S C Kheterpal, S N Dhawan and, P N Kapil Solutions for Chapter: Classification of Elements and Periodicity in Properties, Exercise 10: Competition Focus

Aqueous solutions of two compounds, $\mathrm{M}-\mathrm{O}-\mathrm{H}$and $\mathrm{M}\text{'}-\mathrm{O}-\mathrm{H}$ have been prepared in two separate beakers. If the electronegativity of $\mathrm{M}=3.5, \mathrm{M}\text{'}=1.72, \mathrm{O}=3.0$ and $\mathrm{H}=2.1$, then the solutions respectively are

In which of the following options the order of arrangement does not agree with the variation of property indicated against it ?

The elements which are radioactive and have been named after the names of the planet are

Which of the following are not $\mathrm{d}$-block elements ?

In which of the following pairs, both the species have nearly the same size ?

 Consider the following ionisation steps :

Select the correct statements :

Which of the following processes do not involve absorption of energy ?

The amount of energy released when $1\times {10}^{10}$ atoms of chlorine in vapour state are converted to ${\mathrm{Cl}}^{-}$ ions according to the equation,

$\mathrm{Cl}\left(\mathrm{g}\right) + {\mathrm{e}}^{-} \to {\mathrm{Cl}}^{-} \left(\mathrm{g}\right) \mathrm{is} 57.86 \mathrm{x} {10}^{-10} \mathrm{J}.$

Calculate the electron gain enthalpy of chlorine atom in terms of $\mathrm{eV}$ per atom.