Answer:
2.07 grams
Explanation:
We know that the molecular mass of [tex]K_2CO_3[/tex] is 138.205 grams.
In order to find out how many grams we need to make 200 mL having a potassium ion concentration of 0.150, we need to find the number of moles first.
M = moles / liters
0.150 = x / 0.200
x = 0.03 moles
Since there are 2 potassium atoms in each molecule of [tex]K_2CO_3[/tex] so we will divide this number by half and multiply it by the molecular mass.
0.03/2 = 0.015 moles
Mass of [tex]K_2CO_3[/tex] needed = 0.015 × 138.205 = 2.07 grams
To prepare 200.0 mL of a solution with a potassium ion concentration of 0.150 M, it requires D) 2.07 g of K₂CO₃.
To determine the mass of K₂CO₃ needed to prepare 200.0 mL of a solution with a potassium ion concentration of 0.150 M, follow these steps:
Determine the number of moles of potassium ions required using the concentration formula:
C = n / VWhere C is the concentration (0.150 M), n is the number of moles, and V is the volume in liters (0.200 L):
0.150 M = n / 0.200 LSolve for n (number of moles of K⁺):
n = 0.150 M * 0.200 L = 0.030 moles of K⁺K₂CO₃ contains two potassium ions per formula unit, so divide the moles of K⁺ by 2 to find the moles of K₂CO₃:
0.030 moles / 2 = 0.015 moles of K₂CO₃Find the molar mass of K₂CO₃:
Atomic mass of K = 39.1 g/molAtomic mass of C = 12.0 g/molAtomic mass of O = 16.0 g/molMolar mass of K₂CO₃ = 2(39.1 g/mol) + 12.0 g/mol + 3(16.0 g/mol) = 138.2 g/molCalculate the mass of K₂CO₃ needed:
Mass = moles * molar mass = 0.015 moles * 138.2 g/mol = 2.073 gThus, you need 2.073 g of K₂CO₃ to prepare 200.0 mL of a solution with a potassium ion concentration of 0.150 M.
Correct question is: What mass of K₂CO₃ is needed to prepare 200. mL of a solution having a potassium ion concentration of 0.150 M?
A) 4.15 g
B) 10.4 g
C) 13.8 g
D) 2.07 g
E) 1.49 g
if the initial concentration of acetic acid is .200 M and the equilibrium concentration of H3O+ is .0019 M, calculate Ka for acetic acid
The acid dissociation constant (Ka) for acetic acid, given the initial concentration of 0.200 M and the equilibrium concentration of H3O+ is 0.0019 M, is 1.82 × 10⁻µ.
Explanation:To calculate the acid dissociation constant (Ka) for acetic acid, we can use the information provided that the initial concentration of acetic acid is 0.200 M and the equilibrium concentration of H3O+ is 0.0019 M. Using the chemical equation for the dissociation of acetic acid (CH3COOH):
CH3COOH(aq) ⇌ CH3COO−(aq) + H3O+(aq),
we know that at equilibrium, the concentration of H3O+ ions will be the same as the concentration of CH3COO− ions. Therefore, [CH3COO−] = [H3O+] = 0.0019 M.
Because acetic acid is a weak acid, we can assume that the change in concentration of acetic acid is roughly equal to the concentration of H3O+ ions produced. Thus, the equilibrium concentration of CH3COOH will be 0.200 M - 0.0019 M = 0.1981 M. The formula for Ka is:
Ka = [CH3COO−][H3O+] / [CH3COOH]
Substituting the equilibrium concentrations into this formula gives:
Ka = (0.0019 M)(0.0019 M) / (0.1981 M) = 1.82 × 10⁻µ,
which is the Ka for acetic acid.
Which chemical element has the shortest name?
Answer:
deez nuttts
Explanation:
Element 50
Symbol Sn
TIN
A drum Can begin to vibrate at its natural frequency without being struck through:
A. Refection
B.diffraction
C.refraction
D. Resonance
Answer IS D!!
Answer:
[tex]\boxed{\text{D. Resonance}}[/tex]
Explanation:
If an external vibration matches the drum's natural frequency, it will induce the can to vibrate. This is an example of resonance.
It is analogous to pumping your legs in synchronization with a swing's natural frequency.
Which is a sustainable practice? A. Wind farms B. Clear cutting C. Flood irrigation D. Overfishing
When a practice is sustainable, it means that it can be used over and over through time. Sustainable practices also benefit, rather than harm, the environment. Though it really depends on where you live, the general answer for this would be wind farms since flood irrigation can only happen in certain conditions. Overfishing would destroy a species over time, and clear cutting is obviously harmful to the environment.
The sustainable practice can be described as one that can be seen in A. Wind farms . option A is correct.
What is sustainable practice?It has the capacity to be maintained, upheld, or affirmed. Science of the environment. the property of not being environmentally destructive or depleting natural resources, promoting long-term ecological balance: The committee is creating sustainability criteria for energy-using products.
Sustainable practices promote the health and vitality of the environment, people, and the economy. According to sustainability, resources are limited and should be used prudently with an eye toward long-term goals and the effects of how they are used.
Hence , option A is correct.
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Which rule is used for writing the name of an ionic base?
The chemical name begins with “hydro.”
The chemical name ends with “hydroxide.”
The “ide” ending is changed to “ic.”
The polyatomic “ate” ending is changed to “ic.”
Answer:
The chemical name ends with “hydroxide.”
Explanation:
1- we write the name of the metal first and after that write the nonmetal:
Ex : NaOH ( sodium hydroxide)
2- any compound contains OH group is an ionic base and this group called hydroxide group
3- "Ous" ending is given in the ions with the lower oxidation.
4- " ic" ending is given in the ions with the higher oxidation.
So, the correct answer is: The chemical name ends with “hydroxide.”.
Answer:
The chemical name ends with “hydroxide
Explanation:
got right on edge 2020
The bond between F and Cl would be: pure covalent polar covalent ionic metallic
Answer:
Polar Covalent
Explanation:
Chlorine and Fluorine are both halogens. They are in group VII.
The Pauling's electronegativity value of these elements are:
F = 4.0
Cl = 3.0
Electronegativity of an element is a property that combines the ability of its atom to lose and gain electrons. It can be used to predict bond type.
For heteronuclear molecules where the electronegativity difference is between 0.5 and 1.7 there will not be an equal sharing of the electron pair between the atoms involved.
The bond that results is a Polar Covalent bond.
When the electronegativity difference is zero or less than 0.5, a non-polar covalent bond forms. There would be an equal sharing of the electron pair donated.
Which human activity will most likely contribute to ozone layer destruction?
Final answer:
The use of aerosol sprays and coolants that release chlorine and bromine gases contributes to ozone layer destruction, leading to increased UV radiation and environmental harm. The Montreal Protocol helped reduce emissions of ozone-depleting substances, slowing the rate of depletion.
Explanation:
The human activity that most likely contributes to ozone layer destruction is the release of chlorine and bromine gases through the use of products like aerosol sprays and coolants. These substances are known as ozone-depleting substances (ODS), and include chemicals such as chlorofluorocarbons (CFCs).
When these substances reach the stratosphere, they release halogen radicals that catalytically destroy ozone molecules, leading to ozone depletion. This has severe environmental and health impacts, such as increased UV radiation leading to higher rates of skin cancers and disrupted ecosystems. The Montreal Protocol was a successful international effort to phase out the production and use of ODS, which has led to a decrease in the rate of ozone depletion, but vigilance and continued reduction of emissions are essential to protect the ozone layer.
What are two fungal skin infections that humans can contract?
pneumonia and ergot disease
ergot disease and athlete’s foot
athlete’s foot and ringworm
ringworm and pneumonia
Answer:
athlete’s foot and ringworm- third choice
The two common fungal skin infections that humans can contract are athlete's foot and ringworm. They are both caused by fungi called dermatophytes, treated with antifungal creams and powders, and more persistent cases may require prescription medication.
The two common fungal skin infections that humans can contract are athlete's foot and ringworm.
Athlete's foot, medically known as tinea pedis, is a contagious infection that affects the skin on the feet and can spread to the toenails and sometimes the hands.
It is characterized by a scaly rash that usually causes itching, stinging, and burning.
Ringworm, or tinea corporis, is not caused by a worm but by a fungus, and it presents as a red, circular rash on the skin.
Both of these infections are caused by dermatophytes, which are fungi that feed on keratin, a protein found in skin, hair, and nails.
These infections are typically treated with over-the-counter antifungal creams and powders, although more persistent cases might require prescription medication.
A chemist prepares an aqueous solution with a volume of 250 mL, containing 4.3 g of KOH. what is the molarity of the solution?
Answer:
either 58.1 or 1075
Explanation:
250 / 4.3 = 58.1
250 * 4.3
How is acid rain produced ?
Answer:
acid rain is produced from harmful emissions in the air clinging to the water molecules and coming down as rain
Explanation:
The type of acid rain that contains water is called wet deposition. Acid rain formed with dust or gasses is called dry deposition.
Need help on this ASAP !!!!
Answer:
2:2
Explanation:
The question is on mole ration in a chemical equation.
Steps to identify mole ratio in an equation
Write a balance chemical equation-atoms of elements in the reactant side should equal that of the product side2H₂ + O₂⇒ 2H₂O------------------This equation is balanced. how?
Number of hydrogen atoms in reacting side= 2×2=4
Number of hydrogen atoms in the products side= 2×2=4
Number of oxygen atoms in the reacting side=2
Number of oxygen atoms in the product side =2
Writing the mole ratio in the equation
2H₂ + O₂⇒ 2H₂O
2 1 2
Mole ratio of hydrogen to water
2H₂ + O₂⇒ 2H₂O
2 2
= 2:2
where is the DNA prokaryote?
A. nucleotides
B. nucleoid region
C. Nucleoid center
Answer:
Prokaryotes have no cell nucleus and no membrane enclosed organelles. Prokaryotic DNA can be found in a coiled loop floating in the cytoplasm in a region called the nucleoid (meaning nucleus-like). In other words, the nucleoid is the area in a prokaryotic cell where DNA is located.
Explanation:
The DNA in prokaryotes is found in the nucleoid region, which is the central part of the cell where their single, circular chromosome is located along with concentrated DNA-associated proteins and plasmids. So the correct option is B.
Explanation:The DNA in a prokaryote is located in a central part of the cell known as the nucleoid region. Prokaryotes, which include Bacteria and Archaea, have a single, circular chromosome that is not bound by a complex nuclear membrane. This chromosome is found within the nucleoid region, and this area does not readily stain, making it appear lighter in color when viewed with a transmission electron microscope. Additionally, the prokaryotic DNA and DNA-associated proteins are concentrated within this region. Prokaryotes often possess plasmids as well, which are shorter, circular DNA molecules that can carry traits such as antibiotic resistance and can be transferred independently during cell division.
HELP ASAP! GIVING BRAINLIEST!!
Think about the process of raising a pendulum to one side and letting it go. For this event, create a list associated with the pendulum as it cycles from the choices below:
KINETIC ENERGY FORMS:
- Motion energy
- Thermal energy
- Electric energy
- Vibrational energy
- Radiant energy
POTENTIAL ENERGY FORMS:
- Gravitational Potential energy
- Elastic Potential energy
- Chemical Potential energy
- Electric Potential energy
- Magnetic Potential Energy
- Nuclear Potential energy
Answer:
impossible
Explanation:
Answer:
Kinetic energy
Potential energy
Motion energy
Which of the following elements would most likely have the physical property of malleability?
A. N
B. He
C. Cu
D. P
A. N would probably be the one
100 ml of gaseous hydrocarbon consumes 300
ml of oxygen for the complete combustion.
The hydrocarbon is
a. C2H4
b. C2H2
C. C3H8
d. C2H6
The answer would be a. C2H4(ethylene)
1C2H4+3O2~>2CO2+2H2O
Answer:
a. C2H4.
Explanation:
Let's look at the balanced equation for C2H4.
C2H4 + 3O2 --> 2CO2 + 2H2O
So 1 mole of this hydrocarbon reacts with 3 moles of oxygen and since 1 mole of one gas occupies the same volume as another gas, the volumes will be in the ratio 1:3. So this is the required hydrocarbon.
What is the change in atomic mass when an atom emits a beta particle? Please explain your answer
no significant change
decreases by 2
decreases by 1
increases by 1
no significant change
Explanation:
When an atom emits a beta particle, a neutron is changed into a proton by emitting an electron. The electron has a negligible mass (very small), hence there is no significant change in atomic mass.
What happens to the molarity of a salt solution if the number of moles of salt in the solution is multiplied by three and the number of liters of the solution is also multiplied by three? The molarity of the solution remains unchanged. The molarity of the solution becomes three times as much. The molarity of the solution becomes six times as much. The molarity of the solution decreases.
Answer:
The molarity of the solution remains unchanged.
Explanation:
Consider the formula for the molarity [tex]M[/tex] of a solution:
[tex]\displaystyle M = \frac{n}{V}[/tex],
where
[tex]n[/tex] is the number of moles of solute in this solution, and[tex]V[/tex] is the volume of the solution.For this salt solution,
[tex]n_{1} = 3\;n_{0}[/tex], and[tex]V_{1} = 3\;V_{0}[/tex].Initial molarity:
[tex]\displaystyle M_{0} = \frac{n_{0}}{V_{0}}[/tex].
Final molarity:
[tex]\displaystyle M_{1} = \frac{n_{1}}{V_{1}} = \frac{3\;n_{0}}{3\;V_{0}} = \frac{n_{0}}{V_{0}} = M_{0}[/tex].
In other words, the molarity of the solution remains unchanged.
Answer:
The molarity of the solution remains unchanged
Explanation:
Thulium-167 has a half life of 9.0 days. If the initial amount of thulium is 50.0 grams. How many grams are left after 36.0 days?
Answer:
3.125 grams.
Explanation:
It is known that the decay of a radioactive isotope isotope obeys first order kinetics.Half-life time is the time needed for the reactants to be in its half concentration.If reactant has initial concentration [A₀], after half-life time its concentration will be ([A₀]/2).Also, it is clear that in first order decay the half-life time is independent of the initial concentration.∵ Thulium-167 has a half life of 9.0 days.
∴ The time is needed to calculate the grams are left after (36.0 days) represents (36.0 days / 9.0 days) = 4.0 half-lives.
50.0 grams → (first half life) 25.0 grams → (second half life) 12.5 grams → (third half life) 6.25 grams → (fourth half life) 3.125 grams.
So, the grams are left after 36.0 days = 3.125 grams.
Need Help ASAP- Chemistry
Answer:
Q1: 1.67 L.
Q2: Saturated solution.
Explanation:
Q1:
We have the role that the no. of millimoles before dilution is equal to the no. of millimoles after dilution.(MV) before dilution = (MV) after dilution
M before dilution = 10.0 M, V before dilution = 0.5 L.
M after dilution = 3.0 M, V after dilution = ??? L.
∴ V after dilution = (MV) before dilution / M after dilution = (10.0 M)(0.5 L) / (3.0 M) = 1.67 L.
Q2:
From the given curve, it is clear that the solubility of sodium nitrate at 35.0°C is 100 g per 100 g of water.
So, the mentioned solution is a saturated solution at this T.
A saturated solution is a chemical solution containing the maximum concentration of a solute dissolved in the solvent.
What is an organic chemical?
Answer:
Organic chemistry is a subdiscipline of chemistry that studies the structure, properties and reactions of organic compounds, which contain carbon in covalent bonding. Study of structure determines their chemical composition and formula.
Consider the chemical equations shown here.
2Na(s) + Cl2(g) → 2NaCl(s)
4Na(s) + O2(g) → 2Na2O(s)
What is the overall equation for the reaction that produces NaCl and O2 from Na2O and Cl2?
Na2O(s) + Cl2(g) --> NaCl(s) + O2(g)
2Na2O(s) + Cl2(g)--> 2NaCl(s) + O2(g)
2Na2O(s) + 2Cl2(g)--> 4NaCl(s) + O2(g)
Answer:
2Na₂O₍s₎+ 2Cl₂₍g₎⇒4 NaCl₍s₎ +O₂₍g₎
Explanation:
The more reactive chlorine gas displaces the less reactive oxygen gas from the compound sodium oxide. The correct equation is C. because the number of each type atom on each side is equal hence the equation is balanced. There are 4 sodium atoms on the left side as there are on the right, 4 chlorine on both sides and two oxygen on both sides.
Answer : The correct equation will be,
[tex]2Na_2O(s)+2Cl_2(g)\rightarrow 4NaCl(s)+O_2(g)[/tex]
Explanation :
The given reactions are:
(1) [tex]2Na(s)+Cl_2(g)\rightarrow 2NaCl(s)[/tex]
(2) [tex]4Na(s)+O_2(g)\rightarrow 2Na_2O(s)[/tex]
Both the given chemical reactions are balanced chemical reaction. So, in order to get the final equation we first multiply equation 1 by 2 and reverse the equation 2 then add both the equations, we get the overall equation for the reaction the produces [tex]NaCl[/tex] and [tex]O_2[/tex] from [tex]Na_2O[/tex] and [tex]Cl_2[/tex]
(1) [tex]4Na(s)+2Cl_2(g)\rightarrow 4NaCl(s)[/tex]
(2) [tex]2Na_2O(s)\rightarrow 4Na(s)+O_2(g)[/tex]
The final reaction will be,
[tex]2Na_2O(s)+2Cl_2(g)\rightarrow 4NaCl(s)+O_2(g)[/tex]
what is mascara made out of?
Answer: most contain the same basic components of pigments, oils, waxes, and preservatives.
Explanation: YOOOO was up :))))))
A solution is prepared by dissolving 106.3 g HCl(g) in enough water to make 175.0 L of solution. The ph of this solution is
The pH of the solution resulting from the dissolution of 106.3 g HCl in 175.0 L of water is 1.77.
The pH of a solution is given by:
[tex] pH = -log([H_{3}O^{+}]) [/tex] (1)
Since HCl is a strong acid, we have that:
[tex] [H_{3}O^{+}] = [HCl] [/tex]
We can calculate the concentration of HCl from its mass and the volume of solution:
[tex] [HCl] = \frac{106.3 g}{175.0 L}*\frac{1 mol}{36.46 g} = 0.017 g/mol [/tex]
Hence, the pH is (eq 1):
[tex] pH = -log([H_{3}O^{+}]) = -log(0.017) = 1.77 [/tex]
Therefore, the pH of the solution is 1.77.
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Iron and aluminum are examples of _____________.
Iron and aluminum are examples of elements, which are pure substances that cannot be broken down into simpler substances by chemical changes. Both are naturally occurring and widely used in various applications.
Explanation:Iron and aluminum are examples of elements. Elements are pure substances that cannot be broken down into simpler substances by chemical changes. Iron and aluminum both occur naturally on earth and are widely used in various applications. For example, iron is a key component in steel making and is also an important element in hemoglobin in the blood, while aluminum is a good reducing agent and is used in a multitude of products such as foil and cookware. Other examples of elements include silver, gold, sulfur, oxygen, and copper.
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A balloon was partially filled with helium gas at room temperature. It occupied 4.0 liters of volume at 700.0 mmHg atmospheric pressure. When the balloon was released, it traveled upward until it burst at 99 mmHg atmospheric pressure. (Neglect any force exerted to stretch the rubber balloon.) What was the volume of the balloon when it burst? L
Answer:
28.28 L.
Explanation:
We can use the general law of ideal gas: PV = nRT.where, P is the pressure of the gas in atm.
V is the volume of the gas in L.
n is the no. of moles of the gas in mol.
R is the general gas constant,
T is the temperature of the gas in K.
If n and T are constant, and have two different values of V and P:P₁V₁ = P₂V₂
P₁ = 700.0 mm Hg, V₁ = 4.0 L.
at burst: P₂ = 99.0 mm Hg, V₂ = ??? L.
∴ V₂ = P₁V₁/P₂ = (700.0 mm Hg)(4.0 L)/(99.0 mm Hg) = 28.28 L.
What mass of ammonium chloride is dissolved in 300 mL of a 0.875M solution?
Answer:
9.32 g.
Explanation:
Molarity is the no. of moles of solute per 1.0 L of the solution.M = (no. of moles of NH₄Cl)/(Volume of the solution (L))
M = 0.875 M.
no. of moles of NH₄Cl = ??? mol,
Volume of the solution = 300 mL = 0.3 L.
∴ (0.875 M) = (no. of moles of NH₄Cl)/(0.3 L)
∴ (no. of moles of NH₄Cl) = (0.875 M)*(0.3 L) = 0.2625 mol.
To find the mass of NH₄Cl, we can use the relation:no. of moles of NH₄Cl = mass/molar mass
∴ mass of NH₄Cl = (no. of moles of NH₄Cl)*(molar mass) = (0.2625 mol)*(53.491 g/mol) = 9.316 g ≅ 9.32 g.
The mass of ammonium chloride dissolved in 300 mL of a 0.875M solution is 14.90 g.
Explanation:To find the mass of ammonium chloride dissolved in 300 mL of a 0.875M solution, we need to use the formula:
Mass = Volume x Concentration x Molar mass
The molar mass of ammonium chloride is 53.49 g/mol. Substituting the given values, we get:
Mass = 0.300 L x 0.875 mol/L x 53.49 g/mol = 14.90 g
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How do scientist know climate change is happening is it
A.They measure the amount of greenhouse gases in the atmosphere, and the temperature over many years
B.They measure the amount of water in the ocean that covers the earth
C.They measure the amount of clouds in the atmosphere over many years.
Answer: The answer would be A;They measure the amount of greenhouse gases in the atmosphere, and the temperature over many years.
Explanation: If scientists only went off of clouds, they'd only be able to tell if it is about to rain. If they only observed the oceans, they'd only be able to tell when a tornado or tsunami was about to occur.
Answer: The answer is A. Thay measure the amount of greenhous gases in the atmosphere and the temperature over many years
Explanation:
For a phase change, H = -44 kJ/mol and SO = -0.12 kJ/(K•mol). What are
G and the spontaneity of the phase change at 350 K?
Answer:
ΔG = - 2.0 kJ/mol and the reaction is spontaneous.
Explanation:
∵ ΔG = ΔH - TΔS,
ΔH = - 44.0 kJ/mol, T = 350.0 K, ΔS = - 0.12 kJ/K.mol.
∴ ΔG = ΔH - TΔS = (- 44.0 kJ/mol) - (350.0 K)(- 0.12 kJ/K.mol) = - 2.0 kJ/mol.
The sign of ΔG assigns the spontaneity of the reaction:
If ΔG is negative: the reaction is spontaneous.If ΔG = 0, the reaction is at equilibrium.If ΔG is positive: the reaction is non-spontaneous.∵ ΔG has a negative value, so the reaction is spontaneous.
So, the answer is:
ΔG = - 2.0 kJ/mol and the reaction is spontaneous.
The specific heat of a certain type of cooking oil is 1.75 J/(g⋅°C). How much heat energy is needed to raise the temperature of 2.94 kg of this oil from 23 °C to 191 °C?
Answer:
[tex]\boxed{\text{864 kJ}}[/tex]
Explanation:
The formula for the heat transferred to or from an object is
q = mCΔT
Data:
m = 2.94 kg
C = 1.75 J·°C⁻¹g⁻¹
T₁ = 23 °C
T₂ = 191 °C
Calculations:
(a) Convert the mass to grams
m = 2.94 kg = 2940 g
(b) Calculate ΔT
ΔT = T₂ - T₁ = 191 – 23 = 168 °C
(c) Calculate q
q = 2940 × 1.75 × 168 = 864 000 J = 864 kJ
You must provide[tex]\boxed{\textbf{864 kJ}}[/tex].
A crystal of graphite contains which type of bond?
Answer:
Graphite has a giant covalent structure in which:
each carbon atom is joined to three other carbon atoms by covalent bonds
the carbon atoms form layers with a hexagonal arrangement of atoms
the layers have weak forces between them
each carbon atom has one non-bonded outer electron, which becomes delocalised:
A crystal of graphite contains a covalent structure.
What is an example of a covalent bond structure?This is an example of a substance with a huge covalent bond structure. It contains a lot of silicon and oxygen atoms. All atoms in the structure are linked to each other by strong covalent bonds. Atoms combine in a regular arrangement to form a huge concurrent structure.
A giant covalent bond structure is a three-dimensional structure of atoms bonded by covalent bonds. Allotropes are different forms of the same element in the same state. Graphite, graphene, and diamond are allotropes of the same element (carbon) in the same state (solid). Carbon can form up to 4 covalent bonds
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