Question

how many molecules of O2 are present in 1 L air containing 80% volume of O2 at STP

Answer 1

Answer:

Answer: 2.15x 10^22 molecules.

Explanation:

▪️ Correct question should be: how many molecules of oxygen are present in 1 litre of air containing 80% of O2.

First, we will have to find amount of energy in one oxygen.

Therefore,

➡️ Amount of oxygen present in 1 litre air is = 80% *1000 ml

➡️ (80/100)*1000

=800ml

▪️ We know that, 1 mole of STp occupies 22.4 litre

It is equal to = 22400ml of O2 gas contains 6.022x 10^23 molecules

So,

➡️ 1ml of O2 gas Contains =6.022x10^23/22400

According to question, we have to find 800ml molecules.

Therefore,

800ml contains =(6.022x 10^23/22400) *800

=> 2.15 x 10^22

▪️ Hence, molecules present in 1 litre air containing 80% volume of at STP is 2.15x 10^22 molecules.

Answer 2

2.15×10²² molecules are the ideal answer.

Explanation:

• The amount of oxygen in 1 liter air is 80% (1000ml) = 80ml.
• one mole of any gas at STP occupies 22.4 liters.
• And 22400 ml of O₂ gas includes 6.022×10²³ molecules.
• one ml of oxygen gas includes = 6.022×10²³/22400 ×800 ml includes = 6.022×10²³/22400 × 800 = 2.15×10²² molecules.

The molecules found in 1 liter air containing 80% extent at STP is 2.15×10²² molecules.

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