What planet has the least amount of gas?

Mercury is the planet with the least amount of gas in our solar system. It is a terrestrial planet primarily composed of rock and metal, with a very thin atmosphere made up mostly of oxygen, sodium, hydrogen, helium, and potassium. Due to its proximity to the Sun and low gravity, it lacks a significant gaseous envelope. As a result, Mercury has minimal atmospheric retention compared to the gas giants like Jupiter and Saturn.