The mass of 0.5 moles of methane is

Explanation

To find the mass of 0.5 moles of methane (CH₄), we can follow these steps:

### Step 1: Identify the molecular formula of methane.
Methane is represented by the chemical formula CH₄.

### Step 2: Calculate the molecular mass of methane.
To calculate the molecular mass, we need to add the atomic masses of its constituent elements:
- Carbon (C) has an atomic mass of approximately 12 g/mol.
- Hydrogen (H) has an atomic mass of approximately 1 g/mol. Since there are 4 hydrogen atoms in methane, we multiply the atomic mass of hydrogen by 4.

So, the calculation is:
- Molecular mass of CH₄ = (1 × atomic mass of C) + (4 × atomic mass of H)
- Molecular mass of CH₄ = (1 × 12 g/mol) + (4 × 1 g/mol) = 12 g/mol + 4 g/mol = 16 g/mol.

### Step 3: Determine the mass of 0.5 moles of methane.
We know that 1 mole of methane has a mass of 16 grams. To find the mass of 0.5 moles, we can use the following calculation:
- Mass of 0.5 moles of CH₄ = 0.5 moles × mass of 1 mole of CH₄
- Mass of 0.5 moles of CH₄ = 0.5 × 16 g = 8 g.

### Conclusion:
The mass of 0.5 moles of methane is 8 grams.

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