Complete the chemical reaction. $ N{a_2}O + 2HCl \to ?$
(A) $ NaOH + {H_2} $
(B) $ 2NaCl + {H_2}O $
(C) $ NaOH + C{l_2} $
(D) $ 2NaCl + {O_2} $

Hint: Reactions are defined as the chemical integration of two or more compounds or elements to form new compounds and elements. These reactions can be various types, in one of the reactions the more reactive metal or non-metal replaces the less reactive metal or non-metal.

Complete answer:
Reactions are defined as the chemical combination of two or more compounds or elements in an enclosed or open container to form more elements and compounds. The compounds or limners that are reacting are called the reactants of the reaction. The reactants are the most important which decide everything regarding the equation or the chemical reaction. The compounds or elements formed by the reactants after their chemical reaction are called products.
Now in this reaction $ N{a_2}O + 2HCl \to $
The reactants that are already given to us are sodium oxide and hydrochloric acid. Now we know that hydrochloric acid is a very strong acid, therefore it dissociates very readily to give ions of hydrogen and chlorine present in the compound. The chlorine ion in the solution is more electronegative than the bonded oxygen in the sodium oxide. Now this chlorine ion attacks this sodium and forms a compound sodium chloride. The oxygen is present in the solution and also the hydrogen ion from the hydrochloric acid. Now the two moles of hydrogen react with one mole of oxygen to form water.
Therefore, at the end of the reaction we get sodium chloride and water.
The reaction is as follows: -
 $ N{a_2}O + 2HCl \to 2NaCl + {H_2}O $
The option B is correct; sodium chloride and water are fumed.

Note:
There are different types of reactions existing in chemistry. The different types of reactions existing are combination reaction where two elements combine to form a compound, precipitation reaction, where the final formation of products is denoted by the formation of precipitate by the product and further on many types of reactions exist.