Question

How many water molecules are in a block of ice containing 2.25 mol of water (H2O)?

Answer 1

Answer: $13.5\times 10^{23}$ molecules

Explanation:

According to avogadro's law, 1 mole of every substance occupies 22.4 Liters at STP and contains avogadro's number $6.023\times 10^{23}$ of particles.

Now 1 mole of $H_2O$ molecule contains = $6.023\times 10^{23}$ of molecules.

2.25 mole of $H_2O$ molecule contains= $\frac{6.023\times 10^{23}}{1}\times 2.25=13.5\times 10^{23}$ molecules.

$13.5\times 10^{23}$ molecules are there in 2.25 moles of water.

Answer 2

2.25 moles of water ---> ? molecules of water

For this you have to use Avogadro's Number which is 6.022×10²³ molecules

$\frac{2.25 moles}{} * \frac{6.022x10 x^{23} }{1 mol} = 1.35495x10 x^{24}$