Topic 5 Bond energies

Question 1

Whag happens to bonds during a chemical reaction

Answer 1

Old bonds are broken and new bonds are formed

Question 2

What type of reaction is bond breaking

Answer 2

Endothermic process as energy must be supplied to break the existing binds

Question 3

What type of reaction is bond formation

Answer 3

Exothermic process as energy is released when new bonds are formed

Question 4

In an exothermic reaction what is greater, the energy released by forming bonds or the energy released to make them

Answer 4

The energy released by forming bonds

Question 5

In an endothermic reaction what is greater, the energy released by forming bonds or the energy released to make them

Answer 5

The energy used to break the bonds

Question 6

Overall energy change equation

Answer 6

Overall energy change = sum of all energies needed to break bonds in the reactants - the energy released when the new bonds are formed in the products

Question 7

You can’t compare the overall changes of reactions unless you know ….

Answer 7

The exact numerical differences in bind energies