The basic law of mass conservation states that, the total mass of products of a chemical reaction should be equal to the total mass of reactants in the same reaction.
Applying this law to the above problem, we find that:
Total mass of reactants = 46 + 96 = 142 grams
This means that the total mass of products (water + carbon dioxide) should be also 142 grams
Since 52 grams of water is produced, therefore,
mass of carbon dioxide = 142 - 52 = 90 grams
