Together, nitrogen (N2) and oxygen (O2) by volume account for _____% of the gases composing the dry air in the lower atmosphere (below an altitude of 80 km
Nitrogen is around 78% and Oxygen is 21% so that make up a total of 99% of the air composition.
The 3rd most abundant gas in atmosphere is CO2.
Nitrogen and oxygen account for approximately 99% of the gases composing the dry air in the lower atmosphere (below an altitude of 80 km).
To find the answer to this question, we need to know the percentages of nitrogen and oxygen in dry air.
Dry air composition can vary slightly depending on location and other factors, but as a general approximation, we can consider dry air to be composed of approximately 78% nitrogen and 21% oxygen.
To calculate the combined percentage, we simply add these two percentages:
78% (nitrogen) + 21% (oxygen) = 99%
Therefore, nitrogen (N2) and oxygen (O2) by volume account for approximately 99% of the gases composing the dry air in the lower atmosphere below an altitude of 80 km.