Chemical energetics — IGCSE Sciences - Co-Ordinated (0973) questions by topic
Chemical energetics questions interpret a reaction-pathway energy diagram, name the reaction type when carbon burns to heat a blast furnace, determine temperature changes across four reactions, and compare sodium hydroxide neutralising acid with melting ice cubes, worth from 1 to 10 marks.
Identify, state, determine and construct top the command words in this IGCSE Co-ordinated Sciences topic, with calculate also common: determine whether a reaction is exothermic or endothermic from a temperature change, not from the equation alone. 11 real questions from 2023 to 2025 papers sit below. Submitting each answer for instant marking flags an exothermic reaction wrongly labelled endothermic before the confusion spreads.
May–June 2025, Paper 11
Equal masses of four substances are added separately to different samples of 10 cm³ of dilute hydrochloric acid at 22 °C. The final temperature of each reaction mixture is…
Answer this question and get it marked →May–June 2025, Paper 12
Which statements about endothermic reactions are correct? 1 Thermal energy is taken in from the surroundings. 2 Thermal energy is released to the surroundings. 3 The temperature…
Answer this question and get it marked →May–June 2025, Paper 21
A reaction pathway diagram for a reaction is shown. On axes of energy / (kJ/mol) against progress of reaction, the reactants are at an energy of 100 kJ/mol, the curve rises to a…
Answer this question and get it marked →May–June 2025, Paper 22
The table shows the initial and final temperatures of four different reactions. reaction initial temperature / °C final temperature / °C --- --- --- 1 20 20 2 20 30 3 25 20 4 25…
Answer this question and get it marked →May–June 2025, Paper 41
The metal iron is extracted from hematite in a blast furnace. The extraction happens in several stages. In the first stage, carbon (coke) is burnt to provide heat and produce…
Answer this question and get it marked →May–June 2024, Paper 11
When aqueous sodium hydroxide reacts with dilute hydrochloric acid, the temperature of the reaction mixture increases. Ice cubes take in energy when they melt. Which row is…
Answer this question and get it marked →May–June 2024, Paper 21
A piece of sodium is added to water (2Na + 2H2O - 2NaOH + H2). Which row shows the type of reaction and the energy level diagram for the reaction? [Options A-D: type of reaction…
Answer this question and get it marked →May–June 2024, Paper 22
The energy level diagram for a reaction shows the products higher in energy than the reactants. [Energy level diagram: products above reactants.] The diagram represents an…
Answer this question and get it marked →May–June 2023, Paper 11
Which statement about exothermic and endothermic reactions is correct? A An endothermic reaction involves heat energy being taken in by the reactants. B An exothermic reaction…
Answer this question and get it marked →May–June 2023, Paper 12
Potassium chloride is added to water. The temperature of the solution decreases as the potassium chloride dissolves. Which type of reaction occurs? A endothermic B exothermic C…
Answer this question and get it marked →October–November 2023, Paper 21
The temperature of solution Q is 21 C. The temperature of solution P is 24 C. The two solutions are mixed. The temperature of the mixture is 31 C. Which statement is correct? A An…
Answer this question and get it marked →Other IGCSE Sciences - Co-Ordinated topics
- Motion, forces and energy (77)
- Electricity and magnetism (65)
- Practical skills (60)
- Organic chemistry (40)
- Waves (40)
- Atoms, elements and compounds (29)
- Organisms and their environment (28)
- Stoichiometry (24)
- Chemical reactions (22)
- The Periodic Table (22)
- Human nutrition (21)
- Reproduction (21)