Question

The maximum number of molecules is present in (1) 15 L of water at STP (2) 15 L of H2O gas at STP (3) 15 g of ice (4) Same in all

Answer 1

(1) 15 L of water at STP has highest number of molecules.

Explanation:

The given three options are as follows:

At STP, 15 L of water; 15 L of $H_2O$; and 15 g of Ice.

If we observed, in three options $H_2O$ is present in three different states.

At standard pressure and temperature, the liquid state has maximum density hence it has high number of atoms. The density of liquid state of any compound is equal to the density of gas and solid forms at STP.

Therefore, 15 L of water will have maximum number of molecules then compared to 15 gm of ice and 15 L of $H_2O$ gas.

Answer 2

Answer:

1.15 L of water at STP

Explanation:

density of water=1 kg/lit so 15L of water with density 1kg/lit will have mass 15kg I. e 15000gram so no of moles in this case are 15000÷18=833.3mole . so no of molecules are 833.3×Na.In second case no of mole are 15÷22 .4=0.6mole.so no of molecules are 0.6×Na.In third case no of moles =15÷18=0.833mole.so no of molecules=0.833×Na.hence in first case no of molecules is maximum