Question

how many molecules are in 0.75 moles of c2h2?
?×10^? molecules of c2h2
remember: 1 mole = 6.02×10^23 molecules
enter the coefficient in the green box and the exponent in the yellow box.

Explanation:

Step1: Recall Avogadro's number

1 mole of any substance contains $6.02\times 10^{23}$ molecules.

Step2: Calculate number of molecules

To find the number of molecules in 0.75 moles of $C_2H_2$, we multiply the number of moles by Avogadro's number. So, $0.75\times6.02\times 10^{23}=(0.75\times6.02)\times 10^{23}=4.515\times 10^{23}$.

Answer:

Coefficient: 4.515
Exponent: 23