2 Marks Questions

Question 12 Marks

Convert Toluene to m-Nitrobenzoic acid.

Question 22 Marks

a. Differentiate between Ideal solution and Non-ideal solution.
b. 30 g of urea is dissolved in 846 g of water. Calculate the vapour pressure of water for this solution if vapour pressure of pure water at 298 K is 23.8 mm Hg.

Answer

(a)

Ideal Solution	Non-ideal solution
The solution obeys Raoult's law at all concentrations.	The solution does not obey Raoult's law.
$\Delta V$ mixing $=0$ and $\Delta H_{\text {mixing }}=0$	$\Delta V _{\text {mixing }} \neq 0$ and $\Delta H _{\text {mixing }} \neq 0$

(b)
$
\frac{P_{A}^0-P_{A}}{P_{A^o}^o}=\frac{\frac{W_{B}}{M_{B}}}{\frac{W_{B}}{M_{B}}+\frac{W_{A}}{M_{A}}}
$$1-\frac{ P _{ A }}{23 \cdot 8}=\frac{\frac{30}{60}}{\frac{846}{18}}$ or $1-\frac{ P _{ A }}{23 \cdot 8}=\frac{\frac{30}{60}}{\frac{846}{18}+\frac{30}{60}}$
$P _{ A }=\frac{46.5}{47} \times 23.8=23.5 mm Hg$ or vapour pressure of the solution $P _{ A }=\frac{47}{47.5} \times 23.8=23.5 mm Hg$

View full question & answer→

Question 32 Marks

If the density of some lake water is $1.25 \ g mL^{-1}$ and contains $92 g$ of $Na^+$ ions per $\ kg$ of water, calculate the molarity of $Na^+$ ions in the lake.

Answer

$\text { Molar mass of } N a=23 \ g mol ^{-1}$
$\text { No. of moles of } Na ^{+}=\frac{92 g}{232 gmol -1}=4 mole$
$\text { Density }=\frac{\text { Mass }}{\text { Volume }}$
$V=\frac{\text { Mass }}{\text { density }}=\frac{1000}{1.25}(g)$
$V=800 ml$
$\text { Molarity }=\frac{\text { Number of moles }}{\text { Volume }( ml )} \times 1000$
$\text { Molarity }=\frac{4 \times 1000}{800}=5 moles $

View full question & answer→

Question 42 Marks

Answer the following:
$(a)$ The rate of a reaction is given by rate $= k [N_2O_5].$ In this equation what does k stand for?
$(b)$ Is it possible to determine or predict the rate law theoretically by merely looking at the equation?

Answer

Answer the following$:$
$(i) \ 'k \ '$ stands for rate constant of a reaction.
$(ii)$ The rate law is experimentally determined. It cannot be predicted by merely looking at the balanced chemical equation.

View full question & answer→

Question 52 Marks

Give reasons for the following:
$a.$ The only oxidation state shown by Scandium is $+3.$
$b. [Ti(H_2O)_6]^{4+}$ is colourless.
$c. MnO$ is basic while $Mn_2O_7$ is acidic.

Answer

$a. At + 3$ oxidation state, Stable $d^\circ$ is obtained
$b.$ Absence of unpaired electron / no $d-d$ transition occurs
$c. MnO$ has $Mn$ in $+2$ Oxidation State $Mn_2O_7$ has $Mn$ in $+7$ Oxidation State. Higher the Oxidation State, Higher is the acidic character.

View full question & answer→

Question 62 Marks

Write the formula of the following complexes:
$i.$ Hexaammine platinum $(IV)$ chloride.
$ii.$ Dichloro tetrammine cobalt $(III)$ ion.

Answer

$1. \ [Pt(NH_3)_6]Cl_4$
$2. \ [CoCl_2(NH_3)_4]^+$

View full question & answer→

Chemistry 2 Marks Questions

Test yourself on this topic