Equal volumes of h2 and o2 are placed in a balloon and then ignited. assuming that the reaction goes to completion, which gas will remain in excess 2 o 2h both are in equal proportion oxygen water hydrogen

Answer : The correct option is, Oxygen.

Explanation :

The given balanced chemical reaction is:

From the balanced reaction we conclude that, 2 moles of hydrogen react with 1 mole of oxygen to give 2 moles of water.

As we know that at STP, 1 mole of gas contains 22.4 L volume of gas. That means there is a direct relation between the moles and volume of gas.

So we ca say that,

2 unit volume of hydrogen gas will react with 1 unit volume of oxygen gas.

As per question, the volume of gasses are equal that means half of oxygen gas will be consumed against the complete volume of hydrogen gas.

Thus, the gas that will remain in excess is oxygen gas.

the answer is barium and copper bromide