The questions refers to the elements of the Periodic Table with atomic

1.	The questions refers to the elements of the Periodic Table with atomic numbers from 3 to 18. Some of the elements are shown by letters, but letters are not usual symbols of the elements:3456789101112131415161718ABCDEFGHIJKLMNOPWhich of these: (i) Is a noble gas ? (ii) Is a halogen ? (iii) Is an alkali metal ? (iv) Is an element with valency ?
Answer» (i) P is a noble gas with atomic number 18, i.e., 2, 8, 8. H is a also a noble gas with atomic number 10, i.e. 2, 8. (ii) G is halogen with atomic number 9, i.e. 2, 7. O is also a halogen with atomic number 17, i.e. 2,8, 7. (iii) A and I are alkali metals. (iv) D and L are elements with valency 4.

The questions refers to the elements of the Periodic Table with atomic numbers from 3 to 18. Some of the elements are shown by letters, but letters are not usual symbols of the elements:3456789101112131415161718ABCDEFGHIJKLMNOPWhich of these: (i) Is a noble gas ? (ii) Is a halogen ? (iii) Is an alkali metal ? (iv) Is an element with valency ?

Answer»

(i) P is a noble gas with atomic number 18, i.e., 2, 8, 8. H is a also a noble gas with atomic number 10, i.e. 2, 8.

(ii) G is halogen with atomic number 9, i.e. 2, 7. O is also a halogen with atomic number 17, i.e. 2,8, 7.

(iii) A and I are alkali metals.

(iv) D and L are elements with valency 4.