energetics

Question 1

what is an exothermic reaction

Answer 1

reaction which gives out energy in the form of heat usually shown by rising temperature of the surroundings

Question 2

what is an endothermic reaction

Answer 2

a reaction that takes in energy from the surroundings in the form of heat, usually shown by fall in temperature of the surroundings

Question 3

how can you find out enthalpy change

Answer 3

using a calorimetry

Question 4

what does calorimetry do

Answer 4

allows you to measure the amount of energy transferred in a chemical reaction

Question 5

how do you measure the amount of energy transferred in dissolving displacement and neutralization reactions

Answer 5

1. take the temperature of reactants
2. mix them
3. measure the temperature of the solution at the end of the reaction

Question 6

in order to investigate the enthalpy change of dissolving, displacement or neutralization reactions, what do you use?

Answer 6

polystyrene cup

Question 7

how do you reduce the amount of energy lost to the surroundings in an enthalpy change investigation

Answer 7

give the polystyrene cup more insulation by putting it in a beaker of cotton wool and putting a lid on the cup to reduce energy loss by evaporation

Question 8

name the biggest problem with energy measurements

Answer 8

amount of energy loss to the surroundings

Question 9

how do you measure the amount of energy transferred when a full is burned

Answer 9

burn the fuel and use the flame to heat up some water. use a copper container as copper conduct heat well

Question 10

what can you do to make the calorimetry combustion experiment as accurate as possible

Answer 10

reduce drafts by using a screen