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Zinc reacts with sulphuric acid (Zn + H2SO4 --> ZnSO4 + H2). Write out two separate equations for the species that are oxidised and reduced.

Zn --> Zn^2+ + 2e- (OXIDATION) H2^2- + 2e- --> H2 (REDUCTION)

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State and explain the difference in base strength between phenylamine and ammonia.

Phenylamine is a weaker base than ammonia. The lone pair on the nitrogen of phenylamine is delocalised into the ring, thus making the lone pair less available to combine with hydrogen ions. Also, in order...

Answered by • Chemistry tutor

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A student wanted to make 10.0 g of zinc chloride. The equation for the reaction is: ZnO(aq) + 2HCl(aq) → ZnCl2(aq) + H2O(l) Calculate the mass of zinc oxide the student needs to react with the dilute acid to make 10.0 g of zinc chloride. [4 marks]

What do we know from the question? 1. we know the balanced equation 2. we know the mass of zinc chloride we want to form. using the equation number of moles = mass/Mr we can calculate the number of moles ...

Answered by Arun S. • Chemistry tutor

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How many molecules of water are present in 5g sample?

In order to measure the amount of water molecules, we need to use following equation:
n = m / M where n is the amount of water molecules in molesm is the mass in grammesM is the molecular mass of wat...

Answered by • Chemistry tutor

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Explain the bonding in and the shape of a benzene molecule.

Stage 1 -Bonding 1a) Each C has three (covalent) bonds 1b) Spare electrons (in a p orbital) overlap (to form a pi cloud) 1c) delocalisation
Stage 2 -Shape 2a) Planar 2b) Hexagon/6 carbon ring/120o b...

Answered by Yousif C. • Chemistry tutor

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