In the Hoope's process for refining of aluminium, the fused materials form three different layers and they remain separated during electrolysis also. This is because
The upper layer is kept attracted by the cathode and the lower layer is kept attracted by the anode
There is special arrangement in the cell to keep the layers separate
The $3$ layers have different densities
The $3$ layers are maintained at different temperatures
Give important trends and anomalous properties of boron.
Explain structures of diborane and boric acid.
$Be$ and $Al$ exhibit many properties which are similar, but the two elements differ in :
Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$ : Boric acid is a weak acid
Reason $R$ : Boric acid is not able to release $H ^{+}$ion on its own. It receives $OH ^{-}$ion from water and releases $H ^{+}$ion.
In the light of the above statements, choose the most appropriate answer from the options given below.
Which is true for an element $R$ present in III group of the periodic table