MCQ
What changes does not occur when $K_2Cr_2O_7$ react with $H_2O_2$ solution
- AOrange colour of solution turns blue
- ✓$O.S$. of $Cr$ atom decreases
- C$O.S.$ of $Cr$ atom remains constant
- DNone of these
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$A\,\xrightarrow{{H{g^{2 + }}\,/\,{H^ + }}}B\,\xrightarrow{{NaB{H_4}}}C\,\xrightarrow[{conc.\,\,HCl}]{{ZnC{l_2}}}$ Turbidity within $5$ minutes.
Consider the following reactions $‘A’$ is
$(1)$ Oxidation of $1-$ phenylethanol
$(2)$ Reaction of benzalthanol with methyl magnesium bromide
$(3)$ Friedel craft’s reaction of benzene with acetyl chloride
$(4)$ Distillation of calcium benzoate

$A \to {\text{Product ;}}\,\, - \frac{{d[A]}}{{dt}} = {k_1}{[A]^o}$
$B \to {\text{Product ;}}\,\, - \frac{{d[B]}}{{dt}} = {k_2}{[B]}$
Units of $k_1$ and $k_2$ are expressed in terms of molarity $(M)$ and time $(sec^{-1})$ as
