Question

How many moles of S are in each of the following quantities?

Part A 22 g of S Express your answer using two significant figures. nothing   mole   SubmitRequest Answer Part B 126 g of SO2 nothing   moles   SubmitRequest Answer Part C 3.0 moles of Al2S3 Express your answer using two significant figures. nothing   moles   SubmitRequest Answer

Answer 1

A)

Molar mass of S = 32.07 g/mol

mass(S)= 22 g

use:

number of mol of S,

n = mass of S/molar mass of S

=(22 g)/(32.07 g/mol)

= 0.686 mol

Answer: 0.69 mol

B)

Molar mass of SO2,

MM = 1*MM(S) + 2*MM(O)

= 1*32.07 + 2*16.0

= 64.07 g/mol

mass(SO2)= 126 g

use:

number of mol of SO2,

n = mass of SO2/molar mass of SO2

=(1.26*10^2 g)/(64.07 g/mol)

= 1.967 mol

This is number of moles of SO2

one mole of SO2 contains 1 moles of S

use:

number of moles of S = 1 * number of moles of SO2

= 1 * 1.967

= 1.967

Answer: 1.97 moles

C)

one mole of Al2S3 contains 3 mole of S

use:

number of moles of S = 3 * number of moles of Al2S3

= 3 * 3.0

= 9.0

Answer: 9.0 moles