Question

Calculate the no. of moles of water present in its 504 mL sample at STP.​

Answer 1

Given:

(i) The volume of the water sample is 504 ml.

To find:

(i) The number of moles present in the water sample.

Solution:

We know that 1 mole of any substance is equal to 6.023*10²³ molecules and 22.4L is the volume occupied by 1 mole of the chemical substance at STP.

So,

22.4 L (22400ml) is the volume occupied by 1 mole of the sample.

By unitary method, 1 ml would be the volume occupied by (1/22400) moles of the sample.

So, 504 ml is the volume occupied by (504/22400) moles

= 0.0225 moles.

The sample has 0.0225 moles.