How many grams of calcium metal is required to react with 7.75 g water to produce calcium hydroxide and hydrogen gas?
A) 8.62 g
B) 34.5 g
C) 4.31 g
D) 40.1 g
E) 17.2 g

Question

Quizplus · Accepted Answer

The reaction between calcium and water is represented by the equation: Ca + 2H2O → Ca(OH)2 + H2. From the molar masses, we know that 40.08 g of Ca reacts with 18.015 g of H2O. Given 7.75 g of H2O, we use the ratio from the balanced equation to find the mass of Ca needed: (40.08 g Ca / 18.015 g H2O) * 7.75 g H2O = 8.62 g Ca.

How Many Grams of Calcium Metal Is Required to React