A divalent metal has 12 equivalent weight. The molecular weight of its oxide is

Options

A. 16
B. 32
C. 40
D. 52

Explanation

To find the molecular weight of the oxide of a divalent metal with an equivalent weight of 12, we can follow these steps:

### Step 1: Understand the concept of equivalent weight
The equivalent weight of a substance is defined as the mass of that substance that combines with or displaces 1 mole of hydrogen or 8 grams of oxygen. For metals, the equivalent weight can be calculated using the formula:

\[ \text{Equivalent Weight} = \frac{\text{Molecular Weight}}{n} \]

where \( n \) is the valency of the metal.

### Step 2: Identify the valency of the metal
In this case, the metal is divalent, which means it has a valency of 2. Therefore, \( n = 2 \).

### Step 3: Use the equivalent weight to find the molecular weight
Given that the equivalent weight of the metal is 12, we can rearrange the formula to find the molecular weight:

\[ \text{Molecular Weight} = \text{Equivalent Weight} \times n \]

Substituting the known values:

\[ \text{Molecular Weight} = 12 \times 2 = 24 \]

### Step 4: Determine the molecular weight of the oxide
The oxide of the metal will combine with oxygen. Since the metal is divalent, it will combine with one atom of oxygen (which has a molecular weight of 16) to form the oxide. The molecular weight of the oxide can be calculated as follows:

\[ \text{Molecular Weight of Oxide} = \text{Molecular Weight of Metal} + \text{Molecular Weight of Oxygen} \]

Substituting the values we have:

\[ \text{Molecular Weight of Oxide} = 24 + 16 = 40 \]

### Final Answer
The molecular weight of the oxide is **40 g/mol**.

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