Phosphoric acid ionizes in three steps with their ionization constant values $K_{a_1}, K_{a_2}$ and $K_{a_3}$, respectively, while $K$ is the overall ionization constant. Which of the following statements are true?
A. $\quad \log \mathrm{K}=\log \mathrm{K}_{\mathrm{a}_1}+\log \mathrm{K}_{\mathrm{a}_2}+\log \mathrm{K}_{\mathrm{a}_3}$
B. $\mathrm{H}_3 \mathrm{PO}_4$ is a stronger acid than $\mathrm{H}_2 \mathrm{PO}_4^{-}$and $\mathrm{HPO}_4^{2-}$
C. $K_{a_1}>K_{a_2}>K_{a_3}$
D. $K_{a_1}=\frac{K_{a_3}+K_{a_2}}{2}$
Choose the correct answer from the options given below :
Match List-I with List-II
List - I (Ion) |
List - II (Group Number in Cation Analysis) |
||
---|---|---|---|
A | $\mathrm{Co}^{2+}$ | I | Group-I |
B | $\mathrm{Mg}^{2+}$ | II | Group-III |
C | $\mathrm{Pb}^{2+}$ | III | Group-IV |
D | $\mathrm{Al}^{3+}$ | IV | Group-VI |
Choose the correct answer from the options given below :
Higher yield of NO in $\mathrm{N}_2(\mathrm{~g})+\mathrm{O}_2(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NO}(\mathrm{g})$ can be obtained at $\left[\Delta \mathrm{H}\right.$ of the reaction $\left.=+180.7 \mathrm{~kJ} \mathrm{~mol}^{-1}\right]$
A. Higher temperature
B. Lower temperature
C. Higher concentration of $\mathrm{N}_2$
D. Higher concentration of $\mathrm{O}_2$
Choose the correct answer from the options given below :
Given below are two statements :
Statement-I : Benzenediazonium salt is prepared by the reaction of aniline with nitrous acid at $273-278 \mathrm{~K}$. It decomposes easily in the dry state.
Statement-II : Insertion of iodine into the benzene ring is difficult and hence iodobenzene is prepared through the reaction of benzenediazonium salt with KI.
In the light of the above statements, choose the most appropriate answer from the options given below: