In substance `Mg(HXO_(3))`, the oxidation number of X is :-

Options

A. 0
B. `+2`
C. `+3`
D. `+4`

Answer

To determine the oxidation number of the element X in the compound Mg(HXO₃), we can follow these steps:

### Step 1: Identify the oxidation states of known elements
- Magnesium (Mg) has an oxidation state of +2.
- Hydrogen (H) has an oxidation state of +1.
- Oxygen (O) has an oxidation state of -2.

### Step 2: Write the formula for the overall charge
The compound is neutral, meaning the sum of the oxidation states must equal zero. The formula can be expressed as:
\[ \text{Oxidation state of Mg} + \text{Oxidation state of H} + \text{Oxidation state of X} + \text{Oxidation state of O} = 0 \]

### Step 3: Set up the equation
For the compound Mg(HXO₃), we can express the oxidation states as follows:
- Oxidation state of Mg = +2
- Oxidation state of H = +1 (there is one H)
- Oxidation state of O = -2 (there are three O, so total = -2 × 3 = -6)
- Let the oxidation state of X be \( x \).

Thus, the equation becomes:
\[ +2 + (+1) + x + (-6) = 0 \]

### Step 4: Simplify the equation
Now, simplifying the equation:
\[ 2 + 1 + x - 6 = 0 \]
\[ x - 3 = 0 \]

### Step 5: Solve for x
Now, solving for \( x \):
\[ x = 3 \]

### Conclusion
The oxidation number of X in the substance Mg(HXO₃) is +3.

### Final Answer
The oxidation number of X is +3.

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