CORE PRACTICALS

Question 1

What is the first stage of the calorimetry experiment? (1)

Answer 1

Add a known volume of acid to an insulated container (I.e a polystyrene cup) and measure the temperature.

Question 2

What is the second stage of the calorimetry experiment? (2)

Answer 2

Then add a known volume of alkali and record the temperature of the mixture at regular intervals over a period of time (stir solution to make sure it’s evenly heated).

Question 3

What is the third stage of the calorimetry experiment? (1)

Answer 3

Find the temperature change for the experiment. Use it calculate the enthalpy change of the reaction. (q=mC T)

Question 4

How do you find the temperature change without using a graph? (1)

Answer 4

Subtract the starting temperature from the highest temperature.

Question 5

What is the problem with calculating the temperature change without a graph? (1)

Answer 5

Not an accurate value because of heat loss to surroundings.

Question 6

How to you calculate the temperature change using a graph? (2)

Answer 6

Draw a line of best fit, one through the points before the reaction started and one through the points after it started.
The distance between the two lines at the time the reaction started (before any heat was lost) is the accurate temperature change for the reaction.