How many grams of calcium hydride are needed to form 4.850 g of hydrogen gas?
To calculate the amount of calcium hydride needed to form 4.850 g of hydrogen gas, you need to use the molar ratio between calcium hydride (CaH2) and hydrogen gas (H2), which is 1:2. Therefore, you would need half as many grams of calcium hydride as the grams of hydrogen gas produced, so 2.425 g of calcium hydride would be needed.