Question

What mass of Magnesium oxide will be formed when 12g of Mg is burned in air?( Ar of Mg=24, O = 16)
2Mg (s) + O2(g) = 2MgO (s)

Answer 1

Answer:

Mg + 1/2 O2 → MgO

1 mol = 24 g of Mg

X mol = 12 g of Mg

x = 0.5 moles of Mg

Mg :MgO = 1:1 (coefficient from equations using mole ratio)

So

0.5 moles of MgO

1 mol MgO = (24+16) g = 40 g

0.5 moles of MgO = 0.5 × 40

= 20 g of MgO produced

Answer 2

Answer:

x=20g

Explanation: