`(NH_(4))_(2)SO_(4)FeSO_(4)6H_(2)O`, is this compound alum or not? 

Explanation

To determine whether the compound \((NH_4)_2SO_4 \cdot FeSO_4 \cdot 6H_2O\) is an alum or not, we can follow these steps:

### Step 1: Understand the Definition of Alum
Alums are a specific type of double salt that typically have the general formula:
\[ M_2SO_4 \cdot N_2(SO_4)_3 \cdot 24H_2O \]
where \(M\) is a monovalent cation (like \(Na^+, K^+, Rb^+, Cs^+, NH_4^+\)) and \(N\) is a trivalent cation (like \(Al^{3+}, Cr^{3+}, Fe^{3+}\)).

### Step 2: Analyze the Given Compound
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