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What is the electronic configuration for the sodium ion, Na+ ?

1s² 2s² 2p⁶
Na+ has +1 positive charge and therefore it has lost an electron.It loses its one electron in its 3s orbital as that electron is at the highest energy - h...

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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)

Answered by Sonali V. • Chemistry tutor

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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...

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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...

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