Energetics (Triple) quiz Loading... 1. What is meant by the term endothermic?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 which will only be spontaneous at cold temperatures (below 0⁰C)A reaction in which heat energy is given out (surroundings get hotter)Question 1 of 16 Loading... 2. 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)-369 kJ/mol (Amount = 0.78/23 = 0.034 mol. Answer = 12540/1000/0.034 = 369 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)Question 2 of 16 Loading... 3. In a chemical reaction, the overall molar enthalpy is +87 kJ/mol. Is this reaction exothermic or endothermic?Depends on the reagentsExothermicEndothermicDepends on the temperature of the surroundingsQuestion 3 of 16 Loading... 4. Are displacement reactions exothermic or endothermic?Depends on the reagentsEndothermicExothermicDepends on the temperature of the surroundingsQuestion 4 of 16 Loading... 5. In an exothermic reaction, which is greater: the energy taken in when breaking bonds or the energy released when bonds are made?Depends on the temperature of the surroundingsEnergy taken in when making bondsEnergy released when bonds are madeEnergy taken in when breaking bondsQuestion 5 of 16 Loading... 6. What does the symbol ΔH meanenthalpy (energy) changespecific heat capacityheat energyexothermicQuestion 6 of 16 Loading... 7. 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?1247 J2.153 kJ1170 J1944 kJQuestion 7 of 16 Loading... 8. When a solid dissolves, is this process exothermic or endothermic?ExothermicDepends on the temperature of the surroundingsEndothermicDepends on the reagentsQuestion 8 of 16 Loading... 9. What does this diagram represent?Reaction profile for an exothermic reactionReaction profile for an endothermic reactionEnergy level diagram for an endothermic reactionEnergy level diagram for an exothermic reactionQuestion 9 of 16 Loading... 10. 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 container does not get too hotTo prevent the water from evaporatingTo ensure the heat energy is mixed evenly throughout all the waterTo allow the heat to spread evenly through the copper containerQuestion 10 of 16 Loading... 11. Explain why experimental values of enthalpy change differ from theoretical valuesHeat 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. Heat energy is lost to the surroundings. Not all the reactants are used upDifferent equipment produces different results. Not all the reactants are used upQuestion 11 of 16 Loading... 12. In a chemical reaction, the overall molar enthalpy is -87 kJ/mol. Is this reaction exothermic or endothermic?ExothermicDepends on the temperature of the surroundingsEndothermicDepends on the reagentsQuestion 12 of 16 Loading... 13. What is meant by the term exothermic?A reaction which will only be spontaneous at warm temperatures (above 100⁰C)A reaction in which heat energy is given out (surroundings get hotter)A reaction which will only be spontaneous at cold temperatures (below 0⁰C)A reaction in which heat energy is taken in (surroundings get colder)Question 13 of 16 Loading... 14. Explain, in terms of making and breaking bonds, why a reaction could be endothermicThe bonds in the reagents are weaker than the bonds in the productsBreaking the bonds is more favourable than making themThe energy needed to break the bonds is more than the energy released to make the bondsThe energy needed to break the bonds is less than the energy released to make the bondsQuestion 14 of 16 Loading... 15. 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?1254 J3383 J2153 J2.153 kJQuestion 15 of 16 Loading... 16. State the units of molar enthalpy change.kJ/molkJ/⁰Cmol/⁰CJ/⁰C/molQuestion 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! FacebookTwitterRedditLinkedInTumblrPinterestVkEmail