09 Chemical Energetics

What is activation energy

The minimum amount of energy that colliding particles must posses to react with each other

What are exapmle of endothermic reactions

Thermal decomposition, dissolving of some ionic compounds in water, action of light on silver bromide in photo graphic film

What are exapmle of exothermic reactions

Combustion of fuel, respiration, neutralisation

Explain why the reaction is endothermic.

More energyvid absorbed when - moles of - bonds and - bonds are broken as compared to the energy released when - and - moles of - and - bonds are formed. This will results in an endothermic reaction where the temperature of the surroundingd with decrease.

Suggest how the experimental enthaloy change might be different from the theoretical value.

The experimental enthalpy change will be less positive/negative than the actual value as heat may be lost to the surroundings and not used to heat up the water.

What is exothermic

More energy is released in the formation of new bonds than consumed by the breaking of old bonds

What is endothermic

More energy is consumed in the breaking of old bonds than released during the formation of new bonds

What is bond energy

The amount of energy absorbed to break one mole of a chrmical bond

What is the photosynthesis reaction

glucose + oxygen —> water + carbon dioxide

Is respiration endothermic or exothermic

Exothermic

Is photosynthesis endothermic or exothermic

Endothermic