Question

( x^{-2} ) has 18 electrons
( x^{-2} operatorname{has} 2 )
eleefrons more than protens
Then proton number ( =16 )
Neutron number ( =18 )
". Mass number 2 proton t neutron
[
begin{array}{l}
=18+16
=34
end{array}
]

# 2. J (4)1.25 x 10-13 1. Anion X2 contains 18 neutrons in its nucleus and 18 electrons out side of the nucleus, then mass number of main isotope of this element will be - (1) 25 46

Solution