Science, Chemistry, periodic table

Nitric Acid

HNO3

Sulphuric acid

H2SO4

Sodium Hydroxide

NaOH

calcium hydroxide

Ca(OH)2

copper oxide

CuO

hydrochloric acid

HCl

Oxygen

O2

Protons

positively charged particles found in the nucleus

Neutrons

the particles of the nucleus that have no charge

Electron

A subatomic particle that has a negative charge

The atomic number of an element is the number of protons

Helium, He has 2 protons so has an atomic number of 2

The mass number of an element is the number of protons + neutrons

e.g Helium, He has 2 protons and 2 neutrons so 2+2 = 4. Therefore the mass number of He is 4.