Question

verify your calculation. in your set-up, do your units cancel?
mass of magnesium (g) 0.019
moles of magnesium (mol)

Explanation:

Step1: Recall molar mass of Mg

Molar mass of Mg is \( 24.305 \, \text{g/mol} \). Formula to find moles: \( \text{Moles} = \frac{\text{Mass}}{\text{Molar Mass}} \)

Step2: Substitute values

Mass of Mg is \( 0.019 \, \text{g} \), molar mass \( 24.305 \, \text{g/mol} \). So, \( \text{Moles} = \frac{0.019 \, \text{g}}{24.305 \, \text{g/mol}} \)

Step3: Calculate

\( \frac{0.019}{24.305} \approx 0.000782 \, \text{mol} \) (units: g cancels, gives mol)

Answer:

\( \approx 0.000782 \, \text{mol} \) (or more precisely, \( \frac{0.019}{24.305} \approx 7.82 \times 10^{-4} \, \text{mol} \))