# What is the mass of 0.5 moles of "CO"_2 ?

Jun 26, 2018

$22$ grams.

#### Explanation:

We use the following formula

n("moles") = (m("mass"))/(M("molar mass"))

Rearranging this equation, we find that

$m = n \cdot M$

We are given the moles $\left(0.5\right)$, so we need to find the molar mass. I'm assuming you are given a table of molar values of elements such as carbon is $\text{12 g/mol}$..

So to find moles, we add all the molar values together

$M \left(\text{CO"_2) = M("C") + 2*M("O}\right)$

M("CO"_2) = (12 + 2*16) \ "g/mol"

M("CO"_2) = 44 \ "g/mol"

Therefore, we can then use the above-rearranged equation to find $m$:

$m = \text{0.5 moles" * "44 g/mol}$

$m = \text{22 g}$

Jun 27, 2018

$22$ grams

#### Explanation:

To find the mass of a certain number of moles of a substance, we multiply the number of moles of the substance by its molar mass.

Carbon dioxide $\left(C {O}_{2}\right)$ has a molar mass of $44.01 \setminus \text{g/mol}$. Here, there are $0.5 \setminus \text{mol}$ of the molecule. So, the mass of this sample is:

m=(44.01 \ "g")/(color(red)cancelcolor(black)"mol")*0.5color(red)cancelcolor(black)"mol"

$\approx 22 \setminus \text{g}$