Question

1) A 10g sample of H2(g) reacts with a 22g sample of O2(g) according to

the equation: _H2(3)+ -_02(3)→ _H,0(1)

Which reactant is limiting? Which is in excess?

Answer 1

H₂ is excess reactant and O₂ the limiting reactant

Step-by-step explanation:

Based on the chemical reaction:

2H₂(g) + O₂(g) → 2H₂O

2 moles of H₂ react per mole of O₂

To find limiting reactant we need to convert the mass of each reactant to moles:

Moles H₂ -Molar mass: 2.016g/mol-:

10g H₂ * (1mol / 2.016g) = 4.96 moles

Moles O₂ -Molar mass: 32g/mol-:

22g O₂ * (1mol / 32g) = 0.69 moles

For a complete reaction of 0.69 moles of O₂ are needed:

0.69mol O₂ * (2mol H₂ / 1mol O₂) = 1.38 moles of H₂

As there are 4.96 moles,

H₂ is excess reactant and O₂ the limiting reactant