Pick the correct statement.I. Borax is a whit | vedclass

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(B) $I$. The structural formula of borax $(Na_2 B_4 O_7 \cdot 10 H_2 O)$ is $Na_2[B_4 O_5(OH)_4] \cdot 8 H_2 O$, which contains the $\left[B_4 O_5(OH)

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$I$ and $III$

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(B) $I$. The structural formula of borax $(Na_2 B_4 O_7 \cdot 10 H_2 O)$ is $Na_2[B_4 O_5(OH)_4] \cdot 8 H_2 O$, which contains the $\left[B_4 O_5(OH)_4\right]^{2-}$ unit. Thus, statement $I$ is correct.$II$. The aqueous solution of borax is basic in nature because it hydrolyzes to form $H_3 BO_3$ (a weak acid) and $NaOH$ (a strong base). The reaction is: $Na_2 B_4 O_7 + 7 H_2 O \longrightarrow 4 H_3 BO_3 + 2 NaOH$. Thus, statement $II$ is incorrect.$III$. In the borax bead test, cobalt $(Co)$ forms cobalt metaborate, $Co(BO_2)_2$, which is blue in color. Thus, statement $III$ is correct.Therefore, the correct statements are $I$ and $III$.

Column-$I$	Column-$II$
$A$. Diborane	$1$. Used as a flux for soldering metals
$B$. Gallium	$2$. Crystalline form of silica
$C$. Borax	$3$. Banana bonds
$D$. Alumino silicate	$4$. Low melting,high boiling,useful for measuring high temperatures
$E$. Quartz	$5$. Used as catalyst in petrochemical industries

Pick the correct statement.
$I$. Borax is a white crystalline solid containing $\left[B_4 O_5(OH)_4\right]^{2-}$ units.
$II$. The aqueous solution of borax is acidic in nature.
$III$. Cobalt gives a blue color in the borax bead test.

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Pick the correct statement.$I$. Borax is a white crystalline solid containing $\left[B_4 O_5(OH)_4\right]^{2-}$ units.$II$. The aqueous solution of borax is acidic in nature.$III$. Cobalt gives a blue color in the borax bead test.