Energetics (Triple) quiz Loading... 1. Is making new bonds exothermic or endothermic?Depends on the temperature of the surroundingsExothermicDepends on the reagentsEndothermicQuestion 1 of 16 Loading... 2. What is meant by the term endothermic?A reaction which will only be spontaneous at warm temperatures (above 100⁰C)A reaction in which heat energy is taken in (surroundings get colder)A reaction in which heat energy is given out (surroundings get hotter)A reaction which will only be spontaneous at cold temperatures (below 0⁰C)Question 2 of 16 Loading... 3. In a chemical reaction, the overall molar enthalpy is +87 kJ/mol. Is this reaction exothermic or endothermic?ExothermicDepends on the temperature of the surroundingsDepends on the reagentsEndothermicQuestion 3 of 16 Loading... 4. In a combustion calorimetry experiment, 0.78g of ethanol (C₂H₅OH) produced 12,540 J of heat energy. Calculate the molar enthalpy change.-213 kJ/mol (Amount = 46/0.78 = 59.0 mol. Answer = 12540/59.0 = 213 kJ/mol)-738 kJ/mol (Amount = 0.78/46 = 0.017 mol. Answer = 12540/1000/0.017 = 738 kJ/mol)-425 kJ/mol (Amount = 23/0.78 = 29.5 mol. Answer = 12540/29.5 = 425 kJ/mol)-369 kJ/mol (Amount = 0.78/23 = 0.034 mol. Answer = 12540/1000/0.034 = 369 kJ/mol)Question 4 of 16 Loading... 5. Explain why experimental values of enthalpy change differ from theoretical valuesDifferent equipment produces different results. Heat energy is lost to the surroundings. Not all the reactants are used upHeat energy is lost to the surroundings. Not all the reactants are used up.Different equipment produces different results. Heat energy is lost to the surroundingsDifferent equipment produces different results. Not all the reactants are used upQuestion 5 of 16 Loading... 6. Assuming bond energies in kJ/mol: H-C 412, C-C 348, O-H 463, C-O 360, C=C 612. Calculate the molar enthalpy change for the reaction: ethanol → ethene + water-45 kJ/mol (Some workings as follows. Breaking bonds 1583 kJ/mol. Making bonds 1487/mol. Making - breaking = 1487-1583 = -96 kJ/mol)+96 kJ/mol (Some workings as follows. Breaking bonds 1583 kJ/mol. Making bonds 1487/mol. Breaking - making = 1583-1487 = +96 kJ/mol)-45 kJ/mol (Some workings as follows. Breaking bonds 3231 kJ/mol. Making bonds 3186kJ/mol. Making - breaking = 3186-3231 = -45 kJ/mol)+45 kJ/mol (Some workings as follows. Breaking bonds 3231 kJ/mol. Making bonds 3186kJ/mol. Breaking - making = 3231-3186 = +45 kJ/mol)Question 6 of 16 Loading... 7. State the units of molar enthalpy change.mol/⁰CkJ/⁰CkJ/molJ/⁰C/molQuestion 7 of 16 Loading... 8. What does this diagram represent?Reaction profile for an exothermic reactionEnergy level diagram for an endothermic reactionEnergy level diagram for an exothermic reactionReaction profile for an endothermic reactionQuestion 8 of 16 Loading... 9. Are neutralisation reactions exothermic or endothermic?EndothermicExothermicDepends on the reagentsDepends on the temperature of the surroundingsQuestion 9 of 16 Loading... 10. Are displacement reactions exothermic or endothermic?Depends on the temperature of the surroundingsEndothermicExothermicDepends on the reagentsQuestion 10 of 16 Loading... 11. What is meant by the term exothermic?A reaction which will only be spontaneous at cold temperatures (below 0⁰C)A reaction in which heat energy is taken in (surroundings get colder)A reaction which will only be spontaneous at warm temperatures (above 100⁰C)A reaction in which heat energy is given out (surroundings get hotter)Question 11 of 16 Loading... 12. In an endothermic reaction, which is greater: the energy taken in when breaking bonds or the energy released when bonds are made?Energy taken in when making bondsEnergy taken in when breaking bondsEnergy released when bonds are madeDepends on the temperature of the surroundingsQuestion 12 of 16 Loading... 13. What does this diagram represent?Reaction profile for an exothermic reactionReaction profile for an endothermic reactionEnergy level diagram for an exothermic reactionEnergy level diagram for an endothermic reactionQuestion 13 of 16 Loading... 14. Use Q=mcΔT and c=4.18J/°C/g. 25cm³ of sulfuric acid is put into a boiling tube. The starting temperature is 21°C. A spatula of iron filings is added. After a while the temperature reaches 33°C. What is the total heat energy change?2153 J3383 J2.153 kJ1254 JQuestion 14 of 16 Loading... 15. In a calorimetry experiment to investigate the heat energy released by the combustion of ethanol, why should the water in the calorimeter be stirred?To ensure the heat energy is mixed evenly throughout all the waterTo prevent the water from evaporatingTo ensure the container does not get too hotTo allow the heat to spread evenly through the copper containerQuestion 15 of 16 Loading... 16. Use Q=mcΔT and c=4.18J/°C/g. A strip of magnesium is added to a beaker with 200cm³ of copper (II) sulfate. The temperature starts at 21.7°C and rises to a maximum of 23.1°C. What is the total heat energy change?1170 J2.153 kJ1247 J1944 kJQuestion 16 of 16 Loading... Related Posts:The entire quiz question bank!The entire quiz question bank (Double only)!Key Calculations quizEquilibria (triple) quizCondensation Polymers quizElectrolysis quiz Hydr0Gen2020-02-16T16:59:30+00:00Categories: Uncategorized|Tags: Quiz, Topic: Energetics| Share This Story, Choose Your Platform! 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