MCQ
The $pH$ at which $\mathrm{Mg}(\mathrm{OH})_2\left[\mathrm{~K}_{\mathrm{sp}}=1 \times 10^{-11}\right]$ begins to precipitate from a solution containing $0.10 \ \mathrm{M}$ $\mathrm{Mg}^{2+}$ ions is_____
  • A
    $08$
  • $09$
  • C
    $10$
  • D
    $11$

Answer

Correct option: B.
$09$
b
Precipitation when $Q_{s p}=K_{s p}$

${\left[\mathrm{Mg}^{2+}\right][\mathrm{OH}]^2=10^{-11}}$

$0.1 \times\left[\mathrm{OH}^{-}\right]^2=10^{-11} \Rightarrow\left[\mathrm{OH}^{-}\right]=10^{-5}$

$\Rightarrow \mathrm{pOH}=5 \quad \Rightarrow \mathrm{pH}=9$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

The ability of an atom in a chemical compound to attract shared electron is termed as :
Which of the following orders correctly depicts the decreasing order of stability of carbanion?
Who suggested the distribution of electrons into different orbits of an atom?
The compounds that will give an isomer of  $2; 2-$ dimethyl propane on catalytic hydrogenation are

$(1)$ $\begin{array}{*{20}{c}}
  {C{H_3}CH = C - C{H_3}} \\ 
  {\,\,\,\,\,\,\,\,\,\,|} \\ 
  {\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}} 
\end{array}$

$(2)$ $C{H_3}CH = CHC{H_3}$

$(3)$ $\mathop {C{H_3}C}\limits^{\begin{subarray}{l} 
  \,\,\,\,\,\,\,\,{\begin{array}{*{20}{c}}
  {}&H 
\end{array}} \\ 
  \,\,\,\,\,\,\,\,\,\,\,\,\,\,| 
\end{subarray} }  = CHC{H_2}C{H_3}$

$(4)$ $\begin{array}{*{20}{c}}
  {C{H_3}C = C - C{H_3}} \\ 
  {\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ 
  {\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_{3\,\,}}\,\,C{H_3}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} 
\end{array}$

A reaction attains equilibrium when the free energy change accompanying it is
The formula of oxide of an element $M$ having $IE_1 = 100\, kJ$, $IE_2 = 250\, kJ$ and $IE_3 = 1500\, kJ$ should be
To which of the following atom, the attachment of electron is most difficult?
If little heat is added to ice $\rightleftharpoons$ liquid, equilibrium in a sealed container, then :
Electrolytes are compound containing
In the lowest energy level of hydrogen atom, electron has an angular momentum equal to :