Question

How many molecules are contained in each of the following (scientific Notation)

2.66 mol S8

0.799 mol NH3

10.5 g of C2H5OH

1292 g of Cl2

Answer 1

We know that 1 mole of any molecule contains Avogadros number of molecules

Avogadros Number = 6.023 x 10²³

So

1)

2.66 mol S₈ = 2.66 x 6.023 x 10²³ = 1.60 x 10²⁴ molecules

2)

0.799 mol NH₃ = 0.799 x 6.023 x 10²³ = 4.812 x 10²³ molecules

3)

10.5 g of C₂H₅OH

We know Mol = mass / molar mass

So mole of C₂H₅OH = 10.5 g/46.07 g/mol = 0.228 moles

0.228 mole = 0.228 x 6.023 x 10²³ = 1.373 x 10²³ molecules

4)

1292 g of Cl₂

So moles of Cl₂ = mass of Cl₂ /molar mass of Cl₂

= 1292 g / 35.45 g/mol

= 36.45 mol

36.45 mol = 36.45 x  6.023 x 10²³ = 2.19 x 10²⁵ molecules