Question

Which is true for an element R present in IIIA group of the periodic table?
A)It forms halide of type $R{X_3}$
B)It has oxidation state of +3
C)It forms oxide of type ${R_2}{O_3}$
D)All the above

Answer 1

Periodic table is an arrangement of all the elements in accordance with their increasing atomic number and recurring chemical properties. They are further assorted in a tabular arrangement where a row is called as a period and a column is known as a group.

Complete step by step answer:
A tabular arrangement of elements in groups and periods which highlights the trends in properties of elements is known as a periodic table. Basically, there are eighteen vertical columns known as groups which are arranged from left to right and seven horizontal rows which are known as periods.

Now, the group IIIA elements or group 13 is known as Boron family because boron is the first member of this family. Moving further, to the given question, let us consider an element R which belongs to IIIA group of the periodic table. So, will have an oxidation state of +3.

Further, as halide is monovalent so the element R forms halides of the form $R{X_3}$ , so option A is correct. Now, as it has an oxidation state of +3 so, option B is also correct.
Moreover, as oxygen is divalent, so the element R forms oxides of the type ${R_2}{O_3}$

Therefore option C is also correct.
Hence, all the options are correct.

Note: In this group, boron has a high melting point whereas gallium has the lowest melting point. Moreover, group 13 elements never react with hydrogen because the valency of hydrogen is one and that of the boron family is three. The trihalides of this group are strong Lewis acids because they have the tendency to form compounds with electron-pair donors (the Lewis base).