Question

How many atoms are there in 14.3 g of xenon?

Answer 1

Answer:

6.56 × 10²² atoms Xe

Explanation:

Step 1: Find conversions

Molar Mass Xe - 131.29 g/mol

Avagadro's Number: 6.022 × 10²³

Step 2: Use Dimensional Analysis

$14.3 \hspace{3} g \hspace{3} Xe(\frac{1 \hspace{3} mol \hspace{3} Xe}{131.29 \hspace{3} g \hspace{3} Xe} )(\frac{6.022(10)^{23} \hspace{3} atoms \hspace{3} Xe}{1 \hspace{3} mol \hspace{3} Xe} )$ = 6.55911 × 10²² atoms Xe

Step 3: Simplify

We have 3 sig figs.

6.55911 × 10²² atoms Xe ≈ 6.56 × 10²² atoms Xe