Question

why do Rockets do not carry oxygen in the gaseous form
​

Answer 1

Jet engines draw oxygen into their engines from the surrounding air. Rockets do not have the luxury that jet planes have; they must carry oxygen with them into space, where there is no air. Solid rocket propellants, which are dry to the touch, contain both the fuel and oxidizer combined together in the chemical itself.

Answer 2

oxygen as a fuel to react with hydrogen can be stored in liquid form as it is far more dense than in a gaseous form.in addition to it oxygen react with hydrogen fuel and release energy as thrust will also generate some water in which astronauts can drink later!!