Question

How many water molecules are in a bottle of water that contains 500. mL? The density of water is 1.0 g/mL .

Answer 1

$m= D*V$

1) 500*1.0=500 g

$n= m/M$

2) n(H2O)= 500/(16+2)= 27,8 mole

$N=n*Na$

Na= 6,02*10^(23)

3) N= 27,8*6.02*10^(23) = 1.67356e+25