If the oxidation state of central atom in `BH_3` is +3, then the oxidation states of the central atom in `SiH_4 and CH_4` are, respectively,

Options

A. + 4,-4
B. +4, +4
C. -4, +4
D. ` -4,-4`

Answer

To determine the oxidation states of the central atoms in SiH₄ and CH₄, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Oxidation States**: The oxidation state of an element in a compound is a measure of the degree of oxidation of that element. In a neutral compound, the sum of the oxidation states must equal zero.

2. **Analyzing CH₄ (Methane)**:
- The central atom is Carbon (C).
- Hydrogen (H) has an oxidation state of +1.
- Let the oxidation state of Carbon be \( x \).
- Since there are four Hydrogen atoms, the equation for the oxidation state can be set up as:
\[ x + 4(+1) = 0 \]
- Simplifying this gives:
\[ x + 4 = 0 \implies x = -4 \]
- Therefore, the oxidation state of Carbon in CH₄ is **-4**.

3. **Analyzing SiH₄ (Silane)**:
- The central atom is Silicon (Si).
- Similar to Carbon, Hydrogen (H) has an oxidation state of +1.
- Let the oxidation state of Silicon be \( y \).
- The equation for the oxidation state can be set up as:
\[ y + 4(+1) = 0 \]
- Simplifying this gives:
\[ y + 4 = 0 \implies y = -4 \]
- Therefore, the oxidation state of Silicon in SiH₄ is also **-4**.

4. **Final Answer**: The oxidation states of the central atoms in SiH₄ and CH₄ are both **-4**.

### Summary:
- Oxidation state of Carbon in CH₄ = -4
- Oxidation state of Silicon in SiH₄ = -4