Combined Science
Daily Exam Challenge: Combined Science (Higher)
Instructions
- • Use black ink or black ball-point pen. Draw diagrams in pencil.
- • Answer all questions in the spaces provided.
- • Do all rough work in this question paper. Cross through any work you do not want to be marked.
- • Show all your working out — marks may be awarded for correct working even if the answer is wrong.
Information
- • The total mark for this paper is 17.
- • The marks for each question are shown in brackets — use this as a guide as to how much time to spend on each question.
- • Questions labelled with an asterisk (*) are where the quality of your written communication will be assessed.
Answer all questions in the spaces provided.
A student measures the rate of photosynthesis at different temperatures. The rate increases from 10°C to 35°C, then rapidly decreases. (a) Explain why the rate increases between 10°C and 35°C. (b) Explain why the rate rapidly decreases above 35°C. (c) Sketch a graph to show the expected results.
Explain, using ideas about electron transfer, why the reaction between sodium and chlorine is an example of both oxidation and reduction.
A crane lifts a 500 kg steel beam 12 m in 8 seconds. The motor is rated at 10 kW. (g = 10 N/kg) (a) Calculate the useful energy transferred. (b) Calculate the total energy input from the motor. (c) Calculate the efficiency of the crane.
End of Questions
Total marks: 17