the reaction shifts left or toward the reactants when hcl is added. which substance(s) increase in…

the reaction shifts left or toward the reactants when hcl is added. which substance(s) increase in concentration during the shift? h₂(g) + cl₂(g) ⇌ 2hcl(g) + 184.6 j h₂ and cl₂ hcl
Answer
Explanation:
Step1: Analyze Le Chatelier's Principle
When a stress (like adding a product) is applied to an equilibrium system, the system shifts to counteract the stress. Here, adding HCl (a product) shifts the reaction left (toward reactants).
Step2: Determine Concentration Changes
A left shift means reactants ($\ce{H2}$ and $\ce{Cl2}$) are formed from products ($\ce{HCl}$). So their concentrations increase, while $\ce{HCl}$ concentration decreases.
Answer:
$\ce{H2}$ and $\ce{Cl2}$