Why is the ionisation enthalpy of hydrogen higher than that of sodium?
(N/A) Both hydrogen and sodium have one electron in the valence shell. However,the atomic size of hydrogen is much smaller than that of sodium. Consequently,the valence electron in hydrogen is much closer to the nucleus and experiences a stronger electrostatic force of attraction. Therefore,the ionisation enthalpy of hydrogen $(1312 \ kJ \ mol^{-1})$ is significantly higher than that of sodium $(496 \ kJ \ mol^{-1})$.
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Similar Questions
In the second period of the long form of the periodic table,an element $X$ has the second lowest first ionization enthalpy and element $Y$ has the second highest first ionization enthalpy values. What are $X$ and $Y$?
If $X$ and $Y$ are the second ionisation potentials of alkali and alkaline earth metals of the same period,then:
Medium
View SolutionAssertion $(A)$: $16$th group elements have higher ionisation enthalpy values than $15$th group elements in the corresponding periods.
Reason $(R)$: $15$th group elements have half-filled stable electronic configurations.
Reason $(R)$: $15$th group elements have half-filled stable electronic configurations.
Which element has the maximum first ionization potential?
The first ionization enthalpies of $Mg$ and $Al$ can be expected to be
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