Take this Quiz: GCSE Chemistry: Energy Changes | Zestly

Question 1

Which of the following statements correctly describes the energy change in an exothermic reaction?

Accepted Answer

Energy is transferred from the chemical system to the surroundings, causing the temperature to rise.

Question 2

What is the definition of activation energy in a chemical reaction?

Accepted Answer

The minimum amount of energy particles must collide with to react.

Question 3

In a reaction profile diagram for an endothermic reaction, how does the energy level of the products compare to the reactants?

Accepted Answer

The products are at a higher energy level than the reactants.

Question 4

Consider the reaction: $	ext{H}_2 + 	ext{Cl}_2 ightarrow 2	ext{HCl}$. Given the bond energies: $	ext{H-H} = 436 	ext{ kJ/mol}$, $	ext{Cl-Cl} = 242 	ext{ kJ/mol}$, and $	ext{H-Cl} = 431 	ext{ kJ/mol}$. Calculate the overall energy change.

Answer

$+184 	ext{ kJ/mol}$

Answer

$-184 	ext{ kJ/mol}$

Answer

$+248 	ext{ kJ/mol}$

Answer

$-248 	ext{ kJ/mol}$

Question 5

Which of the following are true regarding the breaking and making of chemical bonds?

Answer

Breaking bonds is an endothermic process.

Answer

Breaking bonds is an exothermic process.

Answer

Making bonds is an exothermic process.

Answer

Making bonds is an endothermic process.