Answer:
nitrogen
Explanation:
The atmosphere contains many gases, most in small amounts, including some pollutants and greenhouse gases. The most abundant gas in the atmosphere is nitrogen, with oxygen second. Argon, an inert gas, is the third most abundant gas in the atmosphere. Why do I care?
Answer:

Explanation:
Hello,
In this case, we can study the ideal gas equation that relates temperature, volume, pressure and moles as shown below:

Thus, since we are asked to compute the pressure y simply solve for it as follows:

Best regards.
12/12= 1 mol
this is because: amount of moles=mass/relative formula mass and the relative formula mass of carbon is 12
Answer:
390.6 gram
Explanation:
Mass in gram = no of moles × molar mass
Mass in gram = 21.7×18
= 390.6 gram
I believe it is answer 2 and 4