Question

Enter a balanced chemical equation for the reaction between potassium metal and liquid water.

Answer 1

• 2K (s) + 2H₂O (l) → 2KOH (aq) + H₂(g)↑

Step-by-step explanation:

1) Word equation (given)

• Potassium + water → ?

2) Kind of reaction

• Potassium is an alkali metal.

This is a single replacement reaction.

Alkali metals is the group of metals in the group 1 of the periodic table. These are the most active metals, meaning that they react violently with water releasing hydrogen gas.

• Alkali metals can lose an electron to form compounds with oxidation number +1.

• The general equation for the reaction of an alkali metal and water is:

Metal + Water → hydroxide + gaseous hydrogen

X + H₂O → XOH(aq) + H₂ (g) ↑

3) Chemical equation

• K (s) + H₂O (l) → KOH(aq) + H₂(g)↑

4) Balance

• 2K (s) + 2H₂O (l) → 2KOH(aq) + H₂(g)↑

There is the same number of each atom on both sides: 2 K in the left and in the right, 4 H in the left and in the right, and 2 oxygen in the left and in the right. So, the equation is balanced.