Question

What is the mass of 5 mole of ammonia . Calculate the number of NH₃ molecules, nitrogen atom and hydrogen atoms in it..

Answer 1

Molar mass of NH_3

`\\ \sf\longmapsto 14u+3(1u)`

`\\ \sf\longmapsto 14u+3u`

`\\ \sf\longmapsto 17g/mol`

We know.

No of moles=Given mass/Molar mass

`\\ \sf\longmapsto Given\;Mass=17(5)`

`\\ \sf\longmapsto Given \:Mass\:of\:NH_3=85g`

Now

Lets write the balanced equation

`\\ \sf\longmapsto N_2+3H_2=2NH_3`

• There is 2moles of Ammonia
• 3moles of H_2
• 1mole of N_2

Now

`\boxed{\sf No\:of\:Molecules =No\:of\;moles* Avagadro\:no}`

For Hydrogen

`\\ \sf\longmapsto 3* 6.023* 10^(23)`

`\\ \sf\longmapsto 18.069* 10^(23)`

`\\ \sf\longmapsto 1.8* 10^(22)molecules`

For Ammonia

`\\ \sf\longmapsto 2* 6.023* 10^(23)`

`\\ \sf\longmapsto 12.046* 10^(23)`

`\\ \sf\longmapsto 1.2* 10^(22)molecules`

For Nitrogen

`\\ \sf\longmapsto 1* 6.023* 10^(23)`

`\\ \sf\longmapsto 6.023* 10^(23)molecules`