Question

Determine the number of ch2cl2 molecules in 25.0 g ch2cl2.determine the number of ch2cl2 molecules in 25.0 g ch2cl2.

Answer 1

Answer : The number of molecules of
`CH_2Cl_2` are,
`1.77*10^(23)`

Explanation : Given,

Mass of
`CH_2Cl_2` = 25 g

Molar mass of
`CH_2Cl_2` = 85 g/mole

First we have to calculate the moles of
`CH_2Cl_2`.

`\text{Moles of }CH_2Cl_2=\frac{\text{Mass of }CH_2Cl_2}{\text{Molar mass of }CH_2Cl_2}=(25g)/(85g/mole)=0.294moles`

Now we have to calculate the number of molecules of
`CH_2Cl_2`.

As, 1 mole of
`CH_2Cl_2` contains
`6.022* 10^(23)` number of molecules of
`CH_2Cl_2`

So, 0.294 mole of
`CH_2Cl_2` contains
`0.294* 6.022* 10^(23)=1.77*10^(23)` number of molecules of
`CH_2Cl_2`

Therefore, the number of molecules of
`CH_2Cl_2` are,
`1.77*10^(23)`

Answer 2

Answer is: there is 1,77·10²³ molecules of CH₂Cl₂.
m(CH₂Cl₂) = 25 g.
n(CH₂Cl₂) = m(CH₂Cl₂) ÷ M(CH₂Cl₂).
n(CH₂Cl₂) = 25 g ÷ 85 g/mol.
n(CH₂Cl₂) = 0,294 mol.
N(CH₂Cl₂) = n(CH₂Cl₂) · Na.
N(CH₂Cl₂) = 0,294 mol · 6,023 1/mol.
N(CH₂Cl₂) = 1,77·10²³.
n - amount of substance.
Na - Avogadro number.