Questions
Please answer all three thank you! Part A To what volume should you dilute 155 mL...

Please answer all three thank you!

Part A

To what volume should you dilute 155 mL of an 8.60 M CuCl2 solution so that 60.0 mL of the diluted solution contains 5.9 g CuCl2? Answer in mL

Part B

What is the molarity of an aqueous solution that is 5.69 % NaCl by mass? (Assume a density of 1.02 g/mL for the solution.)

Part C

Ocean water contains 3.5 % NaCl by mass. How much salt can be obtained from 304 g of seawater? Express your answer using two significant figures.

In: Chemistry

In a study, 2-MeV neutrons enter a target made of water and are gradually absorbed in...

In a study, 2-MeV neutrons enter a target made of water and are gradually absorbed in the water.

Assume:

1. The neutrons don't interact with oxygen

2. Their capture cross section before they thermalize is 2.5 barns.

Calculate (for the neutrons):

a. Mean free path.

b. Linear momentum as they the target.

c. Velocity as they enter the target.

d. Calculate the neutron's lifetime in the medium (average time before they are captured).

Indicate all units.

In: Chemistry

A 0.9000 g sample of a mixture of NaCl and KCl is dissolved in water, and...

A 0.9000 g sample of a mixture of NaCl and KCl is dissolved in water, and the solution is then treated with an excess of AgNO3 to yield 1.923 g of AgCl. Calculate the percent by mass of each compound in the mixture.

____% mass of NaCl

____% mass of KCl

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why the compound to be crystallized should be very soluble in the hot solveng and less...

why the compound to be crystallized should be very soluble in the hot solveng and less soluble in the cold solvent ??
and why impure solid dissolves in the minimum volume of hot solvent ? why minimum ??

In: Chemistry

a) Calculate the change in entropy on heating an ideal gas from 300K to 500K at...

a) Calculate the change in entropy on heating an ideal gas from 300K to 500K at constant pressure.

b) Calculate the change in entropy on heating an ideal gas from 300K to 500K at constant volume.

c) why these answers are different.

Please explain each steps.

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What additives may be used to prevent acid catalyzed hydrolysis of drugs containing ester moieties in...

What additives may be used to prevent acid catalyzed hydrolysis of drugs containing ester moieties in drug formulations?

In: Chemistry

Please answer: Discuss how many anions are able to contaminate groundwater.

Please answer:
Discuss how many anions are able to contaminate groundwater.

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Menthol is a crystalline substance with a peppermint taste and odor. When 1.19 g of menthol...

Menthol is a crystalline substance with a peppermint taste and odor. When 1.19 g of menthol is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is lowered by 6.34 ∘ C. Look up the freezing point and K f constant for cyclohexane in the Colligative Constants table. Calculate the molar mass of menthol.

Solvent Formula Kf value*

(°C/m)

Normal freezing

point (°C)

Kb value

(°C/m)

Normal boiling

point (°C)

water H2O 1.86 0.00 0.512 100.00
benzene C6H6 5.12 5.49 2.53 80.1
cyclohexane C6H12 20.8 6.59 2.92 80.7
ethanol C2H6O 1.99 –117.3 1.22 78.4
carbon
tetrachloride
CCl4 29.8 –22.9 5.03 76.8
camphor C10H16O 37.8 176

In: Chemistry

Imagine two solutions with the same concentration and the same boiling point, but one has ethanol...

Imagine two solutions with the same concentration and the same boiling point, but one has ethanol as the solvent and the other has carbon tetrachloride as the solvent. Determine that molal concentration, m (or b),m (or b), and boiling point, Tb.Tb.

Solvent Normal boiling point (∘C)(∘C) Kb (∘C/m)Kb (∘C/m)
ethanol 78.4 1.22
carbon tetrachloride 76.8 5.03

m=

Tb=

In: Chemistry

Firefly luciferase is the enzyme that allows fireflies to illuminate their abdomens. Because this light generation...

Firefly luciferase is the enzyme that allows fireflies to illuminate their abdomens. Because this light generation is an ATP-requiring reaction, firefly luciferase can be used to test for the presence of ATP. In this way, luciferase can test for the presence of life. The coupled reactions are

1.2.luciferin+O2ATP⇌⇌oxyluciferin+lightAMP+PPiΔG∘=−31.6 kJ/mol

If the overall ΔG∘ of the coupled reaction is -5.50 kJ/mol , what is the equilibrium constant, K, of the first reaction at 23 ∘C ?

In: Chemistry

This is a physical chemistry question. Write down for yourself the secular determinant for the hypothetical...

This is a physical chemistry question.

Write down for yourself the secular determinant for the hypothetical molecule linear H3 making the Huckel approximation, using the 1s atomic orbitals from each atom as the basis set. Given that α=-2.00 eV and β= -2 eV, what is the total electronic energy in eV?

In: Chemistry

(I already have part A but still still include it anyways so you can use its...

(I already have part A but still still include it anyways so you can use its data to solve for parts B and C.

Chemical energy is released or absorbed from reactions in various forms. The most easily measurable form of energy comes in the form of heat, or enthalpy. The enthalpy of a reaction can be calculated from the heats of formation of the substances involved in the reaction:

ΔH∘rxn=ΔH∘f(products)−ΔH∘f(reactants)

Entropy change, ΔS∘, is a measure of the number of energetically equivalent microstates introduced into the system during the reaction. The degree of spontaneity of a reaction is represented by the Gibbs free energy, ΔG∘. The Gibbs free energy depends on both the enthalpy and entropy changes that take place during the reaction:

ΔG∘=ΔH∘−TΔS∘

where T is standard temperature, 298 K.

Part A

Part complete

Calculate the standard enthalpy change for the reaction

2A+B⇌2C+2D

where the heats of formation are given in the following table:

Substance ΔH∘f
(kJ/mol)
A -261
B -425
C 175
D -491

Express your answer in kilojoules.

ΔH∘rxn = 315 kJ  

Part B

For the reaction given in Part A, how much heat is absorbed when 3.30 mol of A reacts?

Express your answer numerically in kilojoules.

Part C

For the reaction given in Part A, ΔS∘rxn is 41.0 J/K . What is the standard Gibbs free energy of the reaction, ΔG∘rxn?

Express your answer numerically in kilojoules.

In: Chemistry

According to the ideal gas law, a 9.776 mol sample of xenon gas in a 0.8177...

According to the ideal gas law, a 9.776 mol sample of xenon gas in a 0.8177 L container at 499.7 K should exert a pressure of 490.2 atm. By what percent does the pressure calculated using the van der Waals' equation differ from the ideal pressure? For Xe gas, a = 4.194 L2atm/mol2 and b = 5.105×10-2 L/mol.

In: Chemistry

Which of the following types of solids typically contain electronegative atoms? Select all that apply. Select...

Which of the following types of solids typically contain electronegative atoms?

Select all that apply.
Select all that apply:
metallic
ionic
covalent network
molecular

In: Chemistry

Concentration of HCl can be measured by its reaction with Na2CO3: 2H+ + Na2CO3 –> 2Na+...

Concentration of HCl can be measured by its reaction with Na2CO3: 2H+ + Na2CO3 –> 2Na+ + H2O + CO2 A volume of 23.75 ± 0.04 mL HCL solution was required to completely react with 0.9674 ± 0.0009 g of Na2CO3. Given that FM of sodium carbonate is 105.988 ± 0.001 g. Find the molarity of HCl and its absolute uncertainty.

In: Chemistry