Question

How many formula units are contained in 23.5 g of Sb2S3

Answer 1

Answer: The number of formula units in given amount of
`Sb_2S_3` are
`4.155* 10^(22)`

Step-by-step explanation:

To calculate the number of moles, we use the equation:

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

Given mass of
`Sb_2S_3` = 23.5 g

Molar mass of
`Sb_2S_3` = 339.7 g/mol

Putting values in above equation, we get:

`\text{Moles of }Sb_2S_3=(23.5g)/(339.7g/mol)=0.069mol`

According to mole concept:

1 mole of a compound contains
`6.022* 10^(23)` number of formula units

So, 0.069 moles of
`Sb_2S_3` will contain =
`(0.069* 6.022* 10^(23))=4.155* 10^(22)` number of formula units

Hence, the number of formula units in given amount of
`Sb_2S_3` are
`4.155* 10^(22)`

Answer 2

The molar mass of Sb2S3 is approximately equal to 339.7 g/mol. We calculate the number of moles of Sb2S3 by dividing the given mass by the molar mass.
n = 23.5 g / (339.7 g/mol)
n = 0.0692 mols
To calculate for the number of formula units, we multiply the number of mols by the Avogadro's number,
number of formula units = (0.0692 mols)(6.022 x 10^3)
= 4.167 x 10^22 formula units