speed of sound in oxygen(o2) at a certain temperature is 460m/s. the speed of sound in He at the same temperature will be( assume both gases are ideal)

As velocity is inversely proportional to square root of molecular mass. And as weight of He is 1/8 the of O2. So sound speed of He is 460(2√2).Hope it clears. If u have doubts then please clearify. And if u like my answer then please approve answer