Question

1. calculate the number of molecules in 2.5 mol of sucrose.

Explanation:

Step1: Recall Avogadro's number

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

Step2: Calculate number of molecules

The number of molecules ($N$) is given by $N = n\times N_A$, where $n = 2.5$ mol. So $N=2.5\times6.022\times 10^{23}$.
$N = 15.055\times 10^{23}=1.5055\times 10^{24}\approx1.51\times 10^{24}$ molecules.

Answer:

1.51×10^24 molecules