JAMB Chemistry Past Questions & Answers - Page 340

1,696.

Which quantum number divides shells into orbitals?

A.

Principal

B.

Arzimuthal

C.

Magnetic

D.

Spin

Correct answer is B

The principal quantum number, n, describes the energy of an electron and the most probable distance of the electron from the nucleus.

In other words, it refers to the size of the orbital and the energy level an electron is placed in.

The azimuthal quantum number is a quantum number for an atomic orbital that determines its orbital angular momentum and describes the shape of the orbital.

1,697.

Cathode rays causes an object placed behind a perforated anode to cast a shadow on the screen. This observation shows that the rays?

A.

are positively charged

B.

are negatively charged

C.

have mass

D.

travel in straight lines

Correct answer is D

Cathode rays travel in a straight line and can cast sharp shadows.

Cathode rays are negatively charged.

Electric field and magnetic field deflect cathode rays.

1,698.

If an atom is represented as \( _{11}^{23}X \), which of the following deduction is correct?

A.

it contains 12 protons

B.

it forms a covalent chloride

C.

its atomic number is 23

D.

it is an alkali metal

Correct answer is D

Sodium has atomic / proton number of 11 and belongs to Group 1[alkali metals] on the periodic table

1,699.

The basic assumption in the kinetic theory of gases that the collisions of the gaseous molecules are perfectly elastic implies that the?

A.

forces of attraction and repulsion are in equilibrium

B.

gaseous molecules can occupy any available space

C.

gaseous molecules will continue their motion indefinitely

D.

gases can be compressed

Correct answer is C

An elastic collision is an encounter between two bodies in which the total kinetic energy of the two bodies remains the same.

1,700.

A gas exerts pressure on its container because?

A.

the molecules of a gas collide with the walls of the container

B.

some of the molecules are moving faster than others

C.

of the collisions of the molecules with each other

D.

of the mass of the molecules of the gas

Correct answer is A

Gas pressure is the name given to the force exerted by gas particles colliding with the wall of their container.