Energy changes - Jamb Chemistry Past Questions and Answers

Question 86:

• JAMB 2018

The situation obtained when a perfect gas expands into a vacuum is

A. ΔH is positive and TΔ S is zero
B. ΔH is positive and T Δ S is negative
C. ΔH is negative and TΔ S is zero
D. ΔH is zero and T Δ S is positive

Question 87:

• JAMB 2019

Which of the following conditions will most enhance the spontaneity of a reaction?

A. \(\Delta\)H is negative and greater than T\(\Delta\)S
B. \(\Delta\)H is negative and \(\Delta\)S = 0
C. \(\Delta\)H is positive and less than T\(\Delta\)S
D. \(\Delta\)H is positive and equal to T\(\Delta\)S

Question 88:

• JAMB 2019

The part of the total energy of a system that accounts for the useful work done in a system is known as

A. Enthalpy change
B. None of the above
C. Gibb's free energy
D. Entropy

Question 89:

• JAMB 2020

An example of a polysaccharide is?

A. Dextrose
B. Mannose
C. Glucose
D. Starch

Question 90:

• JAMB 2020

32g of anhydrous copper(ii)tetraoxosulphate(vi) dissolved in 1dm\(^3\) of water generated 13.0kj of heat. The heat solution is?

A. 26.0kj/mol
B. 65.0kj/mol
C. 130.0kj/mol
D. 260.0kj/mol