A person requires `2870kcal` of energy to lead normal daily life. If heat of combustion of cane sugar is `-1349kcal`, then his daily comsumption of sugar is `:`

Options

A. 728 g
B. 0.728 g
C. 342 g
D. 0.342 g

Explanation

To solve the problem, we need to determine how much cane sugar is required to provide a person with 2870 kcal of energy, given that the heat of combustion of cane sugar is -1349 kcal per mole.

### Step-by-Step Solution:

1. **Understand the Heat of Combustion**:
The heat of combustion of cane sugar (sucrose) is given as -1349 kcal. This means that when one mole of cane sugar is completely burned, it releases 1349 kcal of energy.

2. **Determine the Molar Mass of Cane Sugar**:
The molar mass of sucrose (C12H22O11) is approximately 342 grams per mole.

3. **Calculate Energy Produced per Gram of Sugar**:
To find out how much energy is produced per gram of sugar, we can use the following formula:
\[ \text{Energy per gram} = \frac{\text{Heat of combustion}}{\text{Molar mass}} = \frac{1349 \text{ kcal}}{342 \text{ g}} \approx 3.94 \text{ kcal/g} \]

4. **Calculate Daily Sugar Consumption**:
Now, we need to find out how many grams of sugar are required to meet the daily energy requirement of 2870 kcal:
\[ \text{Daily consumption of sugar} = \frac{\text{Daily energy requirement}}{\text{Energy per gram}} = \frac{2870 \text{ kcal}}{3.94 \text{ kcal/g}} \approx 728 \text{ g} \]

5. **Final Answer**:
Therefore, the daily consumption of sugar required to meet the energy needs is approximately **728 grams**.