene in the solution.
Explanation:
The concentration of benzene in the water is already provided in mg/L, which is 10 mg/L. To express this concentration in parts per million (ppm), we use the fact that ppm is equivalent to mg/kg. Since the density of water is approximately 1.00 g/mL, 1 L of water weighs 1000 g, or 1 kg. Therefore, 10 mg of benzene in 1 kg of water is also 10 ppm.
To calculate the molarity of benzene (C₆H₆), we need the molar mass of benzene which is approximately 78.11 g/mol. Using the formula molarity = moles of solute / liters of solution, we first convert mg to grams: 10 mg = 0.010 g. The number of moles of benzene is calculated as 0.010 g / 78.11 g/mol which gives us 1.28 x 10⁻⁴ moles. Therefore, the molarity of benzene in the solution is 1.28 x 10⁻⁴ M.
Say, for example, that you had prepared a buffer c, in which you mixed 8.203 g of sodium acetate, nac2h3o2, with 100.0 ml of 1.0 m acetic acid. what would be the initial ph of buffer c? if you add 5.0 ml of 0.5 m naoh solution to 20.0 ml each of buffer b and buffer c, which buffer's ph would change less? explain
The initial pH of buffer C can be determined using the Henderson-Hasselbalch equation. Upon addition of NaOH, the buffer seeing less change in pH has greater buffer capacity, a measure of its resistance to pH changes upon addition of acid or base. Buffer solutions are most effective when the concentration of the weak acid and its conjugate base are equal.
Explanation:The topic you're dealing with pertains to buffer solutions in chemistry. In your given example with buffer C, you've mixed 8.203 g of sodium acetate with 100.0 ml of 1.0 M acetic acid. Here, the initial pH of the buffer can be calculated using the Henderson-Hasselbalch equation.
This equation states that pH = pKa + log([A-]/[HA]), where [A-] is the molar concentration of the base (sodium acetate) and [HA] is the molar concentration of the acid (acetic acid). You need to find the values of [A-] and [HA] and insert it in this formula to get the initial pH of buffer C.
Upon addition of NaOH solution to buffers B and C, the buffer whose pH changes less will be the one with the greater buffer capacity. This is because buffer capacity is a measure of the resistance of a buffer solution to pH change upon the addition of an acid or a base. Buffer capacity is maximized when [A-] = [HA], and a buffer solution loses its effectiveness when one component (either A- or HA) is less than about 10% of the other.
Learn more about Buffer solutions and pH here:https://brainly.com/question/30467257
#SPJ11
A student sets up the following equation to convert a measurement. (The stands for a number the student is going to calculate.) Fill in the missing part of this equation. pa * mm2
The question is incomplete, here is the complete question:
A student sets up the following equation to convert a measurement. (The stands for a number the student is going to calculate.) Fill in the missing part of this equation.
[tex]23.Pa.cm^3=?kPa.m^3[/tex]
Answer: The measurement after converting is [tex]23\times 10^{-9}kPa.m^3[/tex]
Explanation:
We are given:
A quantity having value [tex]23.Pa.cm^3[/tex]
To convert this into [tex]kPa.m^3[/tex], we need to use the conversion factors:
1 kPa = 1000 Pa
[tex]1m^3=10^6cm^3[/tex]
Converting the quantity into [tex]kPa.m^3[/tex], we get:
[tex]\Rightarrow 23.Pa.cm^3\times (\frac{1kPa}{1000Pa})\times (\frac{1m^3}{10^6cm^3})\\\\\Rightarrow 23\times 10^{-9}kPa.m^3[/tex]
Hence, the measurement after converting is [tex]23\times 10^{-9}kPa.m^3[/tex]
How did the growth of ideals of mass democracy, including such concerns as expanding suffrage, public education, abolitionism, and care for the needy affect political life and discourse?
It had an impact on democratically incompatible systems, and it forced people to address those problems.
What is democracy?Democracy is defined as a system of government where the populace has the power to decide legislation and debate issues. Supporting democracy helps build a more safe, stable, and affluent global environment where the United States may advance its national interests in addition to advancing such core American principles as worker rights and freedom of religion.
Democratically incompatible system is defined as a type of government where the people themselves hold the ultimate power and exercise it either directly or indirectly through a system of representation that often includes regular free elections. Democracy that is guided by a constitution. Deliberative democracy is a system in which the key to making moral decisions is real deliberation, not just voting.
Thus, it had an impact on democratically incompatible systems, and it forced people to address those problems.
To learn more about democracy, refer to the link below:
https://brainly.com/question/13158670
#SPJ5
Consider the chemical reaction :
????????H4 + ????????2 → c????????2 + ????H2????,
where ????, ????, c, and ???? are unknown positive integers. The reaction must be balanced; that is, the number of atoms of each element must be the same before and after the reaction. For example, because the number of oxygen atoms must remain the same, 2????=2c+????. While there are many possible choices for ????, ????, c, and ???? that balance the reaction, it is customary to use the smallest possible integers.
Balance this reaction.
The question is incomplete, here is the complete question:
Consider the chemical reaction:
[tex]aCH_4+bO_2\rightarrow cCO_2+dH_2O[/tex]
where a, b, c, and d are unknown positive integers. The reaction must be balanced; that is, the number of atoms of each element must be the same before and after the reaction. For example, because the number of oxygen atoms must remain the same, 2b=2c+d. While there are many possible choices for a, b, c, and d that balance the reaction, it is customary to use the smallest possible integers.
Balance this reaction.
Answer: The value of a, b, c and d in the given chemical equation are 1, 2, 1 and 2 respectively.
Explanation:
Law of conservation of mass states that mass can neither be created nor be destroyed but it can only be transformed from one form to another form.
This also means that total mass on the reactant side must be equal to the total mass on the product side.
For the given chemical reaction:
[tex]aCH_4+bO_2\rightarrow cCO_2+dH_2O[/tex]
On reactant side:
Number of carbon atoms = 1
Number of hydrogen atoms = 4
Number of oxygen atoms = 2
On product side:
Number of carbon atoms = 1
Number of hydrogen atoms = 2
Number of oxygen atoms = 3
We need to balance the number of hydrogen and oxygen atoms. So, the balanced equation for the given reaction becomes:
[tex]CH_4+2O_2\rightarrow CO_2+2H_2O[/tex]
Hence, the value of a, b, c and d in the given chemical equation are 1, 2, 1 and 2 respectively.
Refer to the section in the Background titled, "Standard Tests Gaseous Products." Use a flaming splint and a glowing splint to identify the gas above the liquid in the cup. Write the name and formula of the gas in the space provided
To identify the gas above the liquid in the cup, you can use a flaming splint and a glowing splint. If the gas supports combustion, it is oxygen.
Explanation:The gas above the liquid in the cup can be identified using a flaming splint and a glowing splint. If the gas supports combustion and allows the flaming splint to burst into full flame, it is oxygen. If the gas extinguishes the glowing splint, it is a gas that does not contain oxygen. Oxygen is the only gas that will support combustion.
6. What is the electric potential energy of a +3.0 μC charge placed at corner A?
The question is incomplete. The complete question is stated below:
Two point charges are held at the corners of a rectangle as shown in the figure. The lengths of sides of the rectangle are 0.050 m and 0.150 m. Assume that the electric potential is defined to be zero at infinity.
a. Determine the electric potential at corner A.
b. What is the electric potential energy of a +3 µC charge placed at corner A?
Answer / Explanation:
a )V(A) = 1 / 4πe° ( - 5 5x10∧6C / 0.150m + 2x10∧6C / 0.050m )
The answer to the equation above is : = +6.0x10∧4 j/c
b) U(A) = qV(A)= (3.0x10∧6C) (6.0x10∧4 . j/c) =
The answer to the equation above is : =0.18 J
Explanation:
Where V(A) is equivalent to the electric potential
U(A) is equivalent to the electric potential energy
Final answer:
Explanation of electric potential energy in physics.
Explanation:
Electric potential energy is the energy a charge possesses due to its position in an electric field. It is given by the formula U = k * Q1 * Q2 / r, where k is Coulomb's constant, Q1 and Q2 are the charges, and r is the distance between them.
)V(A) = 1 / 4πe° ( - 5 5x10∧6C / 0.150m + 2x10∧6C / 0.050m )
The answer to the equation above is : = +6.0x10∧4 j/c
b) U(A) = qV(A)= (3.0x10∧6C) (6.0x10∧4 . j/c) =
The answer to the equation above is : =0.18 J
The proper solvent choice is crucial for effective recrystallization.
What are the features of a good recrystallization solvent?
a)The solvent should dissolve a moderate quantity of the target substance near its boiling point but only a small quantity near 0 °C.
b)The solvent should not react with the target substance.
c)The crude compound should be soluble in this solvent at room temperature.
d)The solvent should be easily removed from the purified product.
e)The solvent should have a high boiling point.
Answer: option A. The solvent should dissolve a moderate quantity of the target substance near its boiling point but only a small quantity near 0 °C
Explanation:
Final answer:
A good recrystallization solvent should dissolve the substance near its boiling point but not at low temperatures, must not react with the substance, should be easily removed post-process, and ideally, should have a low boiling point to prevent 'oiling out'.
Explanation:
Features of a Good Recrystallization Solvent
The process of recrystallization is integral to purifying solid compounds in chemistry, and the choice of solvent is critical for its success. A good recrystallization solvent should have the following features:
The solvent should dissolve a significant quantity of the target substance near its boiling point and only a minimal quantity near 0 °C, allowing for recrystallization upon cooling.The solvent should not react with the target substance, thereby preventing chemical changes during the process.The crude compound should be insoluble in the solvent at room temperature; this ensures that the compound remains undissolved until heated.Following the recrystallization, the solvent should be easily removed from the purified product, typically via evaporation due to its relatively low boiling point.While a high boiling point is not ideal, the solvent's boiling point should be sufficient to dissolve the substance when heated.Additionally, ideal solvents are usually unreactive, inexpensive, and have low toxicity. Using a solvent with a relatively low boiling point is preferable as it reduces the chance of the compound 'oiling out' during the process, which can interfere with crystal formation. Mixed solvents can be used when no single solvent meets all criteria, though a single solvent is often best to maintain consistent solubility conditions.
When 10.51 g CaCO3 reacts with excess hydrochloric acid, as below, 3.29 g of CO2 is produced.
CaCO3(s) + HCl(aq) → CO2(g) + CaCl2(aq) + H2O(l)
What is the percent yield of CO2?
Answer:
71.2 %
Explanation:
This is a problem we can solve by making use of the stoichiometry of the balanced ( very important !) chemical reaction:
CaCO3(s) + 2HCl(aq) → CO2(g) + CaCl2(aq) + H2O(l)
Now determine the moles of CaCO3 and CO2 and perform the calculations
# mol CaCO3 = 10.51 g / 100.09 g/mol = 0.105 mol
From the stoichiometry of the reaction, we know 1 mol CO2 is produced per mol of CaCO3, thus whe should expect
0.105 mol CaCO3 x 1 mol CO2/ mol CaCO3 = 0.105 mol
lets compare this theoretical value with the one obtained:
mol CO2 obtained = 3.29 g / 44 g/mol = 0.075
Therefore our yield is
(0.075mol / 0.105 mol) x 100 = 71.2 %
By your calculations, you should administer 2.46 mL. What amount will you draw up in the syringe?
Answer:
The syringe should be at 2.50
Final answer:
To administer a 2.46 mL dose, draw up slightly more than this amount into the syringe and then adjust to the precise volume by expelling any excess. Ensure the plunger aligns with the 2.46 mL marking on the syringe for an accurate dose.
Explanation:
When administering medication in a clinical setting, it's important to measure the dosage accurately. If you've calculated that the correct dose is 2.46 mL, you should first draw up the liquid into the syringe to a volume slightly greater than needed, then carefully adjust down to the exact amount. For instance, you might withdraw 3-4 mL and then expel the excess until you have the precise 2.46 mL required for administration.
The technique of drawing up more than needed and then adjusting allows for removing air bubbles and ensuring an accurate dose. In practice, syringes often have volume marks in increments of 0.1 mL or 0.01 mL, depending on the syringe size. It is critical to use these markings and ensure that the top of the plunger aligns exactly with the marking for 2.46 mL when viewed at eye level.
A student heats 2.796g of zinc powder with 2.414g of sulphur.He reported that he obtained 4.169g of zinc sulfide and recover 1.041g of unreacted sulfur.
Show by calculation whether or not his results obey the law of conversation of mass
Answer:
The mass of reactants and products are equal hence the reaction obeys law of conservation of mass
Explanation:
The law of mass conservation states that for a closed system to all transfer of mass, the mass of system must remain constant over time. This means for a chemical reaction, the mass of reactants must equal the mass of products.
if 2.796g of Zn reacts with 2.414g of sulphur to produce 4.169g of ZnS ad 1.041g of unreacted sulphur, then it means that accorfing to the law of mass conservation, the mass of reactants (zinc and sulphur), must be equal to mass of products (zinc sulfide and unreacted sulphur)
Mass of reactants = 2.796g + 2.414g =5.21g
Mass of products = 4.169g + 1.041g=5.21g
In accordance with the Law of Conservation of Mass, the total mass of the reactants (5.21g) is equal to the total mass of the products (5.21g). Therefore, the student's results obey the Law of Conservation of Mass.
Explanation:The Law of Conservation of Mass states that matter can neither be created nor destroyed. Therefore, the total mass of the reactants should be equal to the total mass of the products in a chemical reaction.
Let's add up the mass of the reactants:
Zinc: 2.796gSulphur: 2.414gTotal mass of reactants = 2.796g + 2.414g = 5.21g
Now, let's add up the mass of the products:
Zinc sulfide: 4.169gUnreacted sulphur: 1.041gTotal mass of products = 4.169g + 1.041g = 5.21g
As we can see, the total mass of the reactants is indeed equal to the total mass of the products. Thus, the student's results obey the Law of Conservation of Mass.
Learn more about Law of Conservation of Mass here:https://brainly.com/question/32183542
#SPJ3
Calculate the percent error of your average specific heat as compared to the accepted values listed.Report your answer to the correct number of significant figures. This may be 2 or 3 significant figures. Csp(Pb) = 0.128 J/goC; Csp(Al) = 0.900 J/goC; Csp(Cu) = 0.387 J/goC % Error =
Answer:
%Error for Al = 2.23
%Error for Cu=2.65
%Error for Pb= 1.59
Explanation:
Percentage error is the difference between a measured value and a true value as expressed in percent.
%Error =( True value - measured value )/True value ×100
If the measured value is less than true value
%Error = ( Measured value - True value) / True value × 100
If the measured value is greater than true value
For Pb, true value = 0.126J/g•C
Measured value =0.128J/g•C
%Error= (0.128-0.126)/0.126 ×100= 1.57
For Cu, true value = 0.377J/g•C
Measured value = 0.387J/g•C
%Error = (0.387-0.377)/0.377 ×100 =2.65
For Al, True value = 0.921J/g•C
Measured value = 0.900J/g•C
%Error= (0.921-0.900)/0.921 ×100 =2.23
write a net ionic equation for the reaction of aqueous acetic acid and aqueous potassium hydroxide
Answer:
[tex]CH_{3}CO_{2}H(aq.)+OH^{-}(aq.)\rightarrow CH_{3}CO_{2}^{-}(aq.)+H_{2}O(l)[/tex]
Explanation:
Acetic acid is an weak acid. Therefore it does not dissociate completely in aqueous solution.
Potassium hydroxide is a strong base. Therefore it dissociates completely in aqueous solution.
An acid-base reaction occurs between acetic acid and potassium hydroxide.
Molecular equation: [tex]CH_{3}CO_{2}H(aq.)+KOH(aq.)\rightarrow KCH_{3}CO_{2}(aq.)+H_{2}O(l)[/tex]
Total ionic: [tex]CH_{3}CO_{2}H(aq.)+K^{+}(aq.)+OH^{-}(aq.)\rightarrow K^{+}(aq.)+CH_{3}CO_{2}^{-}(aq.)+H_{2}O(l)[/tex]
Net ionic:[tex]CH_{3}CO_{2}H(aq.)+OH^{-}(aq.)\rightarrow CH_{3}CO_{2}^{-}(aq.)+H_{2}O(l)[/tex]
The net ionic equation for the reaction between aqueous acetic acid (CH3COOH) and aqueous potassium hydroxide (KOH) is CH3COOH + OH- --> CH3COO- + H2O. The K+ ions are spectator ions and thus removed from the net ionic equation.
Explanation:To write a net ionic equation, we need to first balance the chemical reaction equation and then omit the spectator ions to get the net ionic equation. The balanced chemical reaction between aqueous acetic acid (CH3COOH) and aqueous potassium hydroxide (KOH) is: CH3COOH + KOH --> CH3COOK + H2O. After balancing the equation, we split the compounds into their ions: CH3COOH + K+ + OH- --> K+ + CH3COO- + H2O. Because K+ ions are present at both sides of the equation, they can be considered as spectators and therefore removed from our net ionic equation. Thus, the net ionic equation for the reaction is: CH3COOH + OH- --> CH3COO- + H2O.
Learn more about Net Ionic Equation here:https://brainly.com/question/36522237
#SPJ3
As an EPA scientist studying catalytic converters and urban smog, you want to find Kc for the following reaction: 2 NO2 (g) ⇋ N2(g) + 2 O2(g) Kc = ?? Use the following data to find the unknown Kc:
1/2 N2 (g) + 1/2 O2 (g) ⇋ NO (g) Kc = 0.004
2NO2 (g) ⇋ 2NO (g) + O2 (g) Kc = 0.056
Answer:
3500
Explanation:
The equilibrium constant of the reaction which has to be calculated is:-
2 NO2 (g) ⇋ N2(g) + 2 O2(g)
The given chemical equation follows:
1/2 N2 (g) + 1/2 O2 (g) ⇋ NO (g)
The equilibrium constant for the above equation is 0.004.
We need to calculate the equilibrium constant for the reverse equation of above chemical equation and also double of the above chemical equation, which is:
2NO (g) ⇋ N2 (g) + O2 (g)
The equilibrium constant for the reverse double reaction will be the reciprocal of the initial reaction.
If the equation is multiplied by a factor of '2', the equilibrium constant of the reverse reaction will be the square of the equilibrium constant of initial reaction.
The value of equilibrium constant for reverse reaction is:
[tex]K_{eq}'=(\frac{1}{0.004})^2[/tex] = 62500
The given chemical equation follows:
2NO2 (g) ⇋ 2NO (g) + O2 (g)
The equilibrium constant for the above equation is 0.056.
Thus, adding the both reaction gives the original reaction. So, equilibrium constant is:- 62500 x 0.056 = 3500
Final answer:
By manipulating and combining the equilibrium constants of related reactions, we find that the Kc for the reaction 2 NO2 (g) ⇋ N2(g) + 2 O2(g) is approximately 3500.
Explanation:
To calculate the equilibrium constant Kc for the reaction 2 NO2 (g) ⇌ N2(g) + 2 O2(g), we need to relate it to the known Kc values of the related reactions:
1/2 N2 (g) + 1/2 O2 (g) ⇌ NO (g), Kc = 0.0042NO2 (g) ⇌ 2NO (g) + O2 (g), Kc = 0.056To find the Kc for the desired reaction, we use the concept of reaction quotients, where the product of the equilibrium constants of two related reactions that gives the target reaction when added together, equals the equilibrium constant of the target reaction. Mathematically, if the second reaction is reversed, its Kc is inverted. Then we can combine the two equations:
The equilibrium constant for the reverse double reaction will be the reciprocal of the initial reaction.
If the equation is multiplied by a factor of '2', the equilibrium constant of the reverse reaction will be the square of the equilibrium constant of initial reaction.
The value of equilibrium constant for reverse reaction is
K_(eq)'=((1)/(0.004))^2 = 62500
The given chemical equation follows:
2NO2 (g) ⇋ 2NO (g) + O2 (g)
The equilibrium constant for the above equation is 0.056.
Thus, adding the both reaction gives the original reaction. So, equilibrium constant is:- 62500 x 0.056 = 3500
A mass of 34.05 g of H2O(s) at 273 K is dropped into 185 g of H2O(l) at 310. K in an insulated container at 1 bar of pressure. Calculate the temperature of the system once equi- librium has been reached. Assume that CP, m for H2O is con- stant at its values for 298 K throughout the temperature range of interest.
Answer:
The temperature of the system once equilibrium is reached, is 292 Kelvin
Explanation:
Step 1: Data given
Mass of H2O = 34.05 grams
⇒ temperature = 273 K
Mass of H2O at 310 K = 185 grams
Pressure = 1 bar = 0.9869 atm
Step 2: Calculate the final temperature
n(ice)*ΔH(ice fusion) + n(ice)*CP(H2O)(Tfinal- Ti,ice) + n(H20)*CP(H2O)*(Tfinal-Ti,H2O) = 0
Tfinal = [n(ice)*CP(ice)*Ti(ice) + n(H2O)*CP(H2O)*Ti(H20) - n(ice)*ΔH(ice fusion)] / [n(ice)*CP(ice) +n(H2O)*CP(H2O)]
⇒ with n(ice) = moles of ice = 34.05 grams / 18.02 g/mol = 1.890 moles
⇒ with CP(ice) = 75.3 J/K*mol
⇒ with Ti(ice) = the initial temperature of ice = 273 K
⇒ with n(H2O) = the moles of water = 185.0 grams / 18.02 g/mol = 10.27 moles
⇒ with CP(H2O) = CP(ice) = 75.3 J/K*mol
⇒ with Ti(H2O) = the initial temperature of the water = 310 K
⇒ with ΔH(ice, fusion) = 6010 J/mol
Tfinal = [1.890 moles * 75.3 J/K*mol * 273 + 10.27 mol * 75.3 J/K*mol * 310 K - 1.890 moles * 6010 J/mol] / [1.890 moles *75.3J/k*mol + 10.27 mol * 75.3 J/K*mol]
38852.541 + 239732.61 - 11358.9 = 267226.251
Tfinal= 291.8 ≈ 292 Kelvin
The temperature of the system once equilibrium is reached, is 292 Kelvin
We must use the principle of conservation of energy to equate the heat gained by the ice to the heat lost by the water, in a given equation, to calculate the final equilibrium temperature.
Explanation:The topic here is thermodynamics, specifically calculating the final equilibrium temperature when two substances are mixed. Given the information, we can apply the principle of conservation of energy, which in this context is the heat gained by one substance is equal to the heat lost by the other. In this case, the heat gained by the ice (H2O(s)) as it melts and increases in temperature is equal to the heat lost by the water (H2O(l)). Therefore, we have the equation 34.05 g * 1 kcal/kg * K *(T - 273 K) + 34.05 g * 80 Cal/g = 185 g * 1 kcal/kg*K *(310 K - T) where T is the final temperature to be solved.
Learn more about heat transfer here:https://brainly.com/question/34419089
#SPJ3
Define lower end and upper end of a melting point range. (Select all that apply)
O The lower end is the temp at which liquid first appears.
O The upper end is the temp at which liquid first appears.
O The upper end is the temp at which the last trace of crystals disppears.
O The lower end is the temp at which the last trace of crystals disppears.
Answer:
The lower end is the temp at which liquid first appearsThe upper end is the temp at which the last trace of crystals disappearExplanation:
Melting range is one of the properties of solid that can help to identify its purity. It is necessary to note the whole range of temperature through which the transition takes place. The change in this range of melting temperature is indicative of impurity in the sample.
The lower end is the starting temperature at which solid starts to melt while the upper end is the temperature at which the last trace of solid converts to liquid.
For a reaction at equilibrium, which of the following is the best way to think about it?
a. forward rate = reverse rate
b. The concentration of intermediates becomes negligible.
c. The concentration of reactants becomes negligible.
d. The concentration of reactants = concentration of products.
e. The concentration of reactants and products are not related.
Answer: Option A. forward rate = reverse rate
Explanation: for a system to be in dynamic equilibrium, it means that the rate of formation of product is the same as the rate of formation of reactant.
. In chemistry, one often uses a unit of charge known as the Faraday, F, which has the magnitude of the charge of 1 mole of electrons. How many Coulombs are there in a Faraday
Answer: 96500 Coulombs are there in a Faraday.
Explanation:-
It is given that 1 mole of electrons has charge of 1 Faraday.
Moles of electron = 1 mole
According to mole concept:
1 mole of an atom contains [tex]6.022\times 10^{23}[/tex] number of particles.
We know that:
Charge on 1 electron = [tex]1.6\times 10^{-19}C[/tex]
Charge on 1 mole of electrons = [tex]1.6\times 10^{-19}\times 6.022\times 10^{23}=96500C[/tex]
Thus 96500 C= 1 Faraday
Thus 96500 Coulombs are there in a Faraday.
There are approximately 96,485.33289 Coulombs in one Faraday.
The Faraday constant, denoted by F, is the charge of one mole of electrons. It is a fundamental physical constant with a value that has been experimentally determined. The Faraday constant is defined as the amount of charge carried by one mole of electrons, and its value is approximately 96,485.33289 Coulombs per mole.
The relationship between the Faraday constant and the charge in Coulombs can be expressed as:
[tex]\[ 1 \text{ Faraday} = 1 \text{ mole of electrons} \times \frac{6.022 \times 10^{23} \text{ electrons}}{1 \text{ mole of electrons}} \times \frac{1.602 \times 10^{-19} \text{ Coulombs}}{1 \text{ electron}} \][/tex]
Here, [tex]\(6.022 \times 10^{23}\)[/tex] is Avogadro's number, which is the number of particles (in this case, electrons) per mole, and [tex]\(1.602 \times 10^{-19}\)[/tex] is the elementary charge, which is the charge of a single electron in Coulombs.
Multiplying these values together gives:
[tex]\[ 1 \text{ Faraday} = 6.022 \times 10^{23} \times 1.602 \times 10^{-19} \text{ Coulombs} \] \[ 1 \text{ Faraday} = 96,485.33289 \text{ Coulombs} \][/tex]
Therefore, one Faraday is equivalent to approximately 96,485.33289 Coulombs. This is the standard value used in chemistry and physics for calculations involving the charge of electrons on a molar scale.
A solution is made by mixing 36. g of heptane (C_7H_16) and 16. g of chloroform (CHCl_3). Calculate the mole fraction of heptane in this sol'. Be sure your answer has the correct number of significant digits.
Answer:
Mole fraction of solute (heptane) → 0.73
Explanation:
Mole fraction = Moles of solute or solvent / Total moles
Let's calculate the moles of everything:
Moles of solute → Mass of solute / Molar mass
36 g / 100 g/mol = 0.36 moles
Moles of solvent → Mass of solvent / Molar mass
16 g / 119.35 g/mol = 0.134 moles
Total moles = 0.36 + 0.134 = 0.494 moles
Mole fraction of solute = 0.36 / 0.494 → 0.73
The compound zoapatanol was isolated from the leaves of a Mexican plant.
Classify each oxygen in zoapatanol according to the functional group to which it belongs. If an oxygen is part of an alcohol, classify the alcohol as primary, secondary, or tertiary.
Answer:
The structure is shown below!
1. Ketone
2. Secondary alcohol
3. Ether
4. Primary alcohol
Explanation:
The molecule of zoapatanol is shown below, each oxygen is marked by a number. The functional group represents the organic function of the substance. Some substances can have more than one function.
The oxygen is presented in several organic compounds, such as alcohol, aldehyde, ketone, ether, ester, carboxyl acid, and others. The structure of each is different, so an alcohol has the oxygen bonded to a carbon and to a hydrogen (called hydroxyl); an aldehyde has the oxygen bonded to a terminal carbon; a ketone has the oxygen bonded to nonterminal carbon; the ether has an oxygen between carbons; the ester has an oxygen between carbons, and one of these carbons has a double bond with other oxygen, and a carboxyl acid has the terminal carbon bonded to an oxygen and to a hydroxyl.
If the hydroxyl is bonded to a primary carbon (which is bonded to only one carbon), then it's a primary alcohol, if it's bonded to a secondary carbon (which is bonded to 2 carbons), then it's a secondary alcohol, and if it's bonded to a tertiary carbon (which is bonded to 3 carbons), then it's a tertiary alcohol.
Analyzing the structure, the oxygens are:
1. Ketone
2. Secondary alcohol
3. Ether
4. Primary alcohol
Calculate the molality of a solution formed by adding 4.40 g NH4Cl to 11.0 g of water.
To calculate the molality of a solution, divide the moles of solute by the mass of solvent (in kg). In this case, the molality of the NH4Cl solution is 7.45 m.
To calculate the molality of a solution, we need to first calculate the moles of NH4Cl and water.
Calculate the moles of NH4Cl by dividing the given mass by the molar mass of NH4Cl (53.49 g/mol): 4.40 g NH4Cl / 53.49 g/mol = 0.082 mol NH4Cl.
Calculate the moles of water by dividing the given mass by the molar mass of water (18.015 g/mol): 11.0 g H2O / 18.015 g/mol = 0.61 mol H2O.
Now we can calculate the molality using the moles of solute and the mass of the solvent:
Molality = moles of solute / mass of solvent (in kg)
Molality = 0.082 mol NH4Cl / 0.011 kg H2O = 7.45 m NH4Cl.
For more such question on molality visit:
https://brainly.com/question/13200956
#SPJ3
Calculate the mass of butane needed to produce 59.8 g of carbon dioxide. Express your answer to three digits and include the appropriate units.
Answer:
We need 19.8 grams of butane
Explanation:
Step 1: Data given
Mass of CO2 produced = 59.8 grams
Molar mass CO2 = 44.01 g/mol
Molar mass butane = 58.12 g/mol
Step 2: The balanced equation
2 C4H10 + 13 O2 → 8 CO2 + 10 H2O
Step 3: Caclulate moles CO2
Moles CO2 = mass CO2 / Molar mass CO2
Moles CO2 = 59.8 grams / 44.01 g/mol
Moles CO2 = 1.36 moles
Step 4: Calculate moles butane
For 2 moles butane we need 13 moles O2 to produce 8 moles CO2 and 10 moles H2O
For 1.36 moles CO2 we need 1.36/4 = 0.34 moles butane
Step 5: Calculate mass butane
Mass butane = moles butane * molar mass butane
Mass butane = 0.34 moles * 58.12 g/mol
Mass butane = 19.76 grams ≈ 19.8 grams
We need 19.8 grams of butane
Alka-Seltzer® is an antacid. One of its active ingredients is NAHCO3. Write out an equation to show how Alka-Seltzer® neutralizes stomach acids (HCl).
Answer:
NaHCO3 + HCl --> NaCl + CO2 + H2O
Explanation:
NaHCO3 which is an acidic salt because of the replaceable H+ (Bronste lowry acid), by definition acid dissociates in water to release a proton.
NaHCO3 dissociates in water to give Na+, H3O+ and HCO3-
Stomach acid which is HCl also dissociates in water to give H3O+ and Cl-
The H3O+ and HCO3- combines briefly to form a weak carbonic acid almost immediately, which then further dissociates to form H2O and CO2. CO2 is burped out from the mouth.
Na+ and Cl- combines to form NaCl in water which is a table salt solution.
Below is an attachment containing the step by step reactions
One of the ingredients in Alka-Seltzer, sodium bicarbonate, reacts with stomach acid (HCl) to produce salt, water, and carbon dioxide, neutralizing the acid. This is represented by the equation NAHCO3 + HCl -> NaCl + H2O + CO2.
Explanation:The antacid Alka-Seltzer® contains an active ingredient called NAHCO3, also known as sodium bicarbonate. When Alka-Seltzer is taken, the sodium bicarbonate reacts with the stomach acid, or hydrochloric acid (HCl), to neutralize it. This chemical reaction can be represented by the equation: NAHCO3 + HCl -> NaCl + H2O + CO2. Thus, Alka-Seltzer works to relieve symptoms caused by excess stomach acid by producing salt, water, and carbon dioxide.
Learn more about Alka-Seltzer Neutralizing Acid here:https://brainly.com/question/32758314
#SPJ3
Select all that apply:
A)The mass ratio of oxygen to carbon in CO is twice the mass ratio of oxygen to carbon in CO2.
B)The mass ratio of oxygen to carbon in CO is 1.33 for every sample of CO.
C)mass ratio of oxygen to carbon in CO2 is 2.667 for every sample of CO2.
D)For two compounds of C and O, the mass ratio of C to O in one compound is a multiple of the mass ratio of C to O in the other compound.
Option B, C and D are correct.
Explanation:Carbon is a non metallic element with the atomic number 6 and mass number 12. Whereas oxygen is also a non metallic element with the atomic number 8 and mass number of 16.
In carbon monoxide, the mass ratio of oxygen to carbon is 16:12 =1.33. This ratio is same for every sample of carbon monoxide, because carbon monoxide has the universal formula of CO.
Similarly In carbon dioxide , the mass ratio of oxygen to carbon is 32:12 =2.667. This ratio is same for every sample of carbon dioxide, because carbon dioxide has the universal formula of [tex]CO_2[/tex].
Even we can see that the mass ratio of oxygen to carbon in carbon dioxide is just twice the mass ratio of oxygen to carbon in carbon monoxide, because of presence of twice as much as oxygen per molecule of carbon dioxide than carbon monoxide.
All of the following statements concerning voltaic cells are true EXCEPT
1) oxidation occurs at the cathode.
2) a salt bridge allows cations and anions to move between the half-cells.
3) electrons flow from the anode to the cathode in the external circuit.
4) a voltaic cell can be used as a source of energy.
5) a voltaic cell consists of two-half cells.
Answer:
oxidation occurs at the cathode.
Explanation:
In a voltaic cell electrons move from anode to cathode. At the anode, species give up electrons. This is an oxidation reaction depicted by the oxidation half equation. At the cathode, species accept electrons and become reduced. This is depicted by the reduction half equation. In summary; in a Voltaic cell, oxidation occurs at the anode while reduction occurs at the cathode.
In a voltaic cell, oxidation does not occur at the cathode.
A voltaic cell is an electrochemical cell that converts chemical energy to electrical energy, hence it can be used as a source of energy. It consists of two separate half-cells. There is a salt bridge between the two half cells allowing for the free flow of ions from one cell to another.
There are two electrodes, the anode undergoes oxidation and the cathode undergoes reduction. Electrons flow from the anode to the cathode.
Find out more at: https://brainly.com/question/1370699
The following reaction takes place at high temperatures.
Solid chromium(III) oxide reacts with liquid aluminum to give liquid chromium and liquid aluminum oxide.
Write a balanced chemical equation (include the states of matter).
Answer:
[tex]Cr_2O_3 (s) + 2Al (l)[/tex] ⇒ [tex]2Cr (l) + Al_2O_3 (l)[/tex]
The balanced chemical equation (including the states of matter) is
Cr₂O₃(s) + 2Al(l) ⇒ 2Cr(l) + Al₂O₃(l)
Solid chromium(III) oxide reacts with liquid aluminum to give liquid
chromium and liquid aluminum oxide. This reaction occurs at high
temperature because the reactivity is increased under this condition.
TYhe liquid aluminium is oxidized to form liquid aluminum oxide and the
Solid chromium(III) oxide is reduced to form liquid chromium and can be
referred to as a redox reaction.
Read more about Redox reaction here https://brainly.com/question/21851295
Zinc metal reacts with silver nitrate according to the reaction:
Zn(s) + 2AgNO3(aq)Zn(NO3 )2 (aq) + 2Ag(s)
Calculate the mass of Ag that forms when 3.00g of zinc metal is placed in an aqueous solution containing 3.75g of silver nitrate?
Answer: 2.38 grams of silver forms when 3.00g of zinc metal is placed in an aqueous solution containing 3.75g of silver nitrate.
Explanation:
To calculate the number of moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ....(1)
[tex]\text{Number of moles of zinc}=\frac{3.00g}{65g/mol}=0.0462mol[/tex]
[tex]\text{Number of moles of silver nitrate}=\frac{3.75g}{170g/mol}=0.0220mol[/tex]
The chemical equation is:
[tex]Zn(s)+2AgNO_3(aq)\rightarrow Zn(NO_3)_2(aq)+1Ag(s)[/tex]
By stoichiometry of the reaction;
2 moles of silver nitrate reacts with 1 mole of zinc
Thus 0.0220 moles silver nitrate react with=[tex]\frac{1}{2}\times 0.0220=0.0110[/tex] moles of zinc
Thus silver nitrate will acts as limiting reagent and zinc acts as excess reagent.
2 moles of silver nitrate produces 2 mole of silver
Thus 0.0220 moles silver nitrate react with=[tex]\frac{2}{2}\times 0.0220=0.0220[/tex] moles of silver
[tex]0.0220mol=\frac{\text{Mass of silver}}{108g/mol}\\\\\text{Mass of silver}=2.38g[/tex]
Thus 2.38 grams of silver forms when 3.00g of zinc metal is placed in an aqueous solution containing 3.75g of silver nitrate.
Draw the mechanism of polymerization of propylene with benzoyl peroxide. Show chemical structures and arrows and remember that radical stability is similar to carbocation stability. Thus, 3° radicals are more stable than 2° and so on.
Answer:
See explanation below
Explanation:
This mechanism of polimerization is of one type. This mechanism goes through free radical polimerization, which means that we use a initiator as the radical source, then, the polimerization begins with the breaking of the covalent bonds of that initiator. In this case the benzoyl peroxide. And this mechanism is given in three steps.
In the picture you have the mechanism in the 3 steps:
Benzyl ethyl ether reacts with concentrated aqueous HI to form two initial organic products (A and B). Further reaction of product B with HI produces organic product C. Draw the structures of these three products.
Answer:
See answer for details
Explanation:
In this case, we have the following substract:
Ph-CH2 - O - CH2CH3
That's the benzyl ethyl ether.
When this compound reacts with a concentrated Solution of HI, as we have an acid medium, we will have an SN1 reaction, where the Hydrogen will attach to the oxygen and the iodine will go to the most stable carbon, in this case, the carbon next to the ring is the most stable (because of the double bond of the ring, charges can be stabilized better this way), so product A will be the benzyl with the iodine and product B, will be the alcohol:
A: Ph - CH2 - I
B: CH3CH2OH
When B reacts again with HI, it's promoting another SN1 reaction, where the OH substract the H from the HI, the OH2+ will go out the molecule, leaving a secondary carbocation (CH2+) and then, the Iodine (I-) can go there via SN1 and the final product would be:
C: CH3CH2I
See picture for mechanism:
Final answer:
The student's question pertains to the reaction of benzyl ethyl ether with concentrated aqueous HI, following an SN1 mechanism. The reaction generates a halogenated product (A) and an alcohol (B), with the alcohol further reacting to form a reduction product (C). Specific structures cannot be provided without more information on the starting compound.
Explanation:
The student is inquiring about the reaction of benzyl ethyl ether with concentrated aqueous HI and the subsequent products. The reaction is characteristic of the SN1 mechanism of ether cleavage, particularly with ethers that have benzylic, allylic, or tertiary alkyl groups. In such reactions, the benzyl or allylic group forms a relatively stable carbocation, leading to the formation of a halogen product (product A), while the ether's other alkyl substituent becomes an alcohol (product B).
Further reaction of product B with HI would lead to the formation of product C, which is typically the reduction of the alcohol to an alkane or a similar process depending on the specific structure of product B. Without the detailed structure of benzyl ethyl ether, we cannot provide the exact structures of the final products A, B, and C.
Predict the reactants of this chemical reaction. That is, fill in the left side of the chemical equation. Note: you are writing the molecular, and not the net ionic equation.
→ CaCl2(aq) + H20(l)
Answer:
Ca(OH)₂ and HCl(aq)
Explanation:
We have the products of a reaction, CaCl₂ and H₂O. Since the products are a salt and water, this is likely to be a neutralization reaction. In such a reaction, an acid and a base react to form a salt and water.
The acid provides the anion of the salt. Since the anion is Cl⁻, the acid is HCl(aq).The base provides the cation of the salt. Since the cation is Ca²⁺, the base is Ca(OH)₂(aq).The complete molecular equation is:
Ca(OH)₂ + 2 HCl(aq) → CaCl₂ + 2 H₂O