Question

$\huge \blue {\mathfrak {\underline {\underline{Question : - }}}}$
Which of the following contains same number of elements?
A) 1st period & zero group
B) 6th period & Ill B group
C) 5th period & III B group
D) 3rd period & VII A group

(NO COPIED ANSWERS AND IRRELEVANT ANSWERS)​

Answer 1

Answer:option d is right

REASON: 3rd period and VII A group contains same number of elements .

They have 8 elements each

EXPLANATION:

OPTION A:

1ST PERIOD:

It consists of hydrogen and helium.there are only TWO elements present in it.

ZERO GROUP:

it is also known as noble group elements or rare group or inert group elements.

The elements are helium,neon,argon,Krypton,xenon,radon and new element oganesson.there are SEVEN elements.

SO OPTION A IS INCORRECT

OPTION B:

6TH PERIOD:

it has 32 elements in total.it also includes inner transition elements.

III B GROUP:

13th group is called III B group.it has boron , aluminium,gallium ,indium,thallium , a new element nihonium and two inner transition elements.so totally it has EIGHT elements.

SO OTION B IS INCORRECT

OPTION C:

5TH PERIOD:

It has 18 elements.

It does not include inner transition elements.

III B GROUP:

it has EIGHT elements.

SO OPTION C IS INCORRECT.

OPTION D:

3RD PERIOD:

It has EIGHT elements.

They are sodium, magnesium, aluminium,silicon, phosporous,sulphur,chlorine,argon.

VII A GROUP:

It is called 17th group.these are halogens.the elements are fluorine, chlorine,bromine,iodine, astatine ,new element Tennessine and two more inner transition elements.so totally EIGHT elements are present.

SO OPTION D IS RIGHT

REFERENCE:

check PERIODIC TABLE for clarification.

Explanation:

Answer 2

Answer:

.

.

.

.

6th period contains 32 elements (18(Cs−Rn)+14 lanthanides (Ce−Lu=32).

IIIB group also contains 32 elements (4 elements listed in IIIB group, 14 lanthanides and 14 actinides so totally 4+14+14=32).

So, option D is correct.