Atoms MCQs with Answers

One-liner

The maximum number of electrons in the third orbit (n=3) is 18, as given by the formula 2n².

One-liner

The proton was discovered by Ernest Rutherford in 1919 through his gold foil alpha particle scattering experiment.

One-liner

The 6p orbital has more energy than 4s, 5d, and 3d because orbital energy increases with the principal quantum number (n) and, for the same n, follows the order s < p < d < f.

One-liner

Protons and electrons have charges that are equal in size but opposite in sign — protons are positive and electrons are negative.

One-liner

Canal rays are positively charged radiations discovered by Eugen Goldstein in a discharge tube experiment.

One-liner

The 4f orbital is more energetic because, according to the (n+l) rule, 4f has a higher n+l value (4+3=7) compared to 3d (3+2=5), 3p (3+1=4), and 4s (4+0=4).

One-liner

As the atomic number increases in a group, the chemical properties stay roughly the same because elements in the same group have the same number of valence electrons.

One-liner

Relative atomic mass is the mass of an atom of an element as compared to the mass of carbon-12.

One-liner

A positively charged ion in a compound is called a cation.

One-liner

Rutherford's gold foil experiment led to the discovery of the nucleus.