Question

How many moles of potassium oxide will be formed when 1.52 moles of potassium reacts with oxygen according to the following equation:

4K + O2 -> 2K2O

Answer 1

the balanced equation for formation of potassium oxide is as follows

4K + O₂ --> 2K₂O

molar ratio of K to K₂O is 4:2

when 4 mol of potassium reacts, 2 mol of potassium oxide is formed

when 4 mol of K reacts - 2 mol of K₂O

when 1.52 mol of K reacts - 2/4 x 1.52 = 0.76 mol of K₂O

0.76 mol of K₂O is formed

Answer 2

0.76 mol.

Step-by-step explanation:

• From the balanced equation: 4K + O₂ → 2K₂O,

• It is clear that 4.0 moles of K react with 1.0 mole of oxygen to produce 2.0 moles of K₂O.

• We can use cross multiplication to get the no. of moles of potassium oxide will be formed when 1.52 moles of potassium reacts with oxygen:

4.0 moles of K will produce → 2.0 moles of K₂O.

1.52 moles of K will produce → ??? moles of K₂O.

∴ The no. of moles of potassium oxide will be formed when 1.52 moles of potassium reacts with oxygen = (1.52 mol)(2.0 mol)/(4.0 mol) = 0.76 mol.