Question

if 3 g of h2 reacts with 30 g of o2 to yield h2o then the maximum amount of h20 that can be formed is​

Answer 1

The balanced chemical equation, for the reaction is :-

2H₂ + O₂ → 2H₂O

Number of moles of H₂ :-

= Given Mass/Molar mass

= 3/2

= 1.5 moles

Number of moles of O₂ :-

= Given Mass/Molar mass

= 30/32

= 0.9375 mole

According to the balanced equation, 2 moles of H₂ reacts with 1 mole of O₂. Hence, 1.5 mole of H₂ will react with :-

= 1.5/2

= 0.75 mole of O₂.

Here, we are given more moles of O₂ than H₂ therefore, O₂ is in excess and some of it will remain unreacted when the reaction is over. So, H₂ is the limiting reagent and will control the amount of product.

Now, again from the equation :-

∵ 4g of H₂ → 36g of H₂O

∴ 3g of H₂ → 3×36/4 = 27g of H₂O

Thus, the maximum amount of H₂O that can be formed is 27g .