energetics ✓ Flashcards
1
Q
what is it called when a chemical reaction gives out heat energy ?
A
exothermic
2
Q
what is it called when a chemical reaction takes in heat energy ?
A
endothermic
3
Q
what is a neutralisation experiment ?
A
- get clamp stand with polystyrene cup with sodium hydroxide and a thermometer in it
4
Q
what is a combustion reaction ?
A
- set up clamp stand, a beaker, and a spirit burner with ethanol in
- weigh ethanol and spirit burner before reaction and after reaction
- measure start and end temperature of water
- beaker has water in
5
Q
what is a displacement reaction ?
A
- get clamp stand, a beaker with a polystyrene cup in it with hydrochloric acid inside and a thermometer
- put magnesium in the hydrochloric acid
- find out how much magnesium caused hydrochloric acid to rise in temperature and how much
6
Q
what is a dissolving reaction ?
A
- a solute being put into a solvent to form a solution
- solute is pulled apart by the solvent and the particles are surrounded so that they are unable to rejoin
7
Q
what is the word equation to find out the energy released ?
A
energy released = mass of water x specific heat capacity of water x change in temperature
8
Q
what is the symbol equation to find out heat energy change ?
A
Q = mcΔT
9
Q
how do you calculate molar enthalpy change from heat energy change ?
A
- calculate heat energy change
- find mole (moles = mass ÷ Mr)
