Fireworks, kno3 give only the names of the elements alphabetically, separating them with commas.

The elements present are potassium, nitrogen and oxygen.

Explanation:

Elements are defined as the substances in which same type of atoms are present. For Example: Sodium, Chlorine etc.

The chemical formula of the compound used in fireworks is

The chemical name for the compound is potassium nitrate.

This compound is formed by the combination of three elements. In 1 mole of potassium nitrate, 1 mole of potassium atom, 1 mole of nitrogen atom and 3 moles of oxygen atoms are present.

Hence, the elements present are potassium, nitrogen and oxygen.

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8