Endo/Exo
Measuring temperature changes
Reaction Profiles
100
What happens to temperature in an exothermic reaction?
Increases
100
Why use a digital thermometer instead of an analog one?
Has a higher resolution
100
Does this reaction profile show you an endothermic or exothermic reaction?
Exothermic
200
Define endothermic.
Energy is absorbed/taken in (1)
From the surroundings (1)
200
TRIPLE POINTS!
You have 3 fuels in spirit burners. You want to figure out which one released the most heat. The equipment you have are:
- Top pan balance
- Beaker of water
- Tripod
- Thermometer
- Stopwatch
• Weighs the burner with an alcohol in it
• Places the burner below a beaker of water
• with a thermometer to measure the initial temperature
• Allows the alcohol to burn for a set time
• Records the temperature of the water at the end
• Repeats the experiment in exactly the same way, i.e., states same mass of water
• States that the fuel that produces the higher temperature rise gives out the most heat An equally acceptable /
200
Define activation energy.
Minimum energy required for a reaction to occur.
300
Give 3 examples of exothermic reactions.
Combustion
Neutralisation
Respiration
300
List 3 improvements to Sandy's practical set up so that she gets more accurate results.
- Polystyrene cup
- lid
- Heatproof mat
- Digital thermometer
300
What the letter showing:
1. Activation energy
2. Heat change
3. Products
1.B
2.E
3. D