FIRST TERM CLASS 9 CHEMISTRY

The scientist known as the Father of Electricity is

• Sir Humphry Dav

• Ernest Rutherford

• John Dalton

• Michael Faraday

An atom is electrically neutral because of the presence of equal number of

• Protons and neutrons

• Protons and electrons

• Electrons and neutrons

• All of these

The mass number of an element is the number of

• Electrons and neutrons

• Protons

• Protons and electrons

• Protons and neutrons

The atomic number of an element is 17 and its mass number is 35,

• it has 18 protons

• has 17 neutrons

• has 18 neutrons

• has 18 electrons

The isotope used as a fuel in atomic reactors is

• Cobalt-60

• Iodine-131

• Carbon-14

• Uranium-235

Which of the following electronic configurations is a stable structure?

• 2, 8, 6

• 2, 8, 8

• 2, 8, 7

• 2. 7

The chemical bonding formed by the sharing of electrons is

• Ionic bonding

• Covalent bonding

• Co-ordinate bonding

• Metallic bonding

Which of the following is not a property of ionic bonding?

• Found only in the solid state.

• Conducts electricity in molten and aqueous states

• Soluble in organic solvents

• High melting and boiling points

The type of chemical bond in a nitrogen molecule is

• Ionic bond

• Triple covalent bond

• Double covalent bond

• Single covalent bond

Which of the following is a polar molecule?

• HCl

• N₂

• H₂

• NaCl