Question

2. 7.5 g of potassium react with water to produce potassium hydroxide and hydrogen gas. Calculate the mass of potassium hydroxide produced. (8 points)

Answer 1

Answer:

10.7 g of KOH

Explanation:

First of all, we determine the reaction:

2K (s) + 2H₂O(l) → H₂(g) + 2KOH(aq)

We convert the mass of K, to moles → 7.5 g . mol/39.1 g = 0.192 moles

Ratio is 2:2, so the moles I have of K must produce the same moles of KOH. In this case, the produces moles of KOH are 0.192 moles.

We convert the moles to mass, to finish the answer:

0.192 mol . 56.1g /1mol = 10.7 g of KOH