apply the law of constant proportion to calculate the mass of oxygen that will be used in combustion of 5gm of hydrogen gas

Hi ekanshsingh97,

The question framed by you can be best answered by the law of conservation of mass as the reaction conditions for only one reaction is given.

The law of constant proportion can only be fitted into it if we consider the balanced chemical equation for the original reaction.

From the above equation, it can be inferred that

  4g of hydrogen react with 32 g of oxygen.

Thus, 5g of hydrogen react with

Hope, you got the answer to your question.

Best wishes!!