A metal M forms an ionic compound X of formula `M_(2)(SO_(4))_(3)`.
(a) Identify the cation in X.
(b) Given the relative formula mass of X is 392, determine the relative atomic mass of metal M.
(c) (i) What is the formula of the nitrate of metal M?
(ii) Calculate the relative formula mass of nitrate compound in (c)(i).

Explanation

Let's solve the question step by step.

### Step 1: Identify the cation in X
The given formula for the ionic compound is \( M_2(SO_4)_3 \).

- In this formula, \( M \) represents the metal cation and \( SO_4 \) represents the sulfate anion.
- The sulfate ion \( SO_4^{2-} \) has a charge of -2. Since there are 3 sulfate ions in the compound, the total negative charge contributed by the sulfate ions is \( 3 \times (-2) = -6 \).
- To balance this charge, the total positive charge from the cations must be +6. Since there are 2 cations of \( M \), each must have a charge of +3.
...