(i) Draw the atom

(i) Magnesium: Symbol = Mg

Atomic number = 12

Protons = 12

Electrons = 12

Electronic configuration = 2, 8, 2

Atomic structure:

Silicon: Symbol = Si

Atomic number = 14

Protons = 14

Electrons = 14

Electronic configuration = 2, 8, 4

Atomic structure:

Sulphur: Symbol = S

Atomic number = 16

Protons = 16

Electrons = 16

Electronic configuration = 2, 8, 6

Atomic structure:

(ii)

Atomic number that can be determined from the atomic structure is 13

Mass number is 13 + 14 = 27