Thermodynamics of Mixing

Thermodynamics of Mixing

Multiple Choice

What is the formula for the Gibbs Free Energy change?

• ΔG= ΔH – TS

• ΔG=ΔH – ΔTS

• ΔG=TΔS – ΔH

• ΔG= ΔH – TΔS

Multiple Choice

What is the percent composition of a sugar solution where 10 grams of sugar is added to 100 grams of water?

• .10%

• 0.091%

• 9.090909%

• 9.1%

Multiple Choice

What is the molarity of 4 grams of sodium chloride (NaCl) in 3,800 mL of solution?

• 0.018 M
• 0.018 m
• 1.052 M
• 1.052 m

Multiple Select

What are the two forms of concentration used most in chemistry?

• Percent by mass

• Percent by volume

• Molarity

• Molality

Multiple Choice

How does the entropy of a solution compare to the entropy of a pure solvent?

• Increased

• Decreased

• Same

Open Ended

Why is the entropy of a solution greater than the entropy of a pure solvent?

Multiple Choice

A non-electrolyte is composed of __________in solution

• molecules

• molecules and ions

• ions

• none of the above

Open Ended

How are chemical potential and molar Gibbs free energy related?

Multiple Choice

Which of the following statements is always true for a liquid mixture of two components A and B in equilibrium with a mixture of their vapours?

• mA(l) = mB(l) and mA(g) = mB(g)

• mA(l) = mA(g) = mB(l) = mB(g) incorrect

• mA(l) = mA(g) and mB(l) = mB(g)

• mA(l) ≠ mA(g) ≠ mB(l) ≠ mB(g) incorrect

Open Ended

How do we know the mixing of gases is spontaneous?

Open Ended

In a gaseous mixture there is no change in enthalpy. Would there be a change in enthalpy in a liquid solution? Why?

Multiple Choice

Calculate the entropy change when 2.0 mol of a perfect gas A and 3.0 mol of a perfect gas B mix spontaneously.

• 195 J/K

• 28 J/K

• -12 J/K

• -8.34 J/K

Poll

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