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How do I do redox calculations?

For example,Iron(II) sulphate can be oxidised using acidified potassium permanganate solution. Calculate the mass of iron(II) sulphate which will completely react with 200 cm3 of 0.25 mol l-1 acidified pe...

Answered by Collette G. • Chemistry tutor

2361 Views

Calculate the percentage of Copper in Copper oxide (CuO, Mr=80). (3 marks)

Ar of Cu = 64 (1 mark) Percentage of copper in CuO = 64/80 x100 (1 Mark) Percentage of copper in CuO = 80% (1 mark)

Answered by Katie D. • Chemistry tutor

22489 Views

I don't understand how the first two quantum numbers fit into describing atoms.

There are 4 quantum numbers. Each one describes a specific electron's position relative to its nucleus.
The first one, "principal quantum number" describes the distance the talked about ele...

Answered by Nicole M. • Chemistry tutor

2180 Views

Propane burns completely to produce carbon dioxide and water. Describe how you would use limewater to show that carbon dioxide is produced.

If carbon dioxide is present, when the solution produced is mixed with lime water if it turns cloudy this will prove that carbon dioxide is present.

Answered by Huzair A. • Chemistry tutor

2990 Views

Predict whether the lattice energy of magnesium oxide, MgO, is more or less exothermic than the lattice energy of magnesium sulfide, MgS. Justify your answer in terms of the sizes and the charges of the ions involved.

To start with, we can clearly see that the difference between MgO and MgS is the anions, we have O(2-) and S(2-). As we know (from looking at the periodic table) O(2-) has a smaller ionic radius, and ther...

Answered by Huzair A. • Chemistry tutor

18747 Views