Describe the general trend in acid-base character of the oxides of the elements in the 3rd period: (Na to Ar)?

Question

* please give an example of one acidic oxide and one basic oxide and show with equations how these oxides react with water

Answer 1

The easy way to remember this is by examples as you indicated.

For Na, the oxide formed is Na2O or Sodium Oxide.This will react with water to form a very basic solution. Next is MgO or magnesium oxide, which react with water to also form a basic solution,

MgO + H2O ----> Mg(OH)2 (hydroxide makes it a base)

Then on the other side of the period, Sulfur forms SO2 or sulfur dioxide, and Chlorine forms ClO2. Both will react with water to form acidic solutions.

SO2 + H2O ---> H2SO3 (sulfurous acid)

Thus the general trend is from basic to acidic from left to right in a given period.

Answer 2

acidity increases from Na to Ar and basicity decreases,
NaOh is more basic than NaCl