🧪 Class Test – Chapters: Solutions, Electrochemistry & Chemical Kinetics

 

🧪 Class Test – Chapters: Solutions, Electrochemistry & Chemical Kinetics

Total Questions: 10

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Q1.
A solution is prepared by dissolving 5.85 g of NaCl in 100 g of water. Calculate the lowering in vapour pressure of water if the vapour pressure of pure water at 298 K is 23.8 mm Hg.
(Molar mass of NaCl = 58.5 g/mol; assume complete dissociation)

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Q2.
Calculate the standard cell potential for the following cell reaction:
$Zn(s) + Cu^{2+}(aq) \rightarrow Zn^{2+}(aq) + Cu(s)$
Given:
$E_{Z{n}^{2+}\mathrm{/}Zn}^{\circ }=-0.76\text{ V},E_{C{u}^{2+}\mathrm{/}Cu}^{\circ }=+0.34\text{ V<span class="base"><br></span>}$

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Q3.
For a reaction, the rate law is given by:
$\text{Rate} = k[A]^2[B]$
What is the order of the reaction? If the concentration of A is doubled and B is halved, by what factor will the rate change?

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Q4.
Define Van’t Hoff factor. How does it help in determining the degree of dissociation of an electrolyte?

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Q5.
The decomposition of NH₃ on a platinum surface is a zero-order reaction.
(i) What are the units of the rate constant?
(ii) Write the rate law for this reaction.

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Q6.
A solution of glucose (C₆H₁₂O₆) is prepared by dissolving 18 g in 100 g of water. Calculate the relative lowering in vapour pressure.
(Molar mass of glucose = 180 g/mol)

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Q7.
Calculate the standard cell potential for the reaction:
$Fe(s) + Cu^{2+}(aq) \rightarrow Fe^{2+}(aq) + Cu(s)$
Given:
$E^\circ_{Fe^{2+}/Fe} = -0.44 \text{ V},\quad E^\circ_{Cu^{2+}/Cu} = +0.34 \text{ V}$

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Q8.
For a reaction, the rate law is:
$\text{Rate}=k[A][B{]}^2$.  What is the order of the reaction? If [A] is doubled and [B] is doubled, how many times will the rate increase?

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Q9.
What do you understand by the term abnormal molar mass? How does the Van’t Hoff factor help in calculating it?

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Q10.
The thermal decomposition of hydrogen peroxide (H₂O₂) follows first-order kinetics.
(i) What are the units of the rate constant?
(ii) Write the rate law expression for the reaction.

ANSWERS

LEVEL1 WORKSHEET SOLUTION

LEVEL 2 WORKSHEET SOLUTION