# Question 1e60c

Nov 9, 2016

#### Answer:

$1.66 \cdot {10}^{26}$

#### Explanation:

It's worth remembering that you can go from moles to molecules by using a single conversion factor.

More specifically, you can convert the number of moles of a molecular substance to number of molecules by using Avogadro's constant

$\textcolor{p u r p \le}{\overline{\underline{| \textcolor{w h i t e}{\frac{a}{a}} \textcolor{b l a c k}{\text{1 mole" = 6.022 * 10^(23)"molecules}} \textcolor{w h i t e}{\frac{a}{a}} |}}} \to$ Avogadro's constant

You are given moles and asked to find the number of molecules, so set up the conversion factor as

${\text{no. of molecules"/"1 mole" = (6.022 * 10^(23)"molecules CO"_2)/"1 mole CO}}_{2}$

Plug in your value to find

2.76 * 10^2 color(red)(cancel(color(black)("moles CO"_2))) * (6.022 * 10^(23)"molecules CO"_2)/(1color(red)(cancel(color(black)("mole CO"_2))))#

$= \textcolor{g r e e n}{\overline{\underline{| \textcolor{w h i t e}{\frac{a}{a}} \textcolor{b l a c k}{1.66 \cdot {10}^{26} {\text{molecules CO}}_{2}} \textcolor{w h i t e}{\frac{a}{a}} |}}}$

The answer is rounded to three sig figs.