# Question 3fa99

Aug 20, 2017

$1.48 \times {10}^{24}$ ${\text{molecules NH}}_{3}$

#### Explanation:

We're asked to find the number of molecules of ${\text{NH}}_{3}$ present in $2.45$ ${\text{mol NH}}_{3}$.

To do this, we can use the fact that one mole of any substance contains ${\underbrace{6.022 \times {10}^{23}}}_{\text{Avogadro's number}}$ particles of that substance.

Therefore, we have

2.45cancel("mol NH"_3)((6.022xx10^23color(white)(l)"molecules NH"_3)/(1cancel("mol NH"_3)))

= color(red)(ulbar(|stackrel(" ")(" "1.48xx10^24color(white)(l)"molecules NH"_3" ")|)

This goes for any substance as well. That is to say, $2.45$ moles of carbon dioxide also contains color(red)(1.48xx10^24color(white)(l)"molecules"# of ${\text{CO}}_{2}$.