The answer to the question is C
Answer:
7.5 g of hydrogen gas reacts with 50.0 g oxygen gas to form 57.5 g of water.
Explanation:
Here we have the check if the mass of the reactants is equal to the mass of the products.
Reactants

Products

The data is consistent with the law of conservation of matter.
Reactants

Products

The data is not consistent with the law of conservation of matter.
Reactant

Products

The data is not consistent with the law of conservation of matter.
Only the first data is consistent with the law of conservation of matter.
Its atomic symbol is H and its atomic number is one. Hydrogen; Hydrogen, H, is a chemical element with atomic number 1. At standard temperature and pressure, hydrogen is a colorless, odorless, nonmetallic, tasteless, highly flammable diatomic gas with the molecular formula H2.
Hydrogen is easily the most abundant element in the universe. It is found in the sun and most of the stars, and the planet Jupiter is composed mostly of hydrogen. On Earth, hydrogen is found in the greatest quantities as water.