Chemistry T9: Chemical energetics

State the characteristics of exothermic reactions

- Energy(heat) is given out to the surroundings

- Temperature of the surroundings increases

- TEC of the products is lower than the TEC of the reactant

- Enthalpy change is negative

State the characteristics of endothermic reactions

- Energy(heat) is absorbed from the surroundings

- Temperature of the surrounding decreases

- TEC of the reactants is products is higher than the TEC of the reactants

- Enthalpy change is positive

List the characteristics of bond breaking in terms of chemical energetics

- Energy is absorbed from the surroundings to break bonds

- Bond breaking is an endothermic process

- The stronger the bond, the more energy absorbed when the bond is broken

List the characteristics of bond forming in terms of chemical energetics

- Energy is released into the surroundings when bonds are formed

- Bond forming is an exothermic process

- The stronger the bond, the more energy released when the bond is formed

Use ideas about bond breaking and bond forming to explain whether a given reaction is exothermic

- Bond breaking reactions absorb energy, hence endothermic

- Bond forming reaction release energy, hence exothermic

- In an exothermic reaction, energy released into forming bonds > energy absorbed breaking bonds

Use ideas about bond breaking and bond forming to explain whether a given reaction is endothermic

- Bond breaking reactions absorb energy, hence endothermic

- Bond forming reaction release energy, hence exothermic

- In an exothermic reaction, energy released into forming bonds < energy absorbed breaking bonds

Define the term activation energy

Minimum energy a reactant particle must posses for a chemical reaction to occur