The periodic table and periodicity of elements - Jamb Chemistry Past Questions and Answers

Question 21:

• JAMB 1989

Elements X and Y have electronic configurations 1s²2s²2p⁶ and 1s²2s²2p⁶3s²3p¹ respectively. When they combine, the formula of the compound formed is

A. XY
B. YX
C. X₂Y₃
D. Y₂X₃

Question 22:

• JAMB 1991

Which of the following is arranged in order of increasing electronegativity?

A. Chlorine, aluminium, magnesium, phosphorus, sodium
B. Sodium, magnesium, aluminium, phosphorus, chlorine
C. Chlorine, phosphorus, phosphorous, aluminium, magnesium, sodium
D. Sodium, chlorine, phosphorus, magnesium, aluminium

Question 23:

• JAMB 1994

Which of the following is the correct order of decreasing activity of the metals Fe, Ca, Al and Na?

A. Fe> Ca> Al> Na
B. Na> Ca> Al> Fe
C. Al> Fe> Na> Ca
D. Ca> Na> Fe>, Al

Question 24:

• JAMB 1995

Group 1 A metals are not found free in nature because they?

A. Are of low melting and boiling points
B. Have weak metallic bonding
C. Conduct electricity and heat
D. Are very reactive

Question 25:

• JAMB 1995

USE THE SECTION OF THE PERIODIC TABLE ABOVE TO ANSWER THIS QUESTION.Which of the indicate an alkali metal and a noble gas respectively?

A. M and E
B. G and E
C. R and L
D. G and L