Three vessels \((A, B, C)\) contain \(\mathrm{H}_2 \mathrm{O}_2\) solution. In vessel \(A, 500…

Three vessels \((A, B, C)\) contain \(\mathrm{H}_2 \mathrm{O}_2\) solution. In vessel \(A, 500 \mathrm{~mL}\) of \(10 \mathrm{vol} \mathrm{H}_2 \mathrm{O}_2\) is present. \(100 \mathrm{~mL}\) of \(30 \mathrm{vol} \mathrm{H}_2 \mathrm{O}_2\) is present in vessel \(B\). Vessel \(C\) is filled with \(250 \mathrm{~mL}\) of \(2 \mathrm{M} \mathrm{H}_2 \mathrm{O}_2\). The weight (in \(\mathrm{g}\) ) of \(\mathrm{H}_2 \mathrm{O}_2\) present in these vessels follows the order
  1. \(C>A>B\)
  2. \(C>B>A\)
  3. \(B>A>C\)
  4. \(A>B>C\)

Solution

For vessel \(A\), \(10 \mathrm{vol} \mathrm{H}_2 \mathrm{O}_2\) means \(1 \mathrm{~mL}\) of \(\mathrm{H}_2 \mathrm{O}_2\) solution gives \(10 \mathrm{mLO}_2\). \(\begin{array}{cc}2 \mathrm{H}_2 \mathrm{O}_2 & \longrightarrow 2 \mathrm{H}_2 \mathrm{O}+\mathrm{O}_2 \\ 2 \mathrm{~mol} & 1 \mathrm{~mol} \\ =68 \mathrm{~g} & 22400 \mathrm{~mL} \text { at } \mathrm{NTP}\end{array}\) \(\therefore 22400 \mathrm{~mL}_2\) is obtained by \(68 \mathrm{~g} \mathrm{H}_2 \mathrm{O}_2\). \(\because 10 \mathrm{~mL} \mathrm{O}_2\) is obtained by \(\frac{68 \times 10}{22400}=0.03 \mathrm{~g} \mathrm{H}_2 \mathrm{O}_2\) Vessel \(B\), \(30 \mathrm{vol} \mathrm{H}_2 \mathrm{O}_2\) means \(1 \mathrm{~mL}\) of \(\mathrm{H}_2 \mathrm{O}_2\) solution gives \(30 \mathrm{mLO}_2\). Means, \(22400 \mathrm{~mL}\) of \(\mathrm{O}_2\) is obtained by \(68 \mathrm{~g} \mathrm{H}_2 \mathrm{O}_2\). \(\because 30 \mathrm{~mL} \mathrm{O}_2\) is obtained by \(\frac{68 \times 30}{22400}=0.09 \mathrm{~g} \mathrm{H}_2 \mathrm{O}_2\) Vessel \(C\), Given, it is filled with \(250 \mathrm{~mL}\) of \(2 \mathrm{M} \mathrm{H}_2 \mathrm{O}_2\). Molarity \(=\frac{\text { number of moles of } \mathrm{H}_2 \mathrm{O}_2}{\text { volume of sol in } \mathrm{L}}\) \(\therefore \quad 2=\frac{x / 34}{250 / 1000}\) or \(x=17 \mathrm{~g} \mathrm{H}_2 \mathrm{O}_2\) \(\therefore\) The weight (in g) of \(\mathrm{H}_2 \mathrm{O}_2\) present in vessels follows order : \(C > B > A\)

Asked in: AP EAMCET 2019 (23 Apr Shift 1)

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