In 1911 Ernest Rutherford used experimental evidence to show that an atom must contain a central nucleus. Niels Bohr further developed Rutherford’s nuclear atom model. He used experimental evidence to support the idea that electrons occupy particular orbits or shells around the nucleus of an atom.

Correct Option: A

In 1911 Ernest Rutherford used experimental evidence to show that an atom must contain a central nucleus. Niels Bohr further developed Rutherford’s nuclear atom model. He used experimental evidence to support the idea that electrons occupy particular orbits or shells around the nucleus of an atom.

The calorific value of Gasoline is 47,300 kJ/kg. The calorific value of a fuel is the quantity of heat produced by its combustion - at constant pressure and under “normal” conditions (i.e. to 0oC and under a pressure of 1,013 mbar).

Correct Option: D

The calorific value of Gasoline is 47,300 kJ/kg. The calorific value of a fuel is the quantity of heat produced by its combustion - at constant pressure and under “normal” conditions (i.e. to 0oC and under a pressure of 1,013 mbar).

Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.

Correct Option: B

Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.

A mole of a gas is the amount of a substance containing 6.023 x 10²³ atoms. This is known as Avogadro’s number. 1 mole contains the same number of particles as there are in 12 g of carbon-12 atoms by definition. 12 g of carbon-12 atoms = 6.022 x 10²³carbon atoms.

Correct Option: B

A mole of a gas is the amount of a substance containing 6.023 x 10²³ atoms. This is known as Avogadro’s number. 1 mole contains the same number of particles as there are in 12 g of carbon-12 atoms by definition. 12 g of carbon-12 atoms = 6.022 x 10²³carbon atoms.

Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass-produced since 1893 for use as an abrasive.

Correct Option: A

Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass-produced since 1893 for use as an abrasive.