Hey can someone please help with Q1, all parts except (iii) and (v) and an explanation would help alot! TIA
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INeutralisation reactions are NOT redox reactions. There is no change in oxidation state or exchange of electrons as hydrogen in HCl is already in a +1 state and ends as +1.
IIOxidationReductionThis combustion one is a bit complex because there are a crapload of electrons involved for longer alkanes. Anyhow, carbon can have oxidation states from -4 to +4, and ethane carbon exists as -3 because of the 3 +1 hydrogens bonded to each; and molecules must have a total state of 0. Therefore, carbon changes from a -3 to a +4 from ethane to carbon dioxide. And, oxygen goes from 0 in diatomic to -2 in carbon dioxide and water.
IVEsterification is a redox reaction.
The alcohol is oxidised, and the alkanoic acid is reduced.
This
guide explains it.
VIThis decomposition reaction is not a redox reaction and has no oxidation/reduction involved because the calcium, oxygen, and carbon all start and end with the same oxidation states of 2+, 2-, and 4+ respectively.
VIIThis is the same with question I because it is also a neutralisation reaction. There is an exchange in proton to form ammonium, which then bonds with the already negative chlorine. Hence, there are no changes in oxidation states.
VIIIThis one is a redox reaction because aluminium 3+ ions are reduced into solid aluminium by gaining 3 electrons each.
The oxygen is oxidised because it starts as a 2- ion and gets gains the electrons from aluminium ions to form oxygen gas.
This explains it nicely with equations.IXOxidationReductionThis is a redox reaction because hydrogen goes from +1 in water to 0 in diatomic hydrogen, and oxygen goes from -2 in water to 0 in diatomic oxygen.
Basically, you have to watch out for changes in oxidation states where electrons are being exchanged.
Hope this helps