How many grams of calcium hydride are required to produce 4.56 L of hydrogen gas at 25.0 °C and 0.975 bar according to the chemical equation shown below? CaH₂(s) + 2H₂O(l) → Ca(OH)₂(aq) + 2H₂(g) A) 3.77 g B) 7.64 g C) 15.3 g D) 45.6 g

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Using the ideal gas law, calculate moles of H₂: PV = nRT. Convert 0.975 bar to atm (0.961 atm), and 4.56 L to moles using R = 0.0821 L·atm/mol·K and T = 298 K. Moles of H₂ = 0.182. From the equation, 1 mole of CaH₂ produces 2 moles of H₂, so moles of CaH₂ = 0.091. Molar mass of CaH₂ is 42.1 g/mol, so mass = 0.091 mol × 42.1 g/mol = 3.77 g.

How Many Grams of Calcium Hydride Are Required to Produce