Question

Electronic configuration of an element is 2, 8, 7 the atomic number of this element is _ and its symbol _

Answer 1

Answer:

atomic number is 17 and symbol is Cl

Answer 2

Answer: This may help you

Explanation:

The electron configuration of an element shows how many electrons are present. Add them to get the atomic number. 2+8+7 = 17.

Alternatively, there are 3 shells of electrons so the element is in period 3, and the last shell has 7 electrons so it is in Group (17 or VIIA). Trace to where the period number and group number intersect on the periodic table and you will get to chlorine.