How many moles of Mg are needed to react w 16.0g of O2?

Question

I have the equation 2Mg + O2 --> 2MgO.. how do I solve this???/

Answer 1

16 g O2 / 32 g O2 = .5 mol O2

balanced equation says ratio of 2:1 for Mg:O2

that means twice as much Mg as O2

2 x .5 mol = 1 mol Mg

mass of Mg is 24.3, so 24.3 g Mg = 1 mol Mg

Answer 2

Hi there,

first, find the number of moles of O2, (16/32)= 0.5 mol
Then look at the stoichiometric equation whereby,
2 moles of Mg require to react with 1 mole of O2.
Therefore,
1 mole of Mg is require to react with 0.5 mole of O2.

Hope that helps.

Answer 3

This is how you work it out,

First work out how many moles 16g of O2 is(remember O2 not O),

So take the the M weight of oxygen 15.99 or 16 grames per mole
16 X2 = 32g/mole (O2 not O) divide 32g/16g = 0.5 moles
2Mg + 02 --> 2Mg0
look at the ratio's of oxygen to Mg and that yours answer. There are 0.5moles to 16g of O2
And the ratio is
2:1 or so if there are 0.5 moles of oxygen then there are 1.0 moles of Mg needed.

Answer 4

2Mg + O2 --> 2MgO

the moles of O2 16/32 = 0.5 moles
the moles of Mg = 0.5 * 2/1 = 1 mole