Answer to Question #346574 in General Chemistry for Han

Question

How many grams of H2O are needed if 41.85g of O2 are to be produced from the reaction below? Show the solution

2K2O2 + 2H2O -----> 4KOH + O2

Answer 1

M_r (H₂O) = 18 g/mol

M_r (O₂) = 32 g/mol

2K₂O₂ + 2H₂O = 4KOH + O₂

According to the above reaction, 2 mol (36 g) of H₂O reacts to form 1 mol (32 g) of O₂. We find how many g of H₂O must be reacted to form 41.85 g of O₂ :

36g H₂O —> 32g O₂

X —> 41,85g O₂

X = 36 * 41,85 / 32 = 47,08 g

ANSWER: 47,08 g H₂O