Energy And Rate Test

Question 1

Define endothermic

Answer 1

• Takes in heat from surroundings
• Temp. of surroundings decrease
• Energy needed to break old bond is > than energy released from forming new bonds
• 🔺H is positive

Question 2

Define exothermic

Answer 2

• Releases heat energy to the surroundings
• Temp. of surroundings increase
• Energy released from forming new bonds is > than the energy needed to break old bonds
• 🔺H is negative

Question 3

Define Enthalpy

Answer 3

Total energy (or enthalpy) of a system is total of the chemical energy stored in bonds & the kinetic energy of the substance.

Question 4

Define activation energy

Answer 4

Minimum energy required for a reaction to occur when energy of collision is equal or greater than the activation energy.

Question 5

Define transition state and graph to show where it is

Answer 5

The point in which the particles have the greatest amount of energy.

Question 6

State the law of conservation of energy

Answer 6

• Energy can’t be created if destroyed, only transferred.

- All energy lost or gained must come or go somewhere.

Question 7

Define catalyst

Answer 7

A substance that is added to a reaction but isn’t used up in a reaction, it provides an alternative pathway with lower activation energy.

Question 8

Draw a Maxwell-Boltzmann distribution to show the distribution of energy of particles at two different temperatures. Clearly identify which curve is for the higher temperature.

Answer 8

(Refer to book and see the diagram)