If a given forward reaction is exothermic and the reactants and products in a flask initially are at equilibrium, what will happen when the temperature is raised?

A. The system will shift to the right (in the direction of the forward reaction).

B. The system will shift to the left (in the direction of the reverse reaction).

C. The system will not shift.

D. The rates of both the forward and reverse reactions immediately decrease.

B. The system would shift  to the left ( in the direction of the reverse reaction).

Explanation:

Since the reaction system is exothermic (meaning it releases heat during the process), increasing the temperature will shift the equilibrium to the left, according to Le Charteliers's Principle so as to annul the effect of the contraint (heat) added to the system.

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.