Question

calculate the number of molecules in 3 mol of carbon dioxide (co₂).
1.807×10²⁴
6.022×10²³
2.007×10²³
5.421×10²⁴

Explanation:

Step1: Recall Avogadro's number

Avogadro's number ($N_A$) is $6.022\times 10^{23}$ molecules/mol.

Step2: Calculate number of molecules

We use the formula $N = n\times N_A$, where $n = 3$ mol and $N_A=6.022\times 10^{23}$ molecules/mol. So $N=3\times6.022\times 10^{23}= 1.8066\times 10^{24}\approx1.807\times 10^{24}$ molecules.

Answer:

1. $1.807\times 10^{24}$