Question

at constant temperature and pressure 2 litres of hydrogen gas reacts with 1 litre of Oxygen gas to produce 2 litre of water vapour to what this is accordance with​

Answer 1

refer to ncert class 11 chemistry...ie gay lussacs law of combining volumes

Answer 2

Answer:

Law of gaseous volumes

$H_{2} (g)\\2Litres$ + $O_{2} (g)\\2Litres$ ⟶ $H_{2}O\\2Litres$

When the volume is held constant, the pressure of a given mass of gas varies directly with the absolute temperature, according to Gay Lusaacc's law of gaseous volume. In other words, while the mass is constant and the volume is constant, the pressure produced by a gas is proportional to the temperature of the gas.