Jamb Chemistry 1999 Past Questions and Answers

Question 6:

• JAMB 1999

Which of the following will have its mass increased when heated in air?

A. Helium
B. Magnesium
C. Copper pyrites
D. Glass

Question 7:

• JAMB 1999

Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
From the equation above, the mass of magnesium required to react with 250cm3 of 0.5M HCl is
[Mg = 24]

A. 0.3g
B. 1.5g
C. 2.4g
D. 3.0g

Question 8:

• JAMB 1999

A gaseous metallic chloride MCl_x consists of 20.22% of M by mass. The formula of the chloride is
[M = 27, Cl = 35.5]

A. MCl
B. MCl₂
C. MCl₃
D. M₂Cl₆

Question 9:

• JAMB 1999

In which of the following are water molecules in the most disorderly arrangement?

A. Ice at -10°C
B. Ice at 0°C
C. Water at 100°C
D. Steam at 100°C

Question 10:

• JAMB 1999

In order to remove one electron from a 3S orbital of gaseous sodium atom, about 496KJMol^-1 of energy is required. This energy is referred to as

A. Electron affinity
B. Ionization energy
C. Activation evergy
D. Electronegativity