Question

What type of reactions are represented by the following equations?
A.A+BC\[ \to \] AC+B
B.A+B\[ \to \]C
C.X\[ \to \]Y+Z
D.PQ+RS\[ \to \]PS+RQ
E.$A_2O_3$ +2B\[ \to \]$B_2O_3$+2A

Answer 1

Hint: Chemical reactions are of many types, they are decomposition reaction, combination reaction, single-displacement reaction, double-displacement reaction and combustion reaction. All these reactions are carried out in different ways and give different products. To answer the above question, we will first state the type of reaction and then look at how those reactions undergo.

Complete answer:
A.A+BC\[ \to \] AC+B: in this reaction, we see that an element A replaces/displaces the element B from its original place. As in this reaction, only 1 element A displaces another element B ,this reaction would be called a displacement reaction or single-displacement reaction.
B.A+B\[ \to \]C: this is the most basic reaction that we have learnt, two elements are combining to form the third. Here element A adds to element B to give a different element C.
C.X\[ \to \]Y+Z: this is the decomposition reaction, in this compound one compound X decomposes to give its components Y and Z.
D.PQ+RS\[ \to \]PS+RQ: look at the following reaction, it is a bit complex to understand. In this reaction we see that P displaces R from its place whereas R displaces P from its place. Hence it is called a double-displacement reaction.
E.$A_2O_3$ +2B\[ \to \]$B_2O_3$+2A: look at the answer to reaction 1 and compare, here we can see that B displaces A from its compound, hence clearly it is a single- displacement reaction.

Note:
Do not get confused between displacement and double displacement reactions. If you find that one element is displacing the other then next check if the displaced element is taking the position of 1st element that displaced it, if yes then it is double-displacement reaction otherwise it is single-displacement reaction. An easier way to distinguish between them is to check if there is an exchange of ions. If ions are exchanged it is a double-displacement reaction.