Question

Calculate the number of moles in each of the following masses: a) 64.1 g of amuminum
B)28.1 g of silicon
C) 0.255 g of sulfur

Answer 1

Answer:

moles of Si= 28.1/28

ans ~1mole

moles of sulphur 0.255/32=

Answer 2

(a) 2.37 moles of Aluminium

(b) 1 moles of Silicon

(c) 0.0079 moles of sulfur

To calculate the number of moles we can use

Moles = given weight / Molecular weight

(a) Given weight of Aluminium = 64.1 g

Molecular weight of Aluminium = 27 g

Moles = given weight / molecular weight = 64.1/27 = 2.37 moles

(b) Given weight of Silicon = 28.1 g

Molecular weight of Silicon = 28.1 g

Moles = given weight / molecular weight = 28.1/28.1 = 1 moles

(c) Given weight of Sulfur = 0.255 g

Molecular weight of Sulfur = 32 g

Moles = given weight / molecular weight = 0.255/32 = 0.0079 moles