What is the formula of nickel (ll) nitrate hexahydrate? (a) NiNO3.6H2O (b) Ni2NO3.6H2O (c) Ni (NO3) 2.6H2O (d) NiNO3.12H2O e) Ni (NO3) 2.12H2O

C) Ni (NO₃) ₂.6H₂O

Explanation:

Given:

Formula name : nickel (II) nitrate hexahydrate

To determine:

The molecular formula

Explanation:

In the given compound:

Nickel is a transition metal with the symbol Ni and occurs as a cation

Nitrate is a polyatomic anion with a charge - 1 i. e. NO₃⁻

The roman numeral 'II' implies that the oxidation state of Ni is + 2

Since the compound is neutral the charge on the cation and anion needs to be balanced. As a result the molecular formula is: Ni (NO₃) ₂

Hexahydrate implies that there are six (hexa) molecules of water of hydration

The formula is therefore: Ni (NO₃) ₂.6H₂O

The formula of nickeI (II) nitrate hexahydrate is

Ni (NO3) 2.6H2O

So option (c) is correct.