2. Sample Papers
  3. KVPY

KVPY Sample Paper KVPY Stream-SX Model Paper-25

  • question_answer
    A mixture of 100 m mol of \[Ca{{(OH)}_{2}}\]sodium sulphate dissolved in water and the volume was made up to 100 mL. The mass of calcium sulphate formed and .the concentration of OH~ in resulting solution, respectively are (Molar mass of \[Ca{{(OH)}_{2}},\]\[N{{a}_{2}}S{{O}_{4}}\]and \[CaS{{O}_{4}}\]are 74, 143 and 136 g \[mo{{l}^{-1}}\] respectively \[{{K}_{sp}}\] of \[Ca{{(OH)}_{2}}\]is \[5.5\times {{10}^{-6}}\])

    A) 1.9 g, \[0.28\,mol\,{{L}^{-1}}\]

    B) 13.6 g, \[0.28\,mol\,{{L}^{-1}}\]

    C) 1.9 g, \[0.14\,mol\,{{L}^{-1}}\]

    D) 13.6 g, \[0.14\,mol\,{{L}^{-1}}\]

    Correct Answer: A

    Solution :

    \[\underset{-}{\mathop{\underset{100\,m\,mol}{\mathop{Ca{{(OH)}_{2}}}}\,}}\,+\underset{-}{\mathop{\underset{14\,m\,mol}{\mathop{N{{a}_{2}}S{{O}_{2}}}}\,}}\,\xrightarrow[{}]{{}}\underset{14\,m\,mol}{\mathop{\underset{{}}{\mathop{CaS{{O}_{4}}}}\,}}\,+\underset{28\,m\,mol}{\mathop{\underset{{}}{\mathop{2NaOH}}\,}}\,\]
    \[{{W}_{CaS{{O}_{4}}}}=14\times {{10}^{-3}}\times 136=1.9gm\]
    \[[O{{H}^{-}}]=\frac{28}{100}=0.28M.\]


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