Which of the following sets does not belong to a group?
(a) Li, Na, K
(b) B, C, N
(c) B, Al, Ga
(d) O, S, Se
Answers
Answer:
(b)B,C,N is the set does not belong to a group.
Answer:
So as per your options provided Option b) B, C, N do not belong to the same group.
Explanation:
Periodic table has groups in which elements are placed in the periodic table. These are the columns that are in the PT (Short form for Periodic Table here). The modern time PT has total of 18 groups. But not all of the groups are important.
The vertical columns that are present on the PT are termed as the Groups. They are also called as the families as the elements that are placed in the same group have common or similar chemical properties.
The elements that belong to the same group have same valence (number of electrons that are present in the outer most orbit of the atom).
Just for your notice:- the rows run horizontally along the PT.
When speaking of the PT, all groups are not considered as important as 1, 2 groups and between 13 to 18 are considered as important. These are also elements that are available naturally and in abundant.
Now lets look at first option a) Li, Na , k these are elements that belong to the same group Group 1. They are named as Alkali metals and so they belong to the same group.
b) B , C , N Now the B (Boron Group) is the 13th group in the PT. These elements include B, Al, Ga, In, Ti and Uut. So it is certain that B, C, N do not belong to the same group. Thus this option is wrong.
c) B, Al and Ga these elements belong to the Group 13, so they are from the same group.
d) O, S, Se these are elements that also belong to the same group – Group 16. Thus this option is correct.
So as per your options provided Option b) B, C, N do not belong to the same group.