Nitrogen atom has an atomic number of $7$ and oxygen has an atomic number of $8$. The total number of electrons in a nitrate ion $(NO_3^-)$ will be:

Lattice enthalpy and enthalpy of solution of $NaCl$ are $788 \ kJ \ mol^{-1}$ and $4 \ kJ \ mol^{-1}$ respectively. The hydration enthalpy of $NaCl$ is ....... $kJ \ mol^{-1}$

If one liter of air is repeatedly passed over heated copper and magnesium until no further reduction in volume occurs,the final volume of the air will be approximately ......... $mL$.

For the stoichiometric reaction occurring as shown in the figure,which option is incorrect?

$A$ person coming out of a swimming pool has $30 \ g$ of water on their body. How much heat in $kJ$ is required to evaporate this water? (The latent heat of vaporization of water is $40.79 \ kJ \ mol^{-1}$)

Mohr's salt is