question_answer 5)

Which of the following species will have the largest and smallest size? \[Mg,M{{g}^{2+}},Al,A{{l}^{3+}}\]  

Answer:

Mg and Al, both belong to same period. Mg Al Atomic number 12 ; 13 Atomic size decreases from left to right across the period. Thus, Mg atom is larger in size than Al atom. Cation is smaller than its neutral atom. \[M{{g}^{2+}}\] ion is smaller than Mg atom and \[A{{l}^{3+}}\] ion is Smaller than Al atom. Thus, \[A{{l}^{3+}}\] ion size is the smallest and Mg atom is the largest in size among the given species.