what is the name of NiI2

Answer:

What are the statements please

Explanation:

Answer: Here are the statements

Explanation:

A.

One that has 30.0 grams NaCl dissolved in 100 grams of water is more concentrated than one that has 15.0 grams NaCl dissolved in 100 grams of water.

B.

One that has 30.0 grams NaCl dissolved in 100 grams of water is more dilute than one that has 15.0 grams NaCl dissolved in 100 grams of water.

C.

One that has 30.0 grams NaCl dissolved in 100 grams of water would have the exact same molarity as one that has 15.0 grams NaCl dissolved in 100 grams of water.

D.

One that has 30.0 grams NaCl dissolved in 100 grams of water has less solute than one that has 15.0 grams NaCl dissolved in 100 grams of water.

Answer: Physical change

Explanation: Condensation is the phase change of a gas to the liquid state. There is no formation of new products so it does not undergoes chemical change. Any phase change is considered a physical change.

Final answer:

Condensation of ethanol is a physical change because it only involves a change in the state of matter without altering the chemical composition of ethanol.

Explanation:

The condensation of ethanol is a physical change. This process involves a change in the state of matter from gas to liquid without altering the chemical composition of ethanol. Like the condensation of water vapor into liquid water, the process is exothermic, releasing energy. However, the ethanol remains chemically identical before and after condensation.

Answer: Temperature final = 103 °C

Explanation: To solve for final temperature we use the equation of heat:

Q= mc∆T

Next derive the equation to find final temperature

Q = mc(T final - T initial)

Q / mc = T final - T initial

Transpose T initial and change the sign so that T final will be left.

T final = Q / mc + T initial

Substitute the values:

T final = 305 J / 28.8 g x 0.128 J/(g°C)

= 305 J / 3.6864 J/°C

= 82.7 + 20.0°C

= 103 °C final temperature.

Answer:

8.8 cm³

Explanation:

Data given:

volume of Liquid = 0.0088 L

convert volume to Cubic centimeters

Solution:

There are number of unit in which volume can be measured

As

Liter is unit of volume represented by L

Cubic centimeters represented by cm³

liter is larger value then cm³

Now to convert L to cm³

As we Know

1 L = 1000 cm³

So

Apply unity formula

           1 L = 1000 cm³

           0.0088 L = x cm³

Do Cross multiplication

            x cm³ = 0.0088 L x 1000 cm³ /  1 L

            x cm³ = 8.8 L.cm³ /  1 L

            x cm³ = 8.8 cm³

So,

0.0088 L of liquid = 8.8 cm³

Final answer:

To convert 0.0088 liters to cubic centimeters, multiply by the conversion factor of 1,000. This yields a volume of 8.8 cubic centimeters.

Explanation:

In a fluid, the particles are still in close contact, so fluids have an unmistakable volume. In any case, in light of the fact that the particles can move about one another fairly openly, a fluid has no positive shape and takes a shape directed by its compartment.

To convert the volume of a liquid from liters to cubic centimeters, we can use the conversion factor that 1 liter is equivalent to 1,000 cubic centimeters (cm³). Since 1 milliliter (mL) is also equivalent to 1 cubic centimeter (cm³), we first convert liters to milliliters before converting to cubic centimeters.

The volume given is 0.0088 L. To convert this to milliliters, we multiply by the conversion factor:

0.0088 L × 1,000 mL/1 L = 8.8 mL

Now, since 1 mL is equal to 1 cm³, the volume in cubic centimeters is:

8.8 cm³

Explanation:

When two or more substances react and form some new substance it is called as chemical reaction .

A + B --> C + D

(reactants )   (products )

Types of chemical reaction

we come across different types of reactions that occur in nature .

Out of them , combination is also one type

Combination reaction

It is a reaction ,when two or more reactants react to form single product .

i.e A+B-----AB(IN THIS ONE SINGLE PRODUCT IS FORMED )

LIKE : H₂+Cl₂------HCL

         (E)    (E)         (PRODUCT )

           SO₂+O₂----SO₃

             ©   (E)        (PRODUCT )

           CO₂+H₂O----H₂CO₃

In the above asked equation :

C₂H₂ + 2 H₂ --> C₂H₆

Final answer:

The reaction C2H2 + 2H2 → C2H6 represents a hydrogenation reaction, converting acetylene to ethane by adding hydrogen. This process, central to organic chemistry, often requires a catalyst and is foundational in the synthesis of various compounds.

Explanation:

The given reaction C2H2 + 2H2 → C2H6 is an example of a hydrogenation reaction, where hydrogen (H2) is added to another compound. In this specific case, the hydrogenation of acetylene (C2H2) results in ethane (C2H6). The process involves the breaking of the triple bond in acetylene and the formation of a single bond to incorporate the additional hydrogen atoms, converting it into ethane. This is a common type of chemical reaction in organic chemistry which often requires a catalyst such as platinum or palladium to proceed under milder conditions.

The importance of understanding reactions like these lies in their application in the synthesis of various organic compounds, which are foundational in fields ranging from pharmaceuticals to materials science. Stoichiometry, a crucial concept in such reactions, involves the calculation of reactant and product quantities, often expressed in moles, to ensure that a reaction proceeds efficiently and yields the desired product.

I pretty sure its C. Work

If wrong lemme know

Explanation:

we can find number of atoms in a given sample by the formula :

Number of atoms = Given mass /atomic mass  x Avogadro's number

or , it can be written as :

Number of atoms = given mass /atomic mass x 6.022 x 10²³

Now in above asked question , the values given are :

Mass of sample of gold = 72.04g

Atomic mass of gold : 196.6

Avogadro's number = 6.023 x 10²³

so, using the above formula we have :

Number of atoms = 72.04 /196.6 x 6.022 x 10²³

= 0.3664 x 6.022 x 10²³

=2.207 x 10²³ number of atoms

Answer:

NON-Renewable source of energy takes millions of years to renew whereas renewable renews in short duration of time.

Explanation:

Renewable resource are the resources which can be renewed in short duration of the time and can be used again and again without any threat of exhaustion whereas the Non-renewable resource cannot be renewed in short duration of time and takes millions of the years to renew and are made naturally in specific environment.

Some examples of the Non-renewable resources are coal, Petroleum, natural gas, fossil fuels etc.

Also Renewable energy includes Solar energy, Hydro energy, wind energy etc.

Non Renewable energy is limited to a certain time period of several years and will get exhausted after some time because of this we should shift to renewable source of the energy and conserve them for our future generations.

Answer: C. Suspension

Explanation: Suspensions are mixtures where its solute particles are not fully dissolved in a solvent. The size of its particles are much relatively the biggest among other mixtures such as solutions and colloids. Since its has bigger particle size it suspends and settle at the bottom of the container due to gravity. So when using suspensions it is advised to shake it well before using to mix the suspended particles.

A medicine that needs to be shaken well before use is considered a Suspension. This is a type of mixture where small solid particles are dispersed in a liquid and will settle if the mixture is not stirred.

A medicine that must be shaken well before use is typically a Suspension. A suspension is a type of mixture where small solid particles are dispersed throughout a liquid but are not dissolved in the liquid. A characteristic feature of suspensions is that the particles will eventually settle at the bottom of the mixture and are allowed to stand undisturbed, hence the instruction 'shake well before using'.

A solution, on the other hand, is a mixture where the solute is fully dissolved in the solvent, and it does not need to be stirred before use. An alloy is a solid mixture of two or more metals, and a colloid is a mixture where very small particles of one substance are dispersed evenly throughout another substance.

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Answer: 18g/mol

Explanation:

H2O = (2 x 1) +16 = 2 + 16 = 18g/mol

Answer: 107.87 g/mol

Explanation: I just took the test

Answer:

107.87 g/mol

Explanation:

Answer:

1 fempto = 10⁻¹⁵

Explanation:

Data Given:

9.2 fempto second = 9.2 ×10 ⁻¹⁵ seconds

exponential equivalent of fempto = ?

Solution:

To find exponential equivalent of fempto

As we know

we look at the given data

That is fempto seconds = 9.2

when we write only seconds then we write 10⁻¹⁵ instead of fempto

that is

9.2 ×10 ⁻¹⁵ seconds

So the exponential equivalent of fempto = 10 ⁻¹⁵

That is -15 exponent to 10

So,

10 ⁻¹⁵ = 0.00000000000001

1 fempto = 10 ⁻¹⁵

Answer: 1000 g of water at 30°C

Explanation: Heat or thermal energy is directly proportional to the mass of an object, which implies that the more massive the object the greater thermal energy or heat it can absorb. Since the amount of matter present is much more enough to absorb heat energy.

Answer:

86.04 %

Explanation:

Data given:

mass of Al  = 160.0 g

actual yield Al₂O₃= 260 g

Theoretical yield = ?

percent yield ofAl₂O₃ = ?

Solution:

First we have to find theoretical yield.

So,

we Look at the balanced reaction

             4Al  + 3O₂ -----—> 2Al₂O₃

             4 mol                      2 mol

As 4 mole of Al give 2 mole of Al₂O₃

Convert moles to mass

molar mass of Al = 27 g/mol

molar mass of Al₂O₃ = 2(27) + 3(16)

molar mass of Al₂O₃ = 54 + 48

molar mass of Al₂O₃ = 102 g/mol

Now

             4Al         +       3O₂   -----—>     2Al₂O₃

        4 mol (27g/mol)                       2 mol (102 g/mol)

             108 g                                            204 g

108 grams of Al produce 204 g of Al₂O₃

So

if 108 grams of Al produce 204 g of Al₂O₃ so how many grams of Al₂O₃ will be produced by 160 g of Al.

Apply Unity Formula

              108 grams of Al  ≅ 204 g of Al₂O₃

              160 grams of Al ≅ X of Al₂O₃

Do cross multiply

              mass of Al₂O₃= 204 g x 160 g / 108 g

              mass of Al₂O₃ = 302.2 g

So the Theoretical yield of Al₂O₃ = 302.2 g

Now Find the percent yield of Al₂O₃

Formula Used

             percent yield = actual yield /theoretical yield x 100 %

Put value in the above formula

            percent yield = 260g / 302.2 g x 100 %

            percent yield = 86.04 %

percent yield of Al₂O₃ = 86.04 %

Final answer:

The theoretical yield is 302.3 grams of Al2O3, and the percent yield is 86.0%, found by comparing the actual yield of 260.0 grams to the theoretical yield.

Explanation:

The question asks us to calculate the theoretical yield and percent yield when burning aluminum (Al) to produce aluminum oxide (Al2O3). The mass of Al used is 160.0 grams, and the amount of Al2O3 produced is 260.0 grams.

To calculate the theoretical yield, we first need to use the stoichiometry of the balanced reaction:
4Al(s) + 3O2(g) → 2Al2O3(s).

Next, convert the given mass of Al to moles using its molar mass (27.0 g/mol):
(160.0 g Al) / (27.0 g/mol Al) = 5.93 moles Al

According to the stoichiometry, 4 moles of Al produce 2 moles of Al2O3, so:
(5.93 moles Al) x (2 moles Al2O3 / 4 moles Al) = 2.965 moles Al2O3

Then convert moles of Al2O3 to grams using its molar mass (101.96 g/mol):
(2.965 moles Al2O3) x (101.96 g/mol Al2O3) = 302.3 grams Al2O3

This is the theoretical yield. The percent yield is calculated as follows:
(Actual Yield / Theoretical Yield) x 100
(260.0 g / 302.3 g) x 100 = 86.0%

The chemist achieved an 86.0% percent yield.

The answer is a change in internal energy causes work to be done and heat to flow into the system.  

Explanation:

Answer:

i believe that the answer is a

Explanation:

Two things that must be in circuits to make them work are a conductor and a voltage source.

Explanation:

There are tow main parts that helps all electric circuits to work. They are a conductor and a voltage source. Some of the other parts of circuits includes,switches and bulbs. The working of an electrical circuit is same as that of the human circulatory system. The blood is taken to all parts of human body with the help of the blood vessels in a circulatory system.

Same thing happens with an electrical circuit. This is responsible in taking current to all parts of an electrical system. In an electrical circuit electricity will flow from the voltage of high to low. A path should be there for conducting the electric power.

Answer:

1.27 moles (3 s.f.)

Explanation:

Mole ratio of water: C6H14

= 14:2

= 7:1

This means that to produce 7 moles of water, 1 mole of C6H14 is needed. Or 1/7 mole of C6H14 is needed to produce 1 mole of water. So if you need 8.86 moles of water, 8.86(1/7) moles of C6H14 is needed.

For 8.86mol of water, moles of C6H14 needed

= 8.86/7

= 1.27 moles (3 s.f.)

Answer:

a. 0 J

b. - 9.5J

c. - 17.8 J

Explanation:

part a  (against a vacumm)

Data given:

initial volume V1 = 26.7 mL

Final volume V2 = 89.3 mL

work done w = ?

temperature = constant

Solution:

formula will be used

             w = - PΔV

where

ΔV = V2 -V1

so the above equation will be written as

          w = - P (V2 - V1) . . . . . . (1)

as we are calculating work against vacuum so the pressure will be 0 atm.

So,

P = 0 atm

Put values in above equation 1

              w = - [(0 atm)(89.3 mL - 26.7 mL)

              w = - [(0 atm)(62.6mL)

               w = - (0)J

               w = 0 J

so the work done will be 0

_________________

part b (against constant pressure of 1.5)

Data given:

initial volume V1 = 26.7 mL

Convert mL to L

1000 mL = 1 L

26.7 mL = 26.7/1000 = 0.0267 L

Final volume V2 = 89.3 mL

Convert mL to L

1000 mL = 1 L

89.3 mL = 89.3/1000 = 0.0893 L

work done w = ?

Pressure constant = 1.5 atm

Solution:

formula will be used

             w = - PΔV

where

ΔV = V2 -V1

so the above equation will be written as

          w = - P (V2 - V1) . . . . . . (1)

Put values in above equation 1

              w = - [(1.5 atm)(0.0893 L - 0.0267 L)

              w = - [(1.5 atm)(0.0626 L)

               w = - (0.0939 atm.L)

               w = - 0.0939 atm.L

convert atm.L to J

1 atm.L = 101.3 J

0.0939 atm.L = 0.0939 x 101.3 = 9.5 J

so the work done will be - 9.5 J

___________

Part c ( constant pressure of 2.8 atm)

Data given:

initial volume V1 = 26.7 mL

Convert mL to L

1000 mL = 1 L

26.7 mL = 26.7/1000 = 0.0267 L

Final volume V2 = 89.3 mL

Convert mL to L

1000 mL = 1 L

89.3 mL = 89.3/1000 = 0.0893 L

work done w = ?

Pressure constant = 2.8 atm

Solution:

formula will be used

             w = - PΔV

where

ΔV = V2 -V1

so the above equation will be written as

          w = - P (V2 - V1) . . . . . . (1)

Put values in above equation 1

              w = - [(2.8 atm)(0.0893 L - 0.0267 L)

              w = - [(2.8 atm)(0.0626 L)

               w = - (0.1753 atm.L)

               w = - 0.1753 atm.L

convert atm.L to J

1 atm.L = 101.3 J

0.1753 atm.L = 0.1753 x 101.3 = 17.8 J

so the work done will be - 17.8 J

Final answer:

Chemistry high school question about the work done by an expanding gas against different pressures. The work done against a vacuum is 0 J, against 1.5 atm is -9.49 J (approx.), and against 2.8 atm is -17.71 J (approx.). Calculations use the formula W=-P_ext×ΔV and the conversion 1 L·atm = 101.32 J.

Explanation:

The subject of this question is Chemistry, specifically the topic of thermodynamics as it relates to gases. In the scenario provided, a gas is expanding and the work done by the expansion needs to be calculated in different contexts:

(a) against a vacuum

(b) against a constant pressure of 1.5 atm

(c) against a constant pressure of 2.8 atm

To calculate the work (W) when a gas expands or contracts against an external pressure (Pext), the formula W=-Pext×ΔV is used, where ΔV is the change in volume. However, when a gas expands against a vacuum, the external pressure is zero, so the work done is zero as well.

To calculate the work done against a constant pressure in joules, we first need to find the change in volume (ΔV) in liters and the pressure in atmospheres. Then we use the relationship 1 L·atm = 101.32 J to convert from L·atm to joules.

ΔV = 89.3 mL - 26.7 mL = 62.6 mL = 0.0626 L

Work done against a vacuum (Wvacuum) = 0 J

Work done against 1.5 atm (W1.5) = -1.5 atm × 0.0626 L × 101.32 J/L·atm = -9.4878 J

Work done against 2.8 atm (W2.8) = -2.8 atm × 0.0626 L × 101.32 J/L·atm = -17.7062 J

Note that the work is negative because work is done by the system (expansion of gas) against the surroundings.

A chemical change happened when the two substances were mixed together in the flask. It wasn't a physical shift because that involves transforming a pure substance's state into a solid, liquid, or gas.

Chemical synthesis, or, alternatively, chemical breakdown into two or more separate molecules, occurs when one material reacts with another to create a new substance. These processes are referred to as chemical reactions, and they are typically irreversible barring additional chemical reactions.

Chemical modifications are those in which a new substance with new chemical characteristics is created. Examples include the CO2 and other chemical reactions that occur when lemon juice and washing soda are combined.

A chemical change is characterized by a shift in temperature. To check for a temperature change during an experiment, one could dip a thermometer into a beaker or an Erlenmeyer flask. It is likely that a chemical change is taking place if the temperature rises, which it does in the majority of reactions.

Thus, A chemical change happened when the two substances were mixed together in the flask.

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Final answer:

A chemical change occurred when two chemicals were combined based on the formation of new substance (white flakes), temperature change indicating an exothermic reaction, and the production of gas (bubbles).

Explanation:

Based on the given information, a chemical change occurred when the two chemicals were combined. The evidence for a chemical change rather than a physical change is as follows:

Physical changes, such as the melting and boiling of pure substances, involve changes in state but do not result in the formation of a new substance or significant temperature changes as observed here.

Answer:Density

Explanation:

Answer:density

Explanation:

Answer: The 3 indicates the 3rd shell

Explanation:

Answer:

Salt is ionic, and oil is covalent. If you add water, the salt will dissolve in the water, and the oil will float to the top. You could then skim the oil and start over with sugar. To double-check, you could even make sure the oil does not conduct electricity!

Explanation:

just took on edge 2020

Removing salt from oil is difficult and complex, requiring particular separation processes. In most domestic situations, it's more feasible to discard the oil and start fresh.

When you accidentally add salt to the oil instead of sugar, it becomes a bit problematic to remove it. This is because both oil and salt are not miscible with water and the salt has likely dissolved into the oil. Removing the salt would need a separation process, such as centrifuge separation or sequential filtration. Unfortunately, these methods are complex and usually not readily available in a typical domestic environment.

As a simple solution, it might be more feasible to discard the salted oil and start fresh. This would save time and ensure that no unwanted salty flavor is incorporated into your food preparation.

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Answer:

B

Explanation:

since heat was produced...its an exothermic reaction

we don't have a proof for conclude this is a combustion..also we dont have enough information to identify products...

Therefore My only conclusion is B

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Answer:

Explanation:

1 : False

A divergent plate boundary is when two plates pull apart.

2: A

I explained what a divergent boundary was in the previous question

3 : B

Think of the word converge/come together

4: D

When two continental plates collide, they form a mountain

When a continental, and oceanic plate collide, the oceanic plate sub-ducts, and melts. That causes a volcano. The volcano becomes a mountain to some extent.

5 : C

When the plates divert, magma spews from the mid ocean ridge.

6 : Divergent

7 : Transform plate boundaries move in opposite directions

8 : B

When the plates grind together, energy is stored, and then is suddenly released

9 : True

10 : True

11 : C

This is a set of questions and answers related to plate boundaries including divergent, convergent and transform boundaries. The Himalayan mountain range is a result of convergent plate boundaries, while new seafloors are created at divergent boundaries. Transform plate boundaries, which move in opposite or lateral directions, often yield earthquakes.

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Answer:

Yes, the unknown substance is the liquid ethylene glycol.

Explanation:

Here the density of the unknown substance is 69.22lb/f and the density of ethylene glycol, the liquid used in antifreeze is 1.1088g/ml

We know, 1g  = 0.0022lb

1ml= [tex]3.531 \times 10^{-5} ft^3[/tex]

Therefore, 1g/ml = 62.428[tex]lb/ft^3[/tex]

Since, the density of ethylene glycol = 1.1088g/ml

 = 1.1088 [tex]\times[/tex] 62.428 [tex]lb/ft^3[/tex]

= 69.22 [tex]lb/ft^3[/tex]

When the density of ethylene gas is converted from g/ml unit to [tex]lb/ft^3[/tex] unit, it is found to have the same value (69.22)Therefore, the unknown substance here is liquid ethylene glycol.

Explanation:

that is the answer for your question

Scientists discovered Earth's outer core is liquid because shear waves from earthquakes do not pass through it, while compression waves do. Inge Lehmann interpreted seismic data to confirm this structure. The core's heat is maintained by the radioactive decay of elements.

The question relates to how scientists discovered that Earth's outer core is liquid. Inge Lehmann played a pivotal role in interpreting seismological data from earthquakes. It was observed that shear waves, which cannot travel through liquid, do not transmit through the Earth's core, unlike compression waves, which do. This was key evidence indicating that the outer core was liquid.

Since shear or transverse waves are not transmitted through the Earth's outer core, but longitudinal waves pass through, it indicated differing properties consistent with a liquid outer core and a solid inner core. The Earth's core was found to consist of a liquid outer core surrounding a solid inner core, made of materials like iron and nickel. The composition and presence of these elements also led to the creation of Earth's magnetic field.

The substantial heat of the Earth's interior, despite the expectation of cooling over 4.5 billion years, is maintained by the radioactive decay of primordial elements. The density of the mantle rock increases with depth and occasionally is studied when ejected from volcanoes, bearing detailed chemistry for analysis.

The average kinetic energy of the particles is directly proportional to the

C) Kelvin temperature

Explanation:

The average kinetic energy of the particles in a substance is given by the equation:

[tex]KE=\frac{3}{2}kT[/tex]

where

KE is the average kinetic energy

[tex]k=1.38\cdot 10^{-23} J/k[/tex] is a constant, called Boltzmann constant

T is the absolute temperature of the substance, in Kelvin

From the equation, we see that the average kinetic energy of the particles is directly proportional to the

C) Kelvin temperature

This is because the Kelvin temperature gives a measure of the amount of motion of the particles in a medium: indeed, at absolute zero (= temperature of zero Kelvin), the particles in a substance have ideally no kinetic energy, and therefore T = 0).

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Answer: A. 190 lbs.

Explanation: To find the mass in pounds we will use the following conversion factor: 1 lb = 0.45 kg

Solution:

87 kg x 1 lb / 0.45kg = 193 lbs.

Among the choices 190 lbs is the closest so it is the answer.

Assuming that the complete question is the following:

Calcium hydroxide reacts with Aluminum sulfate to form aluminum hydroxide and calcium sulfate. Write the balanced formula unit equation for the reaction.

Then the balanced formula unit equation would be:

3Ca(OH)₂ + Al₂(SO₄)₃ → 2Al(OH)₃ + 3CaSO₄

This is a double replacement reaction, where the cations and anions are interchanged.

Balancing this reaction is based on the Law of Conservation of Mass, which estates that matter is not created nor destroyed, meaning that the number of atoms at the right and the left of the chemical equation needs to be the same. We add coefficients in front of each species that intervenes in the reaction in order to achieve that equality.

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The question is about the chemical reaction between calcium hydroxide and aluminum sulfate, where aluminum hydroxide precipitates and calcium sulfate remains in solution. The aluminum hydroxide can be filtered out and then converted into aluminum oxide for electrolysis to produce metallic aluminum.

The student asks about the reaction between calcium hydroxide and aluminum sulfate. In a chemical reaction, calcium hydroxide, represented as Ca(OH)2, would react with aluminum sulfate, which is Al2(SO4)3 to form a precipitate of aluminum hydroxide (Al(OH)3) and a solution of calcium sulfate (CaSO4).

For such a reaction, the balanced chemical equation can be written as:

During this process, aluminum hydroxide precipitates from the solution, which can then be removed by filtration. Further treatment, such as heating, can convert the aluminum hydroxide to aluminum oxide (Al2O3), commonly used in the electrolysis process for aluminum production. This process involves dissolving aluminum oxide in a molten mixture of cryolite and calcium fluoride, followed by the application of an electric current to reduce aluminum ions to metallic aluminum at the cathode.