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Random answers:
Bond energies: -1276/-1623 (some uncertainty here)
Explain why: Energy needed making bonds was greater than energy released breaking bonds
Balance equation: 2 and 2 somewhere
Efficiency of Kettle: Hydrogencarbonate ions thermally decompose to carbonate, then react with calcium ions to product a precitipates of calcium carbonate (limescale). Limescale is a bad conductor of electricity - more energy needed to heat water
Hard water cleaner q: Calcium and magnesium ions replaced by sodium and hydrogen ions
Benefits of hard water: contains calcium which strengthens teeth and bones
Element that has low boiling point: Flourine
What happens in the mixture of gases? Ammonia is liquified, then cooled - Nitrogen and Hydrogen are recycled
Specific heat capacity: 3444J (you had to use the mass of water (50g), not the 0.8g mass of fuel
How is methane obtained: Natural gas
Why air shouldn't be allowed in reactor: Air is a mixture of gases, the elements in air could have reacted with nitrogen and hydrogen in the reactor; wasting reactants, reducing yield. Other gases/elements entering the chamber also contaminates it.
Two boiling tubes: Tube A: fizzing/effervescence because acid is dissolving calcium carbonate
Tube B: calcium carbonate produced, solution goes cloudy
Sentence completion: - acid catalyst, ester
-Forward reaction is exothermic, so opposite reaction is endothermic
Filling in boxes: white precipitate for the halide test, no change for the others
What conditions are needed for highest yield of ammonia: 200 degrees, 1000 atm