The primary gas in a volcano is: carbon dioxide, sulfur dioxide, water vapor, nitrogen.

Water vapor

Explanation:

The magma consists of dissolved gases when these gases produce the force the volcanic eruption takes place. The volcanic gases come out and their volume is increased tremendously. The gases present in the volcano are listed below:

The volcanic gases consist of water vapors, carbon dioxide, and sulfur.

These three are the primary gases but the water is present in a higher amount.

The percentage of water is 60%.

The carbon dioxide present in 10-40%.

Other gases present in volcanos are nitrogen, argon, helium, neon methane, and hydrogen.

Hope this helps, Let me know if I am wrong ( I am pretty sure that am not) but let me know anyway..., OH! and Good LUCK! :D ;P

the bal will not change its velocity.

current flows in a wire