How many moles are in 15.0 g AsH_(3) 1200 2.3 0.19 5.2 0.44

To determine the number of moles in 15.0 g of $AsH_{3}$, we need to use the molar mass of $AsH_{3}$.<br /><br />The molar mass of $AsH_{3}$ is calculated as follows:<br />- Arsenic (As) has a molar mass of approximately 74.92 g/mol.<br />- Hydrogen (H) has a molar mass of approximately 1.01 g/mol.<br /><br />Since $AsH_{3}$ has one arsenic atom and three hydrogen atoms, its molar mass is:<br />\[ \text{Molar mass of } AsH_{3} = 74.92 \, \text{g/mol} + 3 \times 1.01 \, \text{g/mol} = 74.92 \, \text{g/mol} + 3.03 \, \text{g/mol} = 77.95 \, \text{g/mol} \]<br /><br />Now, we can calculate the number of moles in 15.0 g of $AsH_{3}$ using the formula:<br />\[ \text{Number of moles} = \frac{\text{Mass}}{\text{Molar mass}} \]<br /><br />Substituting the given values:<br />\[ \text{Number of moles} = \frac{15.0 \, \text{g}}{77.95 \, \text{g/mol}} \approx 0.192 \, \text{moles} \]<br /><br />Therefore, the correct answer is 0.19 moles.