Which of the following statements about the interstitial compounds is incorrect?
They are much harder than the pure metal.
They have higher melting points than the pure metal.
They retain metallic conductivity.
They are chemically reactive.
Describe the shapes of $BF $$_{3}$ and $BH _{4}^{-}$. Assign the hybridisation of boron in these species.
Which reaction involves a change in the electron pair geometry for the underlined element ?
The dissolution of $Al(OH)_3$ by a solution of $NaOH$ results in the formation of
Which of the following compounds is formed by addition of mineral acid to an aqueous solution of borax ?
When metal $X$ is treated with sodium hydroxide, a white precipitate $(A)$ is obtained, which is soluble in excess of $NaOH$ to give soluble complex $(B)$. Compound $(A)$ is soluble in dilute $HCl$ to form compound $(C)$. The compound $(A)$ when heated strongly gives $(D)$, which is used to extract metal. Identify $(X), (A), (B), (C)$ and $(D)$. Write suitable equations to support their identities.