Question

Use the table of molar masses to complete the question. Do NOT use any other values except the ones provided in the table below.

Element Molar Mass (g/mol)
carbon 12.01
hydrogen 1.01
oxygen 16.00
A chemist will use a sample of 30g of glucose (
C
6
H
12
O
6
) in an experiment. Determine the number of moles of glucose the chemist will use based on the molar mass values provided in the table. (Your value should be rounded to 2 decimal places; i.e. the hundredths place).

(2 points)
The number of moles the chemist will use is:
moles.

Answer 1

To determine the number of moles of glucose (C₆H₁₂O₆) in a 30 g sample, we first need to calculate the molar mass of glucose using the provided molar masses for carbon, hydrogen, and oxygen.

1. **Calculate the molar mass of glucose (C₆H₁₂O₆)**:
- Molar mass of Carbon (C): 12.01 g/mol
- Molar mass of Hydrogen (H): 1.01 g/mol
- Molar mass of Oxygen (O): 16.00 g/mol

Molar mass of glucose:
\[
\text{Molar mass of } C_6H_{12}O_6 = (6 \times \text{Molar mass of C}) + (12 \times \text{Molar mass of H}) + (6 \times \text{Molar mass of O})
\]
\[
\text{Molar mass of } C_6H_{12}O_6 = (6 \times 12.01) + (12 \times 1.01) + (6 \times 16.00)
\]
\[
= 72.06 + 12.12 + 96.00 = 180.18 \, \text{g/mol}
\]

2. **Calculate the number of moles of glucose in 30 g**:
\[
\text{Number of moles} = \frac{\text{mass (g)}}{\text{molar mass (g/mol)}}
\]
\[
= \frac{30 \, \text{g}}{180.18 \, \text{g/mol}} \approx 0.1665 \, \text{moles}
\]

3. **Round to two decimal places**:
\[
\text{Number of moles} \approx 0.17 \, \text{moles}
\]

The number of moles the chemist will use is: **0.17 moles**.