Jamb Chemistry 2019 Past Questions and Answers

Question 126:

• JAMB 2019

Methane is prepared in the laboratory by heating a mixture of sodium ethanoate with soda lime. The chemical constituent(s) of soda lime is/are

A. Ca(OH)\(_2\) and NaOH
B. Na\(_2\)CO\(_3\)
C. NaCl
D. NaOH

Question 127:

• JAMB 2019

Which of the following sets of operation will completely separate a mixture of sodium chloride, sand and iodine?

A. Addition of water, filtration, evaporation to dryness and sublimation
B. Filtration, evaporation to dryness, addition of water and sublimation
C. Sublimation, filtration, evaporation and addition of water
D. Sublimation, addition of water, filtration and evaporation to dryness

Question 128:

• JAMB 2019

200cm\(^3\) of 0.50mol/dm\(^3\) solution of calcium hydrogen trioxocarbonate (IV) is heated. The maximum weight of solid precipitated is

A. 10g
B. 25g
C. 20g
D. 15g

Question 129:

• 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 130:

• JAMB 2019

X is a substance which liberates CO\(_2\) on treatment with concentrated H\(_2\)SO\(_4\). A warm solution of X can decolorize acidified KMnO\(_4\). X is

A. HCOOH
B. NaHCO\(_3\)
C. FeCO\(_3\)
D. H\(_2\)C\(_2\)O\(_4\)