To inflate a life raft with hydrogen to a volume of \(25.0 \mathrm{~L}\) at \(25^{\circ} \mathrm{C}\) and \(1.10 \mathrm{~atm}\), what mass of calcium hydride must react with water?

n ≈ 1.102 moles of H₂ gas #tag_title#Step 2: Determine the moles of calcium hydride needed#tag_content#Next, we will use the balanced chemical equation for the reaction of calcium hydride and water to find the moles of calcium hydride required: CaH₂(s) + 2 H₂O(l) → Ca(OH)₂(aq) + 2 H₂(g) From the balanced equation, we can see that 1 mole of calcium hydride produces 2 moles of hydrogen gas. Therefore, we can calculate the moles of calcium hydride needed: moles of CaH₂ = (moles of H₂) / 2 moles of CaH₂ = 1.102 moles of H₂ / 2 moles of CaH₂ ≈ 0.551 moles #tag_title#Step 3: Convert moles of calcium hydride to mass#tag_content#Finally, we will convert the moles of calcium hydride to mass using its molar mass. The molar mass of CaH₂ is: Molar mass of CaH₂ = 40.08 g/mol (Ca) + 1.01 g/mol (H) × 2 = 42.10 g/mol Now, we can calculate the mass of calcium hydride needed: Mass of CaH₂ = (moles of CaH₂) × (molar mass of CaH₂) Mass of CaH₂ = 0.551 moles × 42.10 g/mol Mass of CaH₂ ≈ 23.18 g Therefore, approximately 23.18 grams of calcium hydride is needed to inflate the life raft.