Answer to Question #136488 in General Chemistry for Javier

Question

If you have 15.0 g Na, how many grams of O2 are required for reaction?

Answer 1

Let's

consider the reaction that occurs between Na(s) and O₂(g) is...

4Na(s) + O₂(g) ------> 2Na₂O

Atomic mass of Na = 23 g/mol

Molicular mass of Oxygen (O₂) = 32 g/mole

In the above reaction

4 moles of Na reacts with 1 mole of molicular Oxygen (O₂)

1 mole of Na = 23 g Na

4 mole of Na = (4×23) g Na

= 92 g Na

So,

92 g Na reacts with 32 g of O₂

1 g Na reacts with (32 g/92 g) O₂

So,

15 g Na reacts with [(32 g/92 g) × 15 g] O₂ molicule

= 5.217 g O₂ molicule

(Upto three significant decimal)

Hence,

5.217 grams of O₂ are required to react with 15 g of Na