Effect of temperature on reaction rates and the concept of activation energy: past paper questions
Real questions on effect of temperature on reaction rates and the concept of activation energy
The newest 20 of 46 written questions. Open one to see it on the real paper.
- 9701/41 · October/November 2025 · Q3d[1]
Describe the effect of increasing temperature on the rate constant and on the rate of a reaction.
See it on the paper → - 9701/42 · October/November 2025 · Q2d[1]
NO 2 also reacts with ozone, O 3 . The rate equation is shown. rate = k 1 [NO 2 ] Under certain conditions, the value of k 1 is 0.0848 s –1 . The reaction has a constant half-life under these conditions. Calculate the half-life in seconds. half-life = s
See it on the paper → - 9701/43 · October/November 2025 · Q3d[1]
Describe the effect of increasing temperature on the rate constant and on the rate of a reaction.
See it on the paper → - 9701/23 · May/June 2025 · Q3b(ii)[1]
Define activation energy, E A .
See it on the paper → - 9701/51 · May/June 2025 · Q2f[1]
k increases with temperature. A second experiment is carried out at a higher temperature. Sketch a suggested line of best fit on Fig. 2.1 for the second experiment.
See it on the paper → - 9701/53 · May/June 2025 · Q2a[2]
Give two reasons that explain why the use of iced water in step 4 decreases the rate of reaction. reason
See it on the paper → - 9701/41 · May/June 2024 · Q5c[1]
Describe the effect of an increase in temperature on the rate constant and the rate of reaction 1.
See it on the paper → - 9701/43 · May/June 2024 · Q5c[1]
Describe the effect of an increase in temperature on the rate constant and the rate of reaction 1.
See it on the paper → - 9701/51 · May/June 2024 · Q2c[2]
A student carries out the procedure at three different temperatures and records the measurements in Table 2.1. Complete Table 2.1. Record values for temperature to the nearest whole number and the 1 values for to four decimal places. t Table 2.1 temperature, T / °C time, t / s 15 176 24 92 32 62 temperature, T / K 1 –1...
See it on the paper → - 9701/51 · May/June 2024 · Q2d(i)[2]
Use the results from Table 2.2 to plot a graph on the grid in Fig. 2.1 to show the 1 1 relationship between log c m and . Use a cross (×) to plot each data point. Draw a line t T of best fit. – 0.8 – 1.0 – 1.2 – 1.4 – 1.6 ( 1 t ( – 1.8 – 2.0 – 2.2 – 2.4 – 2.6 0.0028 0.0029 0.0030 0.0031 0.0032 0.0033 0.0034 0.0035 1 –1...
See it on the paper → - 9701/51 · May/June 2024 · Q2d(iii)[3]
An equation relating time and temperature variables is shown. 0 . 434 E A 1 + constant log c m = – t RT Determine the activation energy, E A , of this reaction using this equation and your answer to (d)(ii). (If you were unable to find the gradient in (d)(ii), then use the value –3.21 × 10 3 K. This is not the correct...
See it on the paper → - 9701/53 · May/June 2024 · Q2a[1]
Suggest a reason why it is necessary to wait for 10 minutes in step 5.
See it on the paper → - 9701/53 · May/June 2024 · Q2b(i)[1]
State the temperature measurements that should be taken and at which stage in the procedure they should be taken.
See it on the paper → - 9701/53 · May/June 2024 · Q2b(ii)[1]
State how to use the temperature measurements to determine an accurate value for the temperature of the mixture during the reaction.
See it on the paper → - 9701/53 · May/June 2024 · Q2c[2]
A student carries out the procedure at three different temperatures and records the measurements in Table 2.1. Complete Table 2.1. Record values for temperature to the nearest whole number and the 1 values for to four decimal places. t Table 2.1 temperature, T / °C time, t / s 15 176 24 92 32 62 temperature, T / K 1 –1...
See it on the paper → - 9701/53 · May/June 2024 · Q2d(i)[2]
Use the results from Table 2.2 to plot a graph on the grid in Fig. 2.1 to show the 1 1 relationship between log c m and . Use a cross (×) to plot each data point. Draw a line t T of best fit. – 0.8 – 1.0 – 1.2 – 1.4 – 1.6 ( 1 t ( – 1.8 – 2.0 – 2.2 – 2.4 – 2.6 0.0028 0.0029 0.0030 0.0031 0.0032 0.0033 0.0034 0.0035 1 –1...
See it on the paper → - 9701/53 · May/June 2024 · Q2d(ii)[2]
Determine the gradient of your line of best fit in Fig. 2.1. State the coordinates of both points you use in your calculation. These must be selected from your line of best fit. Give the gradient to three significant figures. coordinates coordinates gradient = K
See it on the paper → - 9701/53 · May/June 2024 · Q2d(iii)[3]
An equation relating time and temperature variables is shown. 0 . 434 E A 1 + constant log c m = – t RT Determine the activation energy, E A , of this reaction using this equation and your answer to (d)(ii). (If you were unable to find the gradient in (d)(ii), then use the value –3.21 × 10 3 K. This is not the correct...
See it on the paper → - 9701/52 · February/March 2024 · Q2c(iii)[1]
Identify one variable that needs to be controlled, apart from concentrations and volumes of solutions.
See it on the paper → - 9701/41 · October/November 2023 · Q8d(i)[1]
Identify reagent J and any necessary conditions.
See it on the paper →
What examiners said
These conditions were not well known and ‘concentrated’ was frequently omitted with the description of potassium manganate(VII).
— Examiner report, October/November 2023, 9701/41 Q8(d)(i) (Cambridge)
The temperature was kept below 5 oC to prevent decomposition of benzene diazonium chloride during the preparation of the 0.200 moldm-3 solution. If this did occur, then the concentration of the solution would have been lower than desired.
— Examiner report, October/November 2023, 9701/53 Q2(c)(v) (Cambridge)
Most candidates gave a correct answer. Some only mentioned one of k or rate.
— Examiner report, May/June 2023, 9701/42 Q4(a)(v) (Cambridge)
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