ATOMIC STRUCTURE & CHEMICAL BONDING IX

An atom with 3 protons and 4 neutrons will have a valency of

• 3

• 4

• 7

• 1

The only inert gas which have a complete duplet is

• Krypton

• neon

• Argon

• Helium

Number of valence electron in O^2- are:

• 6

• 8

• 4

• 10

The valency of which of the following element is zero ?

• helium

• Hydrogen

• Nitrogen

• Zinc

The property which is characteristic of an electrovalent compound is that

• it is easily vaporized

• it has high melting point

• it often exists as a liquid

• it is a weak electrolyte

When a metal atom becomes an ion

• it loses electrons & is oxidized

• it gains electron & is reduced

• it loses electrons & is reduced

• it gains electron & is oxidized

An atom has the mass number 35 & the atomic number is 17. The number of neutron in its nucleus are

• 17

• 35

• 18

• 52

isotopes have different mass number,because their nuclei contain different number of

• proton

• electron

• neutron

• positron

The chemical bond formed between mutual sharing of electrons between the two combining atom

• Ionic bond

• dative bond

• electrovalent bond

• covalent bond

The number of electrons lost or gained by an atom refers to

• Donation

• acceptance

• covalency

• electrovalency