Which of the following contains largest number of carbon atoms ?

Options

A. 15 gm ethane ,`C_(2)H_(6)`
B. 40.2 gm sodium oxalate ,`Na_(2)C_(2)O_(4)`
C. 72 gm glucose, `C_(6)H_(12)O_(6)`
D. 35 gm pentene,`C_(5)H_(10)`

Answer

To determine which of the given compounds contains the largest number of carbon atoms, we will calculate the number of carbon atoms in each compound based on the provided weights. We will use the formula for moles and the molecular weights of each compound.

### Step-by-Step Solution:

1. **Calculate the number of moles of Ethane (C₂H₆)**:
- Given weight = 15 grams
- Molecular weight of C₂H₆ = (2 × 12) + (6 × 1) = 24 + 6 = 30 g/mol
- Moles of C₂H₆ = weight / molecular weight = 15 g / 30 g/mol = 0.5 moles
- Number of carbon atoms = moles × number of carbon atoms per molecule × Avogadro's number
- Number of carbon atoms = 0.5 moles × 2 × 6.02 × 10²³ = 6.02 × 10²³ carbon atoms

2. **Calculate the number of moles of Sodium Oxalate (Na₂C₂O₄)**:
- Given weight = 40.2 grams
- Molecular weight of Na₂C₂O₄ = (2 × 23) + (2 × 12) + (4 × 16) = 46 + 24 + 64 = 134 g/mol
- Moles of Na₂C₂O₄ = weight / molecular weight = 40.2 g / 134 g/mol = 0.3 moles
- Number of carbon atoms = 0.3 moles × 2 × 6.02 × 10²³ = 3.6 × 10²³ carbon atoms

3. **Calculate the number of moles of Glucose (C₆H₁₂O₆)**:
- Given weight = 72 grams
- Molecular weight of C₆H₁₂O₆ = (6 × 12) + (12 × 1) + (6 × 16) = 72 + 12 + 96 = 180 g/mol
- Moles of C₆H₁₂O₆ = weight / molecular weight = 72 g / 180 g/mol = 0.4 moles
- Number of carbon atoms = 0.4 moles × 6 × 6.02 × 10²³ = 14.4 × 10²³ carbon atoms

4. **Calculate the number of moles of Pentene (C₅H₁₀)**:
- Given weight = 35 grams
- Molecular weight of C₅H₁₀ = (5 × 12) + (10 × 1) = 60 + 10 = 70 g/mol
- Moles of C₅H₁₀ = weight / molecular weight = 35 g / 70 g/mol = 0.5 moles
- Number of carbon atoms = 0.5 moles × 5 × 6.02 × 10²³ = 15.05 × 10²³ carbon atoms

### Summary of Results:
- Ethane: 6.02 × 10²³ carbon atoms
- Sodium Oxalate: 3.6 × 10²³ carbon atoms
- Glucose: 14.4 × 10²³ carbon atoms
- Pentene: 15.05 × 10²³ carbon atoms

### Conclusion:
The compound with the largest number of carbon atoms is **Pentene (C₅H₁₀)** with **15.05 × 10²³ carbon atoms**.

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