`IE_2` of `3^(rd)` period elements is as follows. Why ?
`Mg lt Si lt Al lt P lt S lt Cl lt Ar lt Na.`

Among the second period elements the actual ionisation enthalpies are in the order Li lt B lt Be lt C lt O lt N lt F lt Ne . Explain why? Be has higher (Delta_iH)_1 than B

Among the second period elements the actual ionisation enthalpies are in the order Li lt B lt Be lt C lt O lt N lt F lt Ne . Explain why? O has lower (Delta_iH)_1 than N and F ?

Among the third period elements, the actual ionization enthalpies are in the order Na lt AI lt Mg lt SI lt S lt Plt CI lt Ar . Explain why: (i) Mg has higher Delta_(i)H than AI . (ii) S has lower Delta_(i)H than P and CI .

Explain the following data : Ionisation energy Cl lt H lt O lt N lt F .

Which of the following is(are) correct for if atom ? 1s lt 2s lt 2p lt 3s lt 3p 1s lt 2s = 2p lt 3s = 3p 1s lt 2p lt 3d lt 4s 1s lt 2s lt 4s lt 3d The correct choice is

The order of energy of orbitals is s lt p lt d lt f

If 0 lt x lt pi /2 then