y level lower than the product energy level on the 'Energy' axis B1\n- Draws an upward curve connecting the reactants to the products, rising to a peak that is higher than both energy levels B1\n- Draws and labels a vertical arrow pointing upwards from the reactant level to the peak of the curve as the activation energy ($E_a$) B1","marks":3,"order":0,"markingRubric":null,"explanation":null,"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null},{"id":"a4ac5145-6b4d-4f38-b3b5-7d668e6a0b83","revisionId":"01460816-ea8a-425c-9c30-ad05c29215d4","questionNumber":null,"questionType":"LA","specification":"","difficulty":2,"difficultyBand":"easy","totalMarks":2,"sourceTitle":null,"calculatorUse":null,"isCalculation":true,"parts":[{"id":"fa495648-3ee2-493b-92ac-66e7b140fa97","label":null,"content":"In an experiment to measure the energy released by burning a fuel, the temperature of the water increased by $28.4^{\\circ}\\text{C}$. The heat energy transferred can be calculated using:\n\n$$\\text{heat energy (in J)} = 420 \\times \\text{temperature rise}$$\n\nCalculate the heat energy transferred to the water.","markscheme":"- Substitutes the given values into the equation: $420 \\times 28.4$ M1\n- Calculates the heat energy as $11928$ J (or $11.928$ kJ) A1","marks":2,"order":0,"markingRubric":null,"explanation":null,"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null},{"id":"a5f012fe-916d-4c3b-ae97-0530f8595ea7","revisionId":"b40a5ef8-f40a-4b8d-94e5-3f8b86ef65d2","questionNumber":null,"questionType":"LA","specification":"The thermal decomposition of calcium carbonate is an endothermic reaction.\n\nFigure 1 shows the reaction profile for this reaction.\n\n![Reaction profile diagram showing a horizontal line for the reactant, calcium carbonate, at a lower energy level on the left, and a horizontal line for the products, calcium oxide and carbon dioxide, at a higher energy level on the right. An upward curve connects the reactants to the products, representing the activation energy. The y-axis is labelled 'Energy' and the x-axis is labelled 'Progress of reaction'.](https://assets.mathsgenie.co.uk/question-image-redraws/sol-max-v1/a5f012fe-916d-4c3b-ae97-0530f8595ea7/image-1-1d5ba9f5a1c3d26d0d112432.svg)","difficulty":3,"difficultyBand":"easy","totalMarks":2,"sourceTitle":null,"calculatorUse":null,"isCalculation":false,"parts":[{"id":"6ab802c6-3fb7-40c3-8fcc-10dcf130e4fe","label":null,"content":"Explain how Figure 1 shows that the thermal decomposition of calcium carbonate is an endothermic reaction.","markscheme":"- Identifies that the products (calcium oxide and carbon dioxide) are at a higher energy level than the reactant (calcium carbonate) M1\n- Explains that this means energy is taken in or absorbed from the surroundings A1","marks":2,"order":0,"markingRubric":null,"explanation":null,"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null}],"subjectCode":"gcse_chemistry","summaries":[{"id":"03085a2b-d7ca-450e-9766-28f0e9ec29cf","difficultyBand":"easy","calculatorUse":null,"totalMarks":2},{"id":"03525fc1-082e-445d-b163-417fc6a7b4dd","difficultyBand":"medium","calculatorUse":null,"totalMarks":4},{"id":"038aa511-3081-47b5-a87c-8e1d845579d7","difficultyBand":"easy","calculatorUse":null,"totalMarks":2},{"id":"0e3e54f2-244d-4e37-97c2-4339776e42f5","difficultyBand":"medium","calculatorUse":null,"totalMarks":6},{"id":"0f1d0389-ce94-4039-84fd-d4505191376b","difficultyBand":"easy","calculatorUse":null,"totalMarks":1},{"id":"0f35ab31-8779-47a4-894e-3671c70e8302","difficultyBand":"easy","calculatorUse":null,"totalMarks":1},{"id":"13042463-2e58-4dec-8f23-25dadfbad8ab","difficultyBand":"easy","calculatorUse":null,"totalMarks":1},{"id":"13f960d8-9546-443c-b540-994b22cc4003","difficultyBand":"easy","calculatorUse":null,"totalMarks":1},{"id":"1675f0d1-56a7-4670-ac2d-9d2be70aa6a4","difficultyBand":"easy","calculatorUse":null,"totalMarks":2},{"id":"1af6922f-be1a-461d-8f2f-524a312

Heat energy changes in chemical reactions

Question 58

Heat energy changes in chemical reactions Questions

Heat energy changes in chemical reactions

Question 58

Heat energy changes in chemical reactions Questions