By volume, they are:Oxygen (42%), Sodium (29%),
Hydrogen (22%),
Helium (6%),
rest (traces).
Hydrogen, Helium
The dominant atmospheric gases on Mercury are oxygen, sodium, hydrogen, helium, and potassium. However, the atmosphere on Mercury is very thin, with a pressure about 10^-15 times that of Earth's atmosphere.
well Mercury has no gas
The atmospheric pressure is negligible.
Their gravity is too weak to hold on to atmospheric gases.
I think mercury goten methane,nitrogen etc.
If you mean what is the biggest planet without an atmosphere, then the answer would be Mercury.
mercury
a very thin amount of vaporized metal
Mercury's atmosphere is so tenuous as to sometimes be considered absent, or that the planet lacks one. Only trace amounts of some gases are detectable. It is sometimes referred to as the planet's exosphere - from which we could imply that, unlike Earth, 'space' begins at Mercury's surface. By contrast, the atmospheric pressure on Venus is over 90 times that of Earth at sea level.
Yes, but in very small quantities. Very very small quantities, Mercury's atmosphere is basically a vacuum.
The whirlpool swirled and eddied. The atmospheric gases eddied in the planet's atmosphere.