- ✓Synthetic petrol
- BThermosetting plastics
- CEthanol
- DBenzene
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The number of following statements which is/are correct about phenolphthalein is $.....$.
$A$. It can be used as an indicator for the titration of weak acid with weak base.
$B$. It begins to change colour at $pH =8.4$
$C$. It is a weak organic base
$D$. It is colourless in acidic medium

(Given, $\frac{ d (\ln K )}{ d \left(\frac{1}{T}\right)}=-\frac{\Delta H^{\ominus}}{ R }$, where the equilibrium constant, $K =\frac{ p _{ z }}{ p ^{\ominus}}$ and the gas constant, $R =8.314$ $\left.J K ^{-1} mol ^{-1}\right)$
($1$) The value of standard enthalpy, $\Delta H ^{\ominus}$ (in $kJ mol ^{-1}$ ) for the reaction is. . . . . . .
($2$) The value of $\Delta S^{\ominus}$ (in $J K ^{-1} mol ^{-1}$ ) for the given reaction, at $1000 K$ is. . . . . .
Give the answer or quetin ($1$) and ($2$)
$n$ $l$ $m_1$ $m_2$
(Rounded-off to the nearest integer) $\left[ K _{ b }=0.52 \,K \,kg\, mol ^{-1}\right]$