10 minutes maximum! (can you do it in 5?) |
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1. Bond breaking ……
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2. Bond making is …..
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3. In an endothermic reaction, energy is …….
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4. In an exothermic reaction, the energy needed to break existing bonds is ….
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5. Hydrogen chloride gas is produced by reacting hydrogen with chlorine. The equation for this reaction is:
H2 + Cl2 → 2HCl The energy needed to break the bonds in H2 and Cl2 is 679kJ and the energy released on the formation of the bonds in 2HCl is 856kJ. |
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The overall energy change in kilojoules for this reaction is…
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Q6-8. When hydrogen ‘pops’ with a lighted splint it is reacting with oxygen to produce water. The equation for the reaction is: 2H2 + O2 → 2H2O Use the information from the table to help you answer these questions.
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6. Calculate the energy required to break all the reactant molecules into individual atoms.
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7. Calculate the energy released when the bonds in the product molecules are formed.
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8. Calculate the overall enthalpy change (energy change) for the reaction. • A. -486kJ |
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Q9-10. The combustion of methane is illustrated below in both equation and model form: The relevant bond energy values are: |
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9. The number of bonds being broken in the reactants and formed in the products is…..
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10. The enthalpy (energy) change for this reaction is ….
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Image by Gerd Altmann from Pixabay