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GCSE

Explain why graphite can conduct electricity

Each carbon atom forms covalent bonds with three other carbon atoms and one electron from each carbon atom is delocalised.It is these delocalised electrons which allow electricity to be conducted as they ...

Answered by Tutor406540 D. • Chemistry tutor

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Magnesium oxide contains magnesium ions (Mg2+) and oxide ions (O2–). Describe what happens when magnesium atoms react with oxygen atoms to produce magnesium oxide.

magnesium ions loses two electrons becoming Mgoxygen gains two electron becoming OThis now means both the atoms have a full shell

Answered by Rabia D. • Chemistry tutor

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In the equation 2Na + 2H2O ---> 2NaOH + H2, is Na oxidised or reduced and why?

Write out the equation and explain the OIL RIG acronym.2Na + 2H₂O ---> 2NaOH + H₂Write the changes in oxidation state of Na. Na goes from an oxidation state of 0 to an oxidation ...

Answered by • Chemistry tutor

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Why does grinding a solid reactant down into smaller lumps increase the rate of a reaction? (2/3 marks)

As grinding down the solid increases the exposure of particles on the surface, this increases the frequency of reactant particle collisions which then increases the rate of reaction.

Answered by Isabelle H. • Chemistry tutor

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The equation for the reaction of carbon and nickel dioxide is: NiO + C ----> CO + Ni Calculate the percentage atom economy of this reaction to produce nickel to 3 significant figures.

Using a periodic table, you can find that: Molecular mass of carbon: 12Molecular mass of nickel: 59Formula mass of nickel oxide: 75 (=59+16)
Mass of all the reactants = 12+75=87Mass of the product we...

Answered by Emma N. • Chemistry tutor

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