In which case is the number of molecules of water maximum?

Options

A. 18 mL of water
B. 0.18 g of water
C. 0.00224 L of water vapour at 1 atm and 273 K
D. `10^(-3)` mol of water

Answer

A

Explanation

`"18 mL of water = 18 g "=(18)/(18)" mol = 1 mol"`
`" "(because" density of water = 1 g mL"^(-1))`
`"0.18 g of water "=(0.18)/(18)"mol = 0.01 mol"`
`"0.00224 L of water vapour"=(0.00224)/(22.4)"mol"`
`=0.0001 mol`
`10^(-3)" mol of water "=0.001mol`
Thus, 18 mL of water has maximum moles and hence maximum number of molecules.