Chemistry 11 past paper 2022

Number of atoms of oxygen present in $500\text{ g}$ of $KClO_3$ is (M.Wt: $K=39, Cl=35.5, O=16$):

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The number of hydrogen molecules required to form 36 g of water (H₂O): 2H₂ + O₂ → 2H₂O

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The liquid $CHBr_3$ has a density of $2.89\text{ g/cm}^3$. What volume of this liquid should be measured to contain a total of $4.8 \times 10^{24}$ molecules of $CHBr_3$? (M.Wt: $C…

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Consider the reaction $CH_4 + H_2O \rightarrow CO + 3H_2$. (i) What is the amount of $CO$ produced if $30\text{ g}$ of $CH_4$ and $50\text{ g}$ of $H_2O$ is used? (ii) In an experi…

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Magnesium reacts with Sulphur to produce $MgS$. How many grams of $MgS$ can be made from $24\text{ g}$ of $Mg$ with excess of Sulphur by the reaction $Mg + S \rightarrow MgS$? (M.W…

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The values of Balmer series wave number lines lie in:

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Point out the three defects of Bohr's model.

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Describe the construction of a lead storage battery and the reactions taking place during charging and discharging.

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Which of the following is **NOT** a state function?

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Which of the following sets of quantum numbers is incorrect for an electron?

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How does **dipole moment** help to determine the polarity of molecules? Apply this concept to determine the nature of $CO_2$ and *cis*-1,2-dichloroethene.

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What is **orbital hybridization**? Explain the structure of $HC \equiv CH$, $BF_3$, and $CH_4$ on the basis of hybridization.

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If frequency of Photon is $4 \times 10^{15}\text{ Hz}$, then its energy will be: ($h = 6.626 \times 10^{-34}\text{ Js}$)

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Hybridization of beryllium in $BeCl_2$ will be:

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Predict and draw the shape and bond angles of the following molecules on the basis of **VSEPR theory**: (i) $H_2S$ (ii) $SnCl_2$ (iii) $PCl_3$

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State **Le-Chatelier's principle**. Briefly discuss the effect of increase in pressure, increase in concentration of $SO_2$, increase in temperature, and increase in $NO_2$ catalys…

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According to Moseley's law, when metals having large atomic number are used as an anode, they will produce X-rays of:

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Which one of the following gas molecules will only show translational motion?

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Briefly explain **azimuthal quantum number**. How does it help to determine the number of electrons in a subshell?

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Draw the complete **Born-Haber cycle** for the formation of $MgO$ from the following data: $\Delta H_f^0$ of $MgO = -602\text{ kJ/mol}$, $\Delta H_s^0$ of $Mg = 150\text{ kJ/mol}$,…

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Total number of **Sigma** and **Pi** bonds in Ethyne ($CH \equiv CH$) are:

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According to **Graham's Law of Diffusion**, the rate of diffusion ($v$) is related to mass ($m$) as:

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Why does the addition of solute increase the boiling point of a solution? Explain the quantitative aspects of elevation of boiling point and prove that $\Delta T_b$ is inversely pr…

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Identify the species with **maximum** bond angle:

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**Osmotic pressure** ($\pi$) does NOT depend on:

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How can the **molar mass** and **density** of a gas be determined with the help of the general gas equation?

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In lead storage battery, the electrolyte is:

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Equilibrium constants $K_c = K_p$, when $\Delta n$ is:

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Why is **butane** a gas at room temperature while **hexane** is a liquid?

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According to **Le Chatelier's Principle**, in an exothermic reaction, what should be done to the temperature of the system to obtain maximum product at equilibrium?

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$K_a$ is acid association constant; a large $pK_a$ value for an acid indicates that the acid is:

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Differentiate between **Isomorphism** and **Polymorphism** with suitable examples.

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According to **Graham's law**, which one has the highest rate of diffusion? (M.Wt: $S=32, O=16, H=1$)

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Which of the following is an **acidic salt**?

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Describe **electron sea theory**. How does it explain the properties of metals?

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Rate of reaction is independent of the concentration of reactants in:

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For the reaction $N_2 + 3H_2 \rightleftharpoons 2NH_3$ with $K_c = 6 \times 10^{-1}$ at $500^{\circ}C$, predict the direction in which the system will shift to attain equilibrium w…

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Which one is a conductor but not malleable?

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Which of the following gases will be most **non-ideal** at $-10^{\circ}C$?

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Calculate the **pH** of a buffer when molar concentrations of $NH_4OH$ and $NH_4Cl$ are $1.0\text{ M}$ and $0.1\text{ M}$ respectively. $pK_b$ of $NH_4OH$ is $4.75$.

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Which of the following concentration units does **NOT** depend on temperature?

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$\Delta H = \Delta E + P\Delta V$ is the formula for:

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Explain with chemical equations why aqueous solutions of: (i) $NH_4Cl$ is acidic (ii) $K_2CO_3$ is basic (iii) $Na_2SO_4$ is neutral.

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Which of the following will contain the **lowest** vapor pressure at $50^{\circ}C$?

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Which of the following relationships is **incorrect**?

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Consider the reaction $2H_2 + 2NO \rightarrow N_2 + 2H_2O$ with rate law $R = K[H_2][NO]^2$. If this reaction occurs in two steps, write its mechanism and predict the reaction inte…

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A solution of $HCl$ having $pH = 4$ will be:

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Oxidation state of O in KO₂ is:

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What is **diffusion**? Also state **Graham's law** of effusion and diffusion with its mathematical expression.

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$K_c = 0.04$ at $723\text{ K}$ for the following reaction: $PCl_{5(g)} \rightleftharpoons PCl_{3(g)} + Cl_{2(g)}$. The $K_p$ of the reaction will be: (where $R = 0.082\text{ atm dm…

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Which of the following has the **strongest intermolecular forces** of attraction?

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Calculate the **molality** of a $30\% \frac{w}{w}$ solution of fructose ($C_6H_{12}O_6$).

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In a mixture containing 44 g each of CO₂, SO₂, SO₃ and Cl₂ gases, which of the following will have the highest partial pressure according to Dalton's Law? (Molar masses: CO₂=44, SO…

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Lattice energy may also be called:

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Define **system**, **surroundings**, and **boundary** with a suitable example.

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Predict the feasibility of the following reaction: $Sn + Mg^{2+} \rightarrow Sn^{2+} + Mg$ given $E^{\circ}_{Sn} = -0.14\text{ V}$ and $E^{\circ}_{Mg} = -2.38\text{ V}$.

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**Distillation under reduced pressure** is often used for purification of sensitive liquids. Describe the process giving reasons.

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Apply the **$n+l$ rule** and pick the orbital with the lower energy from each of the given pairs: (i) $3d, 4s$ (ii) $2p, 3s$ (iii) $6p, 4s$.

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