a. Define Valency. b. Write the symbol and valency of the following : (i) Oxygen (ii) potassium 7. a. Magnesium burns in Oxygen to form Magnesium Oxide. a) Name the reactants b) Name the Products c) Write the word equation for the above reaction.

⚘ Your Answers:

A) Valency is the combining capacity of any element. Valence electrons refers to the electrons found in the outermost shell of the atom of the element.

B) Symbol and valency:

Oxygen(O) = (At. no. 8) = -2(Valency)Potassium(K) = (At. no. = 19) = +1(Valency)

C) The reaction would be:

Reactants = Magnesium and Oxygen Products = Magnesium oxideWord equation:

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