Question

Calculate the mass in grams of 3.94×1024 molecules of formaldehyde. The chemical formula for formaldehyde is CH2O.

Answer 1

CH20 = 30.031/mol
30.031 X 1024 = 30751.744
30751.744 X 3.94 = 121161.87136

Your answer: 121161.87136

Answer 2

Mass in grams of formaldehyde = 196.51 g

Step-by-step explanation:

No. of molecules of formaldehyde =
`3.94 * 10^(24)`

Moles is related with number of molecules as:

`mol=(No.\ of\ molecules)/(Avogadro's\ no.)`

Avogadro's no. =
`6.02 * 10^(23)`

moles of formaldehyde

`=(3.94* 10^(24))/(6.02* 10^(23)) \\=6.544\ mol`

Molar mass of formaldehyde = 30.03 g/mol

Molar mass is related with mass as:

Mass = Moles × Molar mass

= 6.544 × 30.03

= 196.51 g