Fig. 2.1 gives the outcomes for $120\,\text{s}$ and $300\,\text{s}$. Transfer the readings from Fig. 2.1 into Table 2.1, giving each one to the nearest $0.5\,^{\circ}\text{C}$.
Calculate the greatest temperature change in the investigation.
Describe the patterns shown in the results in Table 2.1.
Suggest the temperature of the mixture if it is left for $60\,\text{minutes}$. Explain your answer.
Describe the energy change when the solid dissolves in water. Explain how the results in Table 2.1 support your answer.
Explain why it is important for the student to stir the mixture.
The calculated maximum temperature change is not the actual value for this investigation. This could be because the water volume and the temperature are not measured exactly. Explain how to obtain a more precise temperature measurement.
The calculated maximum temperature change is smaller than the true value for this investigation. Suggest a reason for this, other than the precision of measurements. Describe an improvement to the method which reduces this error.