Question

According to the reaction below, how many grams of KCl (potassium chloride) can be formed from 70.90 g of chlorine with excess potassium?

2K + Cl2 ---> 2 KCl

Answer 1

149.1 g KCl

Step-by-step explanation:

2 K + Cl₂ ⇒ 2 KCl

This is your chemical equation. Use this equation to figure out the stoichiometry between Cl₂ and KCl. According to the equation, for every 2 moles of KCl, you need 1 mole of Cl₂, making the ratio between KCl and Cl₂ 2/1.

First, convert grams of Cl₂ to moles of Cl₂. The molar mass is 70.906 g/mol.

(70.90 g Cl₂)/(70.906 g/mol) = 0.9999 mol Cl₂

Convert moles of Cl₂ to moles of KCl using the stoichiometric relationship.

(0.9999 mol Cl₂) × (2 mol KCl/1 mol Cl₂) = 1.9998 mol KCl

Convert moles of KCl to grams of KCl. The molar mass is 74.55 g/mol.

(1.998 mol KCl) × (74.55 g/mol KCl) = 149.1 g KCl

You will produce 149.1 g KCl.