Question

What is the molar mass of compound represented by following structure formula?

• A. \(36\text{ g mol}^{-1}\)
• B. \(46\text{ g mol}^{-1}\)
• C. \(22\text{ g mol}^{-1}\)
• D. \(32\text{ g mol}^{-1}\)

Hint:

Line structures: each vertex represents a carbon atom—always count hydrogens accordingly.

Answer 1

The Correct Option is B

Concept:
Molar mass is calculated by summing atomic masses of all atoms present in the compound. Step 1: Identify the structure. The given structure shows a two-carbon chain with an \(-OH\) group: \[ \text{CH}_3 - \text{CH}_2 - \text{OH} \] This is ethanol.
Step 2: Count atoms.

• Carbon = 2 atoms → \(2 \times 12 = 24\)
• Hydrogen = 6 atoms → \(6 \times 1 = 6\)
• Oxygen = 1 atom → \(16\)

Step 3: Calculate molar mass. \[ 24 + 6 + 16 = 46 \]
Step 4: Conclusion. Molar mass = \(46\text{ g mol}^{-1}\)