Chemistry 11 past paper 2024

A liquid is thought to be pure ethanol. Which of the following is the best way to test its purity?

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Calculate the volume of oxygen produced by decomposition of $3.04 \times 10^{24}$ formula units of $KClO_3$ according to the given equation: $2KClO_3 \rightarrow 2KCl + 3O_2$

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What is hybridization? Explain the hybridization of $CH_4$ and $BeCl_2$ with orbital diagrams.

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Volume occupied by $2\text{ g}$ of $SO_2$ gas at S.T.P will be:

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Calculate the wave number ($\bar{\nu}$) of $H_\alpha$ in Balmer series and second line in Paschen series of hydrogen spectrum.

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Why do real gases deviate from gas laws at low temperature and high pressure? Also explain the deviation by general graphical representation of compressibility factor versus pressu…

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The largest/maximum number of molecules are present in:

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In an industrial process 40 g of H₂ produces 100 g of NH₃. Calculate the percentage yield of this reaction: N₂ + 3H₂ → 2NH₃

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State first law of thermodynamics. Write its mathematical expression with reference to heat and work. Explain it for a gas confined to a cylinder having a moveable piston, and deri…

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Justify the following statements with reference to azimuthal quantum number: (i) s-orbital has maximum two e⁻ (ii) p-orbital can accommodate maximum six electrons.

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Balance the given redox equations by oxidation number method: (i) $HNO_3 + H_2S \rightarrow NO + S + H_2O$ (ii) $P + H_2O + HNO_3 \rightarrow H_3PO_4 + NO$.

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The third line of Balmer series appears due to the transition of electron from:

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Calculate the number of molecules of $SO_2$ gas if its volume is $500\text{ cm}^3$ at S.T.P.

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What is buffer solution? Write its types with composition. Explain buffer action when small amount of base is added in it.

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Which of the following covalent bond has lowest bond energy?

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Why is CO₂ linear while H₂O is bent or V-shaped, although the atomicity of both molecules is the same?

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What are colligative properties of solutions? Explain quantitative aspects of freezing point depression with general graphical representation to derive the molar mass of solute.

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Shape of $PH_3$ molecule is:

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Calculate the number of molecules of $CO_2$ when $4.8 \times 10^{24}$ molecules of $CH_4$ reacts with excess of water according to the following reaction: $CH_4 + 2H_2O \rightarrow…

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What are London dispersion forces? Explain any three factors which affect these forces with suitable example in each factor.

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Which pair of gases diffuses with the same rate at same temperature and pressure?

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Draw the shapes of following molecules according to VSEPR theory: (i) $SO_2$ (ii) $H_2S$ (iii) $CBr_4$

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Differentiate between cubic close packing and hexagonal close packing in metals. Also compare metallic solids with molecular solids in three ways.

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Which of the following is **NOT** present in plasma?

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Briefly describe the following: (i) Line spectrum (ii) Stark effect (iii) Continuous spectrum

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Which of the following processes is **NOT** endothermic?

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Distinguish between **Sigma** and **Pi bond** in three ways.

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If crystallization of **NaCl** is carried out in the presence of urea then its shape will be:

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Calculate the average molar mass of air at sea level at $0^\circ C$, if density of air is $1.29\text{ kg/m}^3$.

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The strong conjugate base among the given options is:

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Justify the following statements: (i) Petrol evaporates earlier than water (ii) Water has lower vapour pressure than ethyl alcohol.

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A reaction will proceed in forward direction to maximum extent if value of $K_c$ is:

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What is the effect on the volume of gas if you simultaneously: (i) Its pressure is halved and its kelvin temperature is doubled (ii) Its pressure is doubled and its kelvin temperat…

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For a reaction $A \rightarrow \text{Product}$, doubling the concentration of **A** quadruples the rate. The reaction is:

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Why heat of vaporization ($\Delta H_v$) is always greater than heat of fusion ($\Delta H_f$) for a substance?

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Swelling of dead bones in water is due to:

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Calculate the numerical value of general gas constant **R** for one mole of gas at S.T.P: (i) In SI units (ii) Pressure in atm, volume in $dm^3$.

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

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Write any three characteristics of Plasma.

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**Zn** acts as anode in Daniel cell but acts as cathode in Al-Zn cell because:

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Predict the shape of ZnS by using formula of radius ratio, if radius of Zn²⁺ is 74 pm and radius of S²⁻ is 184 pm.

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If initial concentration of $N_2O_4$ in moles is **a** and **x** moles of it converted to $NO_2$, then derive the general relation of equilibrium constant ($K_c = \frac{4x^2}{V(a-x…

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Calculate the value of $K_p$ at $1050^\circ C$ if $K_c$ is $2.3 \times 10^{22}$ for the following reaction: $2CO_{(g)} + O_{2(g)} \rightleftharpoons 2CO_{2(g)}$.

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Write $K_{sp}$ expressions for following compounds: (i) $Ca_3(PO_4)_2$ (ii) $Na_2SO_4$.

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What is levelling effect of water? How this effect is compensated?

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Draw potential energy diagram for both exothermic and endothermic reactions according to collision theory.

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Rate equation for given reaction is $R = K[NO]^2[H_2]$. Reaction occurs in two steps and oxygen atom is intermediate then write reaction mechanism: $2NO + 2H_2 \rightarrow N_2 + 2H…

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How relative lowering of vapour pressure ($\frac{\Delta P}{P^\circ} = X_2$) can be used to calculate molar mass of solute?

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Describe phenol water system and explain upper consulate temperature.

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Write thermochemical equations from the given information: (i) Standard enthalpy of formation of $CaCO_3$ is $-1207\text{ kJ/mol}$ (ii) Standard enthalpy of combustion of $CH_3COOH…

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Calculate $E^\circ_{\text{cell}}$ for Li-Zn cell and write cell reactions. $E^\circ_{\text{Li}}$ is $-3.05\text{ V}$ and $E^\circ_{\text{Zn}}$ is $-0.76\text{ V}$.

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Write chemical reactions that occur at cathode and anode in alkaline dry cell.

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