EAMCET Medical EAMCET Medical Solved Paper-2009

  • question_answer
    The volume of oxygen gas liberated at \[27{{\,}^{o}}C\] and 760 mm Hg pressure when 24.5 g of \[\text{KCl}{{\text{O}}_{\text{3}}}\] is heated, is \[\text{(M}\text{.wt}\text{.of KC1}{{\text{O}}_{\text{3}}}\text{=122}\text{.5)}\]

    A)  4.48 L                                   

    B)  9.6 L

    C)   7.4 L                                    

    D)  11.2 L

    Correct Answer: C

    Solution :

                     \[\begin{align}   & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\underset{\begin{smallmatrix}  2\times 122.5 \\  =\,245.0 \end{smallmatrix}}{\mathop{KCl{{O}_{3}}}}\,\xrightarrow{{}}\underset{\begin{smallmatrix}  3\,\,\times \,22.4 \\  =\,\,67.2L \end{smallmatrix}}{\mathop{2KCl+3{{O}_{2}}}}\, \\  & at\,STP\,\,\,\,\,\,\,\,\, \\ \end{align}\] \[\because \]When \[245\,g\,KCl{{O}_{3}}\]is heated, liberated oxygen = 67.2 L \[\therefore \] When \[24.5\text{ }g\text{ }KCl{{O}_{3}}\] is heated, liberated oxygen \[=\frac{67.2\times 24.5}{245}=6.72\,L\] This volume of oxygen was liberated at STP. Therefore, at \[{{27}^{o}}C\]and 760 mm Hg pressure, the volume of liberated oxygen will be (STP) (Given conditions) \[\frac{{{p}_{1}}{{V}_{1}}}{{{T}_{1}}}=\frac{{{p}_{2}}{{V}_{2}}}{{{T}_{2}}}\] \[\frac{760\times 6.72}{273}=\frac{760\times {{V}_{2}}}{300}\] \[\therefore \]  \[{{V}_{2}}=\frac{760\times 6.72\times 300}{760\times 273}\]                 \[\text{=}\,\text{7}\text{.38}\,\text{L}\]\[\approx \,\text{7}\text{.4}\,\text{L}\]


You need to login to perform this action.
You will be redirected in 3 sec spinner