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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

21421 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

1978 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

2699 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

17572 Views

Define a hydrocarbon and explain the difference between alkenes and alkanes.

A Hydrocarbon is an organic molecule containing only hydrogen and carbon atoms. Alkanes are saturated hydrocarbons, meaning they are only made up of single bonds. The carbons are 'saturated' with hydrogen...

Answered by Saskia H. • Chemistry tutor

7957 Views