Air - Jamb Chemistry Past Questions and Answers

Question 21:

• JAMB 1999

A pair of compounds that can be used to generate a gas which has physiological effect on human beings is

A. Sodium trioxonitrate (V) and calcium chloride
B. Sodium dioxonitrate (III) and ammonium chloride
C. Sodium trioxonitrate (V) and ammonium chloride
D. Sodium dioxonitrate (III) and potassium chloride

Question 22:

• JAMB 2000

The noble gas, argon,is used for

A. Electric arc welding
B. Welding brass
C. Underwater welding
D. Steel welding

Question 23:

• JAMB 2001

Deliquescent substance are used for

A. Cooling
B. Wetting
C. Melting
D. Drying

Question 24:

• JAMB 2001

What is the decrease in volume of air when pyrogallol is shaken with 30.00cm³ of air ?

A. 15.00cm³
B. 6.30cm³
C. 0.63cm³
D. 0.06cm³

Question 25:

• JAMB 2002

Steam changes the colour of anhydrous cobalt (II) chloride from

A. Blue to pink
B. White to red
C. White to green
D. Blue to white