Question

How many moles are there in 5.80 X 1024 molecules of sodium sulfate, Na2SO3?

Answer 1

`\boxed {\boxed {\sf 9.63 \ mol \ Na_2SO_3}}`

Step-by-step explanation:

To convert from molecules to moles, Avogadro's Number: 6.02*10²³ must be used. This number is the amount of particles (molecules, atoms, etc.) in 1 mole of a substance. In this case, the particles are molecules of sodium sulfate. Let's create a proportion.

`( 6.022 *10^(23) \ molecules \ Na_2SO_3)/(1 \ mol \ Na_2SO_3)`

Multiply by the given number of molecules.

`5.80 *10^(24) \ molecules \ Na_2SO_3 *( 6.022 *10^(23) \ molecules \ Na_2SO_3)/(1 \ mol \ Na_2SO_3)`

Flip the fraction so the molecules of sodium sulfate cancel.

`5.80 *10^(24) \ molecules \ Na_2SO_3 *( 1 \ mol \ Na_2SO_3)/(6.022 *10^(23) \ molecules \ Na_2SO_3)`

`5.80 *10^(24) *( 1 \ mol \ Na_2SO_3)/(6.022 *10^(23))`

`( 5.80 *10^(24) \ mol \ Na_2SO_3)/(6.022 *10^(23))`

Divide.

`9.63135171 \ mol \ Na_2SO_3`

The original measurement has 3 significant figures (5, 8, and 0), so our answer must have the same.

For the number we calculated that is the hundredth place. The 1 in the thousandth place tells us to leave the 3.

`9.63 \ mol \ Na_2SO_3`

There are about 9.63 moles of sodium sulfate