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Chemistry

A Level

Describe how you would differentiate a sample of butanal and butan-2-one.

You would add tollen's reagent to both samples. The butanal would form a silver mirror, whereas, butan-2-one would remain unchanged. This is due to the fact that an aldehyde can be oxidised to a carboxyli...

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The Haber process is used to manufacture ammonia. Explain the optimum conditions for this reaction and why these conditions may not be used in industry

N₂(g)+3H₂(g) ⇋ 2NH₃(g) ΔH=-92kJmol^-1 (equation for question above)
According to Le Chatelier's principle, a system in dynamic equilibrium will shift th...

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State why it is initially unexpected for alkenes to undergo electrophilic addition with bromine. Explain why this reaction does indeed occur.

Bromine exists as Br₂, and since both bromine atoms are identical - their electronegativities identical, - the electron density is distributed evenly across the molecule (it is non-polar, the a...

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Explain the trend in first ionization energy down group 2. (3 marks)

The trend in first ionisation energy down a group: DECREASES due to:- Increase in atomic radius as there are more shells- Increased shielding...

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The Haber process is used to produce ammonia. (Insert equation here) Explain the optimum conditions for this reaction and why these may differ from the conditions used in industry.

N₂ (g)+3H₂ (g) ⇋ 2NH₃ (g) ΔH=-92kJmol^-1 (this is the equation for the above question)
According to Le Chatelier's principle, the position of equilibrium w...

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