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Chemistry

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How do you determine the shape and bond angle of an ammonia molecule?

Firstly, how many electrons does nitrogen have in its outer shell?... Nitrogen is in group 5, so 5.How many more electrons does nitrogen need to give it a full outer shell?... 8 electrons provide a full o...

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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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