Connie and Dewayne know that solid potassium

Question

reacts very strongly with water, producing a chemical
called potassium hydroxide along with hydrogen gas.
They know the chemical equation looks like this.
2K + 2H O → 2KOH + some amount of H
a. There are 4 atoms of hydrogen shown on the
reactant side. How many total atoms of hydrogen
must be on the product side?
(1 point)
A-2
B-4
C-6
D-8

Answer 1

In the given chemical equation:

\[ 2K + 2H_2O \rightarrow 2KOH + \text{some amount of } H_2 \]

On the reactant side, there are a total of 4 hydrogen atoms from the water (2 from each water molecule, and there are 2 water molecules: 2 \(\times\) 2 = 4).

In the products, we have:

• 2 potassium hydroxide (KOH) which contains 1 hydrogen atom each, contributing 2 hydrogen atoms (2 KOH \(\rightarrow\) 2 H).
• "Some amount of H" which we assume represents hydrogen gas, H₂.

To balance the hydrogen atoms, if we have 4 hydrogen atoms on the reactant side, we need to have the same total on the product side.

From 2 KOH, we have 2 hydrogen atoms, so we need 2 more from the hydrogen gas:

• 2 from KOH + 2 from H₂ = 4 total hydrogen atoms on the product side.

Thus, the correct answer is:

B-4