Question

How much sugar $\left(C_{12}{H}_{22}{O}_{11}\right)$ will be required if each person on earth is given $100$ molecules of sugar? The population of the earth is $3\times {10}^{10}$.

• A. $170.43\times {10}^{-10}g$
• B. $170.43\times {10}^{-11}g$
• C. $340.86\times {10}^{-11}g$
• D. $340.86\times {10}^{-10}g$

Answer 1

The correct option is B $170.43\times {10}^{-11}g$

The sugar given to the entire population on earth is $3\times {10}^{10}\times {10}^2=3\times {10}^{12}$ molecules.
One mole $(6\times {10}^{23})$ molecules of sugar corresponds to $342$ g.
Hence, $3\times {10}^{12}$ molecules of sugar corresponds to $\frac{3\times {10}^{12}}{6\times {10}^{23}}\times 342=170.43\times {10}^{-11}$ g.
Therefore, sugar required is $170.43\times {10}^{-11}$ g.