MCQ
The percentage of formaldehyde in formalin is:
- A40%
- B30%
- C20%
- D10%
Explanation:
The percentage of formaldehyde in formalin is 40%
10ml formalin contains 40ml formaldehyde and 60ml of water.
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$Ag\left( s \right)\left| {AgBr\left( s \right)\,\left| {B{r^ - }\left( {0.01\,M} \right)} \right|\,\left| {{I^ - }\left( {0.02\,M} \right)} \right|\,AgI\left( s \right)} \right|Ag\left( s \right)$
the correct information is
[Given : $K_{sp}\,\left( {AgBr} \right) = 4 \times {10^{ - 13}}$ ,
$K_{sp}\,\left( {AgI} \right)$ $ = 8 \times {10^{ - 17}},\frac{{2.303\,RT}}{F} = 0.06\,V,\,\log \,2 = 0.3]$
$2MnO_4^-+ 10I^-+ 16H^+ \to 2Mn^{2+} + 5I_2 + 8 H_2O$
The rate of apperance of $I_2$ is

