Required Practical - Temperature changes in solutions Flashcards
1
Q
What is the purpose of this experiment?
A
To find out how different variables affect energy changes in solutions.
2
Q
What is an exothermic reaction?
A
the release of energy (heat exerted)
3
Q
What is an endothermic reaction?
A
the absorption of energy (gets cold)
4
Q
Method:
A
- Set up equipment (Pyrex beaker, Polystyrene cup, thermometer and HCL)
- Take the temperature of the acid
- Add the metal powder and stir
- Record the highest temperature the reaction mixture reaches
- Calculate the temperature change
- Repeat using a different metal
5
Q
What is the independent variable?
A
The metal used
6
Q
What is the dependent variable?
A
The temperature change
7
Q
What are the control variables?
A
the type, concentration and volume of acid
8
Q
Hazards:
A
Corrosive acid could damage experimenters eyes
9
Q
What is labelled as axis on an energy level diagram?
A
x-axis = progress of reaction Y-axis = energy
10
Q
Order of energy level reaction?
A
reactants, energy given out, activation energy, products
11
Q
What is a catalyst?
A
A substance that speeds up the rate of a chemical reaction, but is not used up in the reaction itself
