Answers:
0.606 g H₂
Step-by-step explanation:
We know we will need a balanced equation with masses and molar masses, so let’s gather all the information in one place.
M_r: 39.10 2.016
2K + 2H₂O ⟶ 2KOH + H₂
m/g: 23.5
(a) Calculate the moles of K
n = 23.5 g K × 1 mol K /39.10 g K
n = 0.6010 mol K
(b) Calculate the moles of H₂
The molar ratio is (1 mol H₂/2 mol K)
n = 0.6010 mol K × (1 mol H₂/2 mol K)
n = 0.3005 mol H₂
(c) Calculate the mass of H₂
m = 0.3005 mol H₂ × (2.016 g H₂/1 mol H₂)
m = 0.606 g H₂
