Question

Which of the following has the highest mass?

• A. $1$ mole of C atoms
• B. $\frac{1}{2}$ mole of $C{H}_4$
• C. $10$ ml of water
• D. $3.011\times {10}^{23}$ atoms of oxygen

Answer 1

The correct option is A $1$ mole of C atoms

A. 1 mole of $C$ atom contains the mass 12g

B. 1 mole of $C{H}_4$ contains $1\times 12$(atomic weight of carbon) + $4\times 1$ (atomic weight of hydrogen) $=16g$

$\Rightarrow$ 1 mole of $C{H}_4$ contains the mass of $16g$

$\frac{1}{2}$ mole of $C{H}_4$ contains $\frac{16}{2}=8g$

C. 1 ml of $H_{2}O$ contains 1 gram weight.

10 ml of $H_{2}O$ contains 10 grams weight

D. 1 mole of oxygen has the mass of 16g.

From Avogadro's rule, 1 mole contains $6.0223\times {10}^{23}atoms$

$\Rightarrow$ $6.022\times {10}^{23}$ atoms contains the mass of 16g

$\frac{6.022\times {10}^{23}atoms}{2}$ $=3.011\times {10}^{23}$ atoms contain $\frac{16g}{2}=8g$

$3.011\times {10}^{23}$ atoms contain $8g$

From above options, option A contains the highest mass.