Not so sure but i think neon
Answer:51.1%
Explanation:
Mass percent : It is defined as the mass of the given component present in the total mass of the compound. Formula used : First we have to calculate the mass of and . Mass of = 18 g/mole Mass of = 7 × 18 g/mole = 126 g/mole Mass of = 246.47 g/mole Now put all the given values in the above formula, we get the mass percent of in . Therefore, the mass percent of in is, 51.1%
I think it's B. Molecules collide more frequently