Endothermic And Exothermic Reactions

Question 0

Endothermic reaction

Answer 0

When more heat is absorbed from the surroundings and the temperature of the reaction mixture decreases when more energy is taken in than it releases.

Question 1

Exothermic reaction

Answer 1

When more energy is released than absorbed when the reaction takes place.

Question 2

Activation energy

Answer 2

• The minimum energy the colliding molecules must have before a reaction can take place…
• Energy required to break the bonds in the reacting substance to form the activated complex

Question 3

Activated complex

Answer 3

Is the temporary unstable linking of atoms, representing a high energy formed in the the process of the reactants being changed to products.

Question 4

Why is the activation complex temporary?

Answer 4

Because atoms strive to obtain the lowest potential energy possible.

Question 5

Bond energy

Answer 5

The energy that is absorbed to break an existing bond, or the energy that is released when a bond is formed.

Question 6

Bond length

Answer 6

The amount of energy released when a bond is formed or the amount of energy required to break a bond.

Question 7

Enthalpy

Answer 7

The total amount of chemical potential energy in a chemical system..

Question 8

What is the equation for enthalpy?

Answer 8

Enthalpy= E(product) - E(reactants)

= E(absorbed) + E(-released)

Question 9

Catalyst

Answer 9

A substance that changes/increases he rate of a reaction without itself undergoing any permanent changes or being used up.