The oxygen proportion in dry air is closest to which value?
Answer and explanation
Correct answer: About 21%
Oxygen forms approximately 21% of dry air by volume, so option A is correct. Nitrogen is the dominant gas at about 78%, argon is slightly below 1%, and carbon dioxide is far below 1%; therefore the alternatives represent other atmospheric proportions rather than oxygen. The word dry is important because it excludes variable water vapour from the usual composition calculation.
Frequently asked questions
What is the correct answer to this question?
About 21%
Why is this the correct answer?
Oxygen forms approximately 21% of dry air by volume, so option A is correct. Nitrogen is the dominant gas at about 78%, argon is slightly below 1%, and carbon dioxide is far below 1%; therefore the alternatives represent other atmospheric proportions rather than oxygen. The word dry is important because it excludes variable water vapour from the usual composition calculation.
Which subject and chapter does this question cover?
This is a Class 11 Accountancy question. Chapter: Recording of Transactions (I & II). Topic: Covers the accounting equation.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
