NET Applied Sciences MCQs

A cation forms when electrons are lost.
It has more protons than electrons.

An anion forms when electrons are gained.
It has more electrons than protons.

Rutherford concluded that atoms contain a small dense positive nucleus.
Most atomic volume is empty space.

Thomson's cathode-ray experiments revealed negatively charged particles.
He proposed an early model with electrons in positive matter.

Chadwick identified the neutral nuclear particle in 1932.
Neutrons explain isotopic mass differences.

Quantum mechanics describes electron probability distributions.
An orbital can hold up to two electrons with opposite spins.

The Pauli exclusion principle allows two electrons per orbital.
They must have opposite spin quantum numbers.

An s subshell contains one orbital.
It can hold a maximum of two electrons.

A p subshell contains three orbitals.
It can hold a maximum of six electrons.

Atomic number identifies the element.
In a neutral atom it also equals the number of electrons.

Mass number applies to a specific isotope.
It is always a whole number.

Isotopes have the same atomic number but different mass numbers.
Their chemical behavior is usually similar.