chemistry C6

Question 1

What needs to happen for substances to react in both endothermic and exothermic reactions?

Answer 1

For substances to react, the molecules need to be broken down, so therefore, the new bonds (products) are formed.

Question 2

exothermic reactions=

temperature…….

Answer 2

In exothermic reactions, if difference in temperature is given out as heat, the temperature goes up.

Question 3

When do exothermic reactions occur?

Answer 3

Exothermic reactions occur when the bonds in the reactants have more energy than the bonds in the products.

Question 4

endothermic reactions=

temperature…..

Answer 4

In endotehrmic reactions, temperature goes down.

Extra energy is need from and it is taken from the surroundings so the temperature falls.

Question 5

When do endothermic reactions occur?

Answer 5

Endothermic reactions occur when the bonds in the reactants have less energy that the bonds in the products.

Question 6

Example of physical process (endothermic)

Answer 6

When ice cubes absorb heat energy from the surroundings, they melt and form water (liquid). In this process no chemical bonds are broken or formed.