Periodic Trends in the Properties of Elements

The ions  ${\mathrm{O}}^{2-},{\mathrm{F}}^{-},{\mathrm{Na}}^{+},{\mathrm{Mg}}^{2+}\mathrm{and}{\mathrm{Al}}^{3+}$ are isoelectronic. Their ionic radii show:

Assertion. ${\mathrm{Na}}^{+}$ and ${\mathrm{Al}}^{3+}$ are isoelectronic but the magnitude of the ionic radius of ${\mathrm{Al}}^{3+}$ is less than that of ${\mathrm{Na}}^{+}$ .

Reason. The magnitude of effective nuclear charge of the outer shell electrons in ${\mathrm{Al}}^{3+}$ is greater than in ${\mathrm{Na}}^{+}$ .

The boiling point of bromine is_____than chlorine(greater/lower).

The boiling point of phosphorus is greater than nitrogen.

The correct order of boiling point of halogens is
 

The correct order of boiling point of halogens 

The metallic radius is half of the total distance between the nuclei of two adjacent atoms in a _____.

Mark the following statement as true or false.

Metallic radii increases across the period due to an increase in the effective nuclear charge.

How does metallic radius defined?

Arrange $\mathrm{B}\mathrm{e},\mathrm{}\mathrm{M}\mathrm{g},\mathrm{}\mathrm{C}\mathrm{a},\mathrm{}\mathrm{S}\mathrm{r}$ in the ascending order of ionisation enthalpy.

The correct order of $1^{\mathrm{st}}$ ionisation enthalpy among the following elements $\mathrm{Be}, \mathrm{B}, \mathrm{C}, \mathrm{N}, \mathrm{O}$ is

The electron affinity of bromine is $3.36 \mathrm{eV}$. How much energy in $\mathrm{kcal}$ is released when $8 \mathrm{g}$ of bromine is completely converted to ${\mathrm{Br}}^{-}$ ions in the gaseous state? ($1 \mathrm{eV}=23.06 \mathrm{kcal} {\mathrm{mol}}^{-1}$). (Give the value rounded-off to the nearest integer)

Amongst the following, the most basic oxides are

Which of the following process(es) is/are endothermic?

$\left(\mathrm{i}\right)$ $\mathrm{O}\left(\mathrm{g}\right)⟶{\mathrm{O}}^{+}\left(\mathrm{g}\right)$        $\left(\mathrm{ii}\right)$ $\mathrm{Na}\left(\mathrm{g}\right)⟶{\mathrm{Na}}_{\left(\mathrm{g}\right)}^{+}$           $\left(\mathrm{iii}\right)$ ${\mathrm{S}}^{-}\left(\mathrm{g}\right){⟶\mathrm{ }\mathrm{S}}^{2-}$
 $\left(\mathrm{iv}\right) \mathrm{P}\left(\mathrm{g}\right)⟶{\mathrm{P}}^{-}\left(\mathrm{g}\right) \left(\mathrm{v}\right){\mathrm{O}}_{}^{-}\left(\mathrm{g}\right)⟶{\mathrm{O}}_{}^{2-}\mathrm{g}$           $\left(\mathrm{vi}\right)$ $\mathrm{N}\left(\mathrm{g}\right)⟶{\mathrm{N}}^{-}\left(\mathrm{g}\right)$

$\mathrm{M} \left(\mathrm{g}\right)\to {\mathrm{M}}^{+} \left(\mathrm{g}\right)+{\mathrm{e}}^{-}; \mathrm{\Delta H}=100 \mathrm{eV}$

$\mathrm{M} \left(\mathrm{g}\right)\to {\mathrm{M}}^{2+} \left(\mathrm{g}\right)+2{\mathrm{e}}^{-}; \mathrm{\Delta H}=350 \mathrm{eV}$

Which of the following is the correct statement with respect to the above reactions?

Amongst isoelectronic species, smaller the positive charge on the cation, smaller is the ionic radius.