Question

Which has more atoms, 6.0 g of silicon (Si:28) or 6.0 of iron (Fe:56)?

Use Avogadro's number as 6.0 x1023​

Answer 1

Answer: 6.0 g of silicon has more atoms

Step-by-step explanation:

According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number
`6.023* 10^(23)` of particles.

To calculate the moles, we use the equation:

`\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}`

a)
`\text{Number of moles of silicon}=(6.0g)/(28g/mol)=0.21moles`

1 mole of Si contains =
`6.023* 10^(23)` atoms

0.21 moles of Si contains =
`(6.023* 10^(23))/(1)* 0.21=1.26* 10^(23)` atoms

b)
`\text{Number of moles of iron}=(6.0g)/(56g/mol)=0.11moles`

1 mole of Fe contains =
`6.023* 10^(23)` atoms

0.11 moles of Fe contains =
`(6.023* 10^(23))/(1)* 0.11=0.66* 10^(23)` atoms

Thus 6.0 g of silicon has more atoms