chem paper answers (1 Viewer)

jazz519

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11) For a basic salt remember we need a strong base and a weak acid to have reacted. Ammonium comes from ammonia (weak base) and chloride from HCl(strong acid), so in fact ammonium chloride would be an acidic salt.

The correct answer is A (pottasium hydroxide is a strong base (strong bases are from group 1 and 2) and citrate is from citric acid weak acid
 

cloud edwards

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ONE more question; 21 b) Explain the need for a xataylst in the dehydration of ehtanol. I got the catalyst to conc sulfuric acid but i don't know the speciifc need
 

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ONE more question; 21 b) Explain the need for a xataylst in the dehydration of ehtanol. I got the catalyst to conc sulfuric acid but i don't know the speciifc need
Conc sulfuric acid is a dehydrating agent, so it will remove the water from ethanol.
 

jazz519

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ONE more question; 21 b) Explain the need for a xataylst in the dehydration of ehtanol. I got the catalyst to conc sulfuric acid but i don't know the speciifc need
It's three marks so need to go into detail with stuff. I would define a catalyst. Explain why it speeds up reaction rate. Then state that in this reaction the catalyst acts a dehydrating agent. Lastly, linking back to benefits of using a catalyst as well such as saves money as you get a lower temperature needed due to more reactants being able to overcome the lower activation energy barrier.
 

jazz519

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Can you explain this again. Sorry, my maths is horrible. What do you convert the percentage into when you times it by 100 first? And then dividing it by 100?
oh the dividing bit is converting from percentage to decimal and the 100mL is from the v/v bit
 

jazz519

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Where did the *10^6 come from?
its parts per million (so the first fraction establishes a ratio of ozone to air) and the multiplication bit says how many ozone molecules there are in a million molecules of air
 

jazz519

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If it was parts per billion then it would be x10^9
 

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