Question

$1.4$ moles of phosphorus trichloride are present in a sample. How many atoms are there in the sample?

• A. $5.6$
• B. $34$
• C. $2.4\times {10}^{23}$
• D. $3.372\times {10}^{24}$

Answer 1

The correct option is D $3.372\times {10}^{24}$

1 mol $PC{l}_3=6.022\times {10}^{23}$ molecules

1.4 mol $PC{l}_3=1.4\times 6.022\times {10}^{23}=8.43\times {10}^{23}$ molecules

Number of atoms present in 1 molecule of $PC{l}_3=4$

Number of atoms in $8.43\times {10}^{23}moleculesofPC{l}_3=4\times 8.43\times {10}^{23}$ atoms

$=33.72\times {10}^{23}$

$=3.372\times {10}^{24}$ atoms.

Hence, option $D$ is correct.