Question

What is the total sample size (in grams) for a sample of magensium nitrite which contains 1.09 g of oxygen?

Answer 1

Mg(NO3)2
1 molucule of Mg(NO3)2 contains 6 atoms Of Oxygen
1 mole of Mg(NO3)2 contains 6 moles Of Oxygen

1mole of Mg(NO3)2 is 24+2*(14+3*16)=148 gr
6 mole of atoms of oxygen is 6*16=96gr
so

148 gr of Mg(NO3)2 contains 96gr Of Oxygen
x=? 1.09

Answer 2

Hi! Do you actually mean magnesium nitrite, or is your problem about magnesium nitrAte?

Answer 3

i mean magnesium nitrite

Answer 4

I'm always a fan of starting off with a balanced chemical equation

Answer 5

@zbay: there is no reaction involved in this problem.
@ktrigga: mos1635's method is correct, but the nitrite ion's formula is\[(NO _{2})^{-}\] , so there are only 2 atoms of oxygen and not 3.

Answer 6

Mg(NO4)2
1 molucule of Mg(NO2)2 contains 4 atoms Of Oxygen
1 mole of Mg(NO2)2 contains 4 moles Of Oxygen
1mole of Mg(NO2)2 is 24+2*(14+2*16)=124 gr
4 mole of atoms of oxygen is 4*16=64gr
so
124gr of Mg(NO3)2 contains 96gr Of Oxygen
x=? 1.09

thanks @Vincent-Lyon.Fr