Question

Electronic configuration of element T is 2, 8, 7. Under which category this element belongs to?

• A. Alkali metal
• B. Alkaline metal
• C. Noble gases
• D. Non-metal

Answer 1

The correct option is D Non-metal

Given 2, 8, 7 in this first shell can have 2 electrons where as second shell can have 8 electrons 2 in s orbital and 6 in p orbital.

Hence remaining 7 must be only in third shell as third shell has capacity of 18 electrons.

Here in valence shell we have 7 electrons in which 2 are in s orbital and 5 are in p orbital in which 1 is unpaired.

Hence valency electrons is 7 for atomic number 17 that is chlorine and valency is 1 as it has to get one electron to get octet configuration. As it is accepting an electron it is a non metal.