Jamb Chemistry 2020 Past Questions and Answers

Question 36:

• JAMB 2020

When a solid substance disappears completely as a gas on heating, the substance is said to have undergone?

A. Sublimation
B. Crystallization
C. Distillation
D. Evaporation

Question 37:

• JAMB 2020

An electron can be added to a halogen atom to form a halide ion with?

A. 8 valence electrons
B. 7 valence electrons
C. 2 valence electrons
D. 3 valence electrons

Question 38:

• JAMB 2020

Aluminum hydroxide is used in the dyeing industry as a?

A. Dye
B. Dispersant
C. Salt
D. Mordant

Question 39:

• JAMB 2020

The most important element on the earth's crust is?

A. Nitrogen
B. Hydrogen
C. Oxygen
D. Fluorine

Question 40:

• JAMB 2020

To obtain pure carbon(ii)oxide from its mixture with carbon(iv)oxide, the mixture should be?

A. Passed over heated copper(ii)oxide
B. Bubbled through water
C. Bubbled through conc H\(_2\)SO\(_4\)
D. Bubbled through conc NAOH