Question

under certain conditions, water can be separated into oxygen and hydrogen gases according to the equation 2h₂o → 2h₂ + o₂. in a lab, 112g of hydrogen gas and 888g of oxygen gas were collected. student a says that the amount of water to start cannot be determined, but student b says that the water must have been 1000g. who is correct? (1 point) neither are correct. it would have been 1112g, because there are 2 h₂ to 1 o₂. neither are correct. it was 2000g because the equation shows 2h₂o. student b, because of the law of conservation of matter. student a, because the water was not measured to start with.

Explanation:

Step1: Recall the law of conservation of matter

In a chemical reaction, the total mass of reactants equals the total mass of products.

Step2: Calculate the total mass of products

The mass of hydrogen gas is 112g and the mass of oxygen gas is 888g. The total mass of products is $112 + 888=1000$g.

Step3: Determine the amount of water

According to the law of conservation of matter, the mass of water (reactant) must be equal to the total mass of the products (hydrogen and oxygen gases), which is 1000g. So Student B is correct.

Answer:

Student B, because of the law of conservation of matter.