Question

3. How many particles are present in 13.4 moles of carbon dioxide?

8.07. 1024 particles
04.49. 1022 particles
6.02. 1024 particles
6.02. 1023 particles

Answer 1

`\boxed {\boxed {\sf 8.07 *10^(24) \ particles}}`

Step-by-step explanation:

To convert from moles to representative particles, Avogadro's number: 6.02*10²³ is used. This number tells us the amount of particles in 1 mole of a substance. We can use it as a ratio.

`\frac {6.02*10^(23) \ particles}{1 \ mol \ CO_2}}`

Multiply by the given number of moles.

`13.4 \ mol \ CO_2 *\frac {6.02*10^(23) \ particles}{1 \ mol \ CO_2}}`

The moles of carbon dioxide will cancel out.

`13.4 *\frac {6.02*10^(23) \ particles}{1}}`

The denominator of 1 can be ignored and this becomes a simple multiplication problem.

`13.4 * {6.02*10^(23) \ particles`

`8.0668*10^(24) \ particles`

The original number of moles has 3 significant figures, so our answer must have the same. For the number we calculated, that is the hundredth place. The 6 in the thousandth place tells us round the 6 to a 7.

`8.07 *10^(24) \ particles`

13.4 moles of carbon dioxide has approximately 8.07*10²⁴ particles.