Question

Calculate the mass of 100 molecules of Sucrose(C12H22O11).

Answer 1

Answer : The mass of 100 molecule of sucrose is $56.8106\times 10^{-21}g$.

Solution : Given,

Molar mass of carbon = 12 g/mole

Molar mass of hydrogen = 1 g/mole

Molar mass of oxygen = 16 g/mole

The formula chemical formula of sucrose is $C_{12}H_{22}O_{11}$.

First we have to calculate the Molar mass of the sucrose.

Molar mass of sucrose = $(12\times 12g/mole)+(22\times 1g/mole)+(11\times 16g/mole)=342g/mole$

Now we have to calculate the number of molecules in one mole of a substance, divide the molar mass of sucrose by the Avogadro's number.

The value of Avogadro's number is $6.02\times 10^{23}molecule/mole$.

One molecule of sucrose mass = $\frac{\text{ Molar mass of sucrose}}{\text{ Avogadro's number}}=\frac{342g/mole}{6.02\times 10^{23}molecule/mole}=56.8106\times 10^{-23}g$

and 100 molecule of sucrose mass = one molecule of sucrose × 100 = $56.8106\times 10^{-23}g\times 100=56.8106\times 10^{-21}g$

Therefore, the mass of 100 molecule of sucrose is $56.8106\times 10^{-21}g$.

Answer 2

Answer:

Molar mass of carbon = 12 g/mole

Molar mass of hydrogen = 1 g/mole

Molar mass of oxygen = 16 g/mole

The formula chemical formula of sucrose is C_{12}H_{22}O_{11}C

12

H

22

O

11

.

First we have to calculate the Molar mass of the sucrose.

Molar mass of sucrose = (12\times 12g/mole)+(22\times 1g/mole)+(11\times 16g/mole)=342g/mole(12×12g/mole)+(22×1g/mole)+(11×16g/mole)=342g/mole

Now we have to calculate the number of molecules in one mole of a substance, divide the molar mass of sucrose by the Avogadro's number.

The value of Avogadro's number is 6.02\times 10^{23}molecule/mole6.02×10

23

molecule/mole .

One molecule of sucrose mass = \frac{\text{ Molar mass of sucrose}}{\text{ Avogadro's number}}=\frac{342g/mole}{6.02\times 10^{23}molecule/mole}=56.8106\times 10^{-23}g

Avogadro’s number

Molar mass of sucrose

=

6.02×10

23

molecule/mole

342g/mole

=56.8106×10

−23

g

and 100 molecule of sucrose mass = one molecule of sucrose × 100 = 56.8106\times 10^{-23}g\times 100=56.8106\times 10^{-21}g56.8106×10

−23

g×100=56.8106×10

−21

g

Therefore, the mass of 100 molecule of sucrose is 56.8106\times 10^{-21}g56.8106×10

−21

g .