Question

Find the empirical formula for

42.05g of nitrogen, 95.95 of oxygen

and
7.33g of lanthanum, 2.96g of oxygen

Answer 1

`NO_2` and
`La_2O_7`

Step-by-step explanation:

Nitrogen:

`(42.05)/(14)=3`

Oxygen:

`(95.95)/(16)=6`

Ratio:

`3:6=1:2`

So empirical formula becomes
`NO_2`

-----

Lanthanum:

`(7.33)/(139)=0.0527`

Oxygen:

`(2.96)/(16)=0.185`

Ratio:

`0.0527:0.185=1:3.5=2:7`

So empirical formula becomes
`La_2O_7`