Question

under certain conditions, the substance water can be broken down to form hydrogen and oxygen. water → hydrogen + oxygen 30.40g 3.4g if 30.40 grams of water react to form 3.4 grams of hydrogen, how many grams of oxygen must simultaneously be formed? grams oxygen

Explanation:

Step1: Apply law of conservation of mass

According to the law of conservation of mass, the mass of reactants equals the mass of products in a chemical - reaction. Here, water is the reactant and hydrogen and oxygen are the products.

Step2: Calculate mass of oxygen

Let the mass of oxygen be $m$. The mass of water is 30.40 g and the mass of hydrogen is 3.4 g. So, $m=30.40 - 3.4$.
$m = 27$ g

Answer:

27 grams