Give the formulae of the compounds formed from the following set of elements.

(i) Carbon and hydrogen


(ii) Nitrogen and magnesium


(iii) Sodium and phosphorus


(iv) Potassium and oxygen


(v) Boron and oxygen

(i) Carbon and hydrogen:


CH4 (methane)


C2H6 (ethane)


(ii) Nitrogen and magnesium:


Magnesium nitrate



Formula: Mg3(NO3)2


(iii) Sodium and phosphorus:


Sodium phosphate



Formula: Na3PO4


(iv) Potassium and oxygen:


Potassium oxide



Formula: K2O


(v) Boron and oxygen:


Boron oxide



Formula: B2O3


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