Question

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)
Responses

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

Neither are correct. It would have been 1112g, because there are 2 H2 to 1 O2.
Neither are correct. It would have been 1112g, because there are 2 H 2 to 1 O 2 .

Neither are correct. It was 2000g because the equation shows 2H2O.
Neither are correct. It was 2000g because the equation shows 2H 2 O.

Student A, because the water was not measured to start with.
Student A, because the water was not measured to start with.
Skip to navigation

Answer 1

Student B, because of the law of conservation of matter. The total mass of products is 112 g + 888 g = 1000 g, so 1000 g of water must have been present initially.