The total number of electrons present in 3.2 g of methane are :

Explanation

To find the total number of electrons present in 3.2 g of methane (CH₄), we can follow these steps:

### Step 1: Determine the molecular weight of methane (CH₄)
- The molecular weight of methane is calculated as follows:
- Carbon (C) has an atomic weight of 12 g/mol.
- Hydrogen (H) has an atomic weight of 1 g/mol, and there are 4 hydrogen atoms in methane.

Therefore, the molecular weight of CH₄ = 12 + (4 × 1) = 16 g/mol.

### Step 2: Calculate the number of moles of methane in 3.2 g
- To find the number of moles, we use the formula:
\[ \text{Number of moles} = \frac{\text{mass (g)}}{\text{molar mass (g/mol)}} \]

For 3.2 g of CH₄:
\[ \text{Number of moles} = \frac{3.2 \, \text{g}}{16 \, \text{g/mol}} = 0.2 \, \text{mol} \]

### Step 3: Calculate the number of molecules in 0.2 moles of methane
- Using Avogadro's number (6.02 × 10²³ molecules/mol), we can find the number of molecules:
\[ \text{Number of molecules} = \text{Number of moles} \times \text{Avogadro's number} \]

\[ \text{Number of molecules} = 0.2 \, \text{mol} \times 6.02 \times 10^{23} \, \text{molecules/mol} = 1.204 \times 10^{23} \, \text{molecules} \]

### Step 4: Determine the number of electrons in one molecule of methane
- Each molecule of CH₄ contains:
- 6 electrons from carbon (C)
- 4 electrons from 4 hydrogen (H) atoms (1 electron each)

Therefore, the total number of electrons in one molecule of CH₄ = 6 + 4 = 10 electrons.

### Step 5: Calculate the total number of electrons in 1.204 × 10²³ molecules of methane
- To find the total number of electrons:
\[ \text{Total electrons} = \text{Number of molecules} \times \text{Electrons per molecule} \]

\[ \text{Total electrons} = 1.204 \times 10^{23} \, \text{molecules} \times 10 \, \text{electrons/molecule} = 1.204 \times 10^{24} \, \text{electrons} \]

### Final Answer
The total number of electrons present in 3.2 g of methane is approximately \( 1.204 \times 10^{24} \) electrons.

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