Question 561:

• JAMB 1988

The forces holding naphthalene crystals together can be overcome when naphthalene is heated to a temperature of 354K resulting in the crystal to melting. These forces are known as?

A. Coulombic
B. Ionic
C. Covalent
D. Van der waals

Question 562:

• JAMB 1988

A metallic ion X²⁺ with an inert gas structure contains 18 electrons. How many protons are there in this ion?

A. 20
B. 18
C. 16
D. 2

Question 563:

• JAMB 1988

Which of the following physical properties decreases across the Periodic Table?

A. Ionization potenial
B. Electron affinity
C. Electronegativity
D. Atomic radius

Question 564:

• JAMB 1988

What are the possible oxidation numbers of an element if its atomic number is 17?

A. -1 and 7
B. -1 and 6
C. -3 and 5
D. -2 and 6

Question 565:

• JAMB 1988

The energy changes accompanying the addition of an electron to a gaseous atom is called?

A. First ionization energy
B. Second ionization energy
C. Electron affinity
D. Electronegativity