Question

How many moles of iridium are in 26.4 g of iridium?
a. 1 mol
b. 1.37 10-1 mol
c. 5.06 103 mol
d. 7.29 mol

Answer 1

B. 1.37 10-1 mol of iridium

Answer 2

Answer: b. [tex]1.37\times 10^{-1}moles[/tex]

Explanation:

According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number $6.023\times 10^{23}$ of particles.

To calculate the moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}$

$\text{Number of moles of iridium}=\frac{26.4g}{192g/mol}=0.137moles=1.37\times 10^{-1}moles$

Thus $1.37\times 10^{-1}moles$ of iridium are in 26.4 g of iridium.