Give the symbol for:

a. the cation possessing a positive one charge that is isoelectronic with argon.
b. the anion possessing a negative two charge that is isoelectronic with krypton.

a. K⁺

b. Se²⁻

Explanation:

Isoelectronic species are those that have the same number of electrons.

a.

Ar has 18 electrons. K has 19 electrons, so when it loses 1 electron to form K⁺, it is isoelectronic with Ar.

b.

Kr has 36 electrons. Se has 34 electrons, so when it gains 2 electrons to form Se²⁻, it is isoelectronic with Kr.

answer : (a) volume of the gas = 8.67 ×   l

                (b) second virial coefficient b = -1.21226 l/mole

solution :   given,     t = 300k

                                p = 20atm

                                z = 0.86

                                n = 8.2 mmoles = 8.2 × moles

                                r =   0.082 l atm/k/mol

        find,     (a) volume of gas   and (b) second virial coefficient b at 300k.

formula used :            

                          and            

(a)            

                    = \times 0.082\times 300}{20}[/tex]

                    = 8.67 ×   l

(b)      

                    = (0.00867-1) × 8.659

                    = - 8.5839 l/mole