Question

how many water molecules are in 5.2 moles of water? 5.2 molecules 3.1 x 10^24 molecules 6.0 x 10^23 molecules 8.6 x 10^-24 molecules

Explanation:

Step1: Recall Avogadro's number

Avogadro's number $N_A = 6.022\times 10^{23}\text{ molecules/mol}$.

Step2: Calculate number of molecules

We use the formula $N = n\times N_A$, where $n = 5.2\text{ mol}$. So $N=5.2\times6.022\times 10^{23}$.

Step3: Perform the multiplication

$5.2\times6.022\times 10^{23}\approx31.3144\times 10^{23}=3.13144\times 10^{24}\approx3.1\times 10^{24}$ molecules.

Answer:

B. $3.1\times 10^{24}$ molecules