Jamb Chemistry 2015 Past Questions and Answers

Question 51:

• JAMB 2015

Electronic configuration of an elements 13x in the subsidiary energy level is

A. \( 1s^2 2s^2 2p^6 3s^2 3p^1 \)
B. \( 1s^22s^2 2p^4 3p^1 3s^1 \)
C. \( 1s^2 2s^2 2p^6 3s^2 3p^3 \)
D. \( 1s^1 2s^2 2p^6 3s^2 3p^4 \)

Question 52:

• JAMB 2015

Alloys are best prepared by

A. Electroplating
B. Arc-welding
C. Reducing and mixture of their metallic
D. Cooking a molten of the metals

Question 53:

• JAMB 2015

In countries where the temperature fall below 273k, salt always spilled on the ray road in order to

A. Increase the making point office
B. Increase the density of the ice
C. Make the ice impure
D. Rinse the making point of the ice

Question 54:

• JAMB 2015

What is the volume of energy required to burn 45cm\(^3\) of mixture at S.T.P

A. 135.0cm³
B. 150.0cm³
C. 45.0cm³
D. 90.0cm³

Question 55:

• JAMB 2015

The substance that is used in the steel industry for the removal of carbon. Sulphur and phosphorus impurities from pig iron is

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