Atomic structure and bonding - Jamb Chemistry Past Questions and Answers

Question 46:

• JAMB 1989

The atomic number of caesium is 55 and its atomic mass is 133. The nucleus of caesium atom therefore contains

A. 78 protons and 55 elections
B. 55 protons and 78 neutrons
C. 55 neutrons 78 electrons
D. 78 protons and 55 neutrons

Question 47:

• JAMB 1989

Four elements P,Q, R and S have atomic numbers of 4, 10, 12 and 14 respectively . Which of these electrons is a noble gas?

A. P
B. Q
C. R
D. S

Question 48:

• JAMB 1989

How many valence electrons are contained in the element represented ³¹₁₅P?

A. 3
B. 5
C. 15
D. 31

Question 49:

• JAMB 1990

.....................P....Q.....R......S
Proton..............13....16....17.....19
Electron............13....16....17.....19
Neutron.............14....16....35.....20
Which of the four atoms P,q,R and in S in the above data can be described by the following properties relative atomic mass is greater than 30 but less than 40; it has an odd atomic number and forms a unipositive ion in solution?

A. P
B. Q
C. R
D. S

Question 50:

• JAMB 1990

Which of the following terms indicates the number of bonds that can be formed by an atom?

A. Oxidation number
B. Valence
C. Atomic number
D. Electronegativity