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Chemistry 11 Past Paper 2023 | Notely

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All Chemistry 11 papers

Class 11 · Past paper

Chemistry 11 past paper 2023

41 published questions in this index. The full practice view lets you work through them and track your own attempts.

15 MCQs26 written questionsPractise this paper

Question index

1
The volume occupied by $3.01 \times 10^{23}$ molecules of $NH_3$ gas at **STP** is:
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1
Calculate the mass of $NH_3$ gas produced when $8 dm^3$ of $H_2$ gas is reacted with excess of $N_2$ gas: $N_2 + 3H_2 \rightarrow 2NH_3$
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1
$100 \text{ g}$ $Zn$ is reacted with $100 \text{ g}$ solution of $HCl$: $Zn + 2HCl \rightarrow ZnCl_2 + H_2$. (i) How much volume of $H_2$ gas is released at STP? (ii) Also determi…
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2
Lyman series of spectral lines lies in which of the following region of electromagnetic spectrum?

This is a skimmable index, not a replacement for the study surface. Open the practice view to answer questions and use the linked study material.

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2

How much energy is required to remove an electron from the 1st orbit of Li²⁺ ion in the units of J/atom and kJ/mol?

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2

Derive a relationship for energy released ($\Delta E$) when an electron drops from $n_2$ orbit to $n_1$ orbit in $He^+$ ion. Also calculate $\Delta E$ if $n_1=1$ and $n_2=3$ in $He…

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3

Which of the following molecules does **not** possess trigonal planar geometry?

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3

Write down the disadvantages of valence bond theory.

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3

What is **salt hydrolysis**? Which type of cations and anions undergo hydrolysis? Describe the hydrolysis of four types of salts giving one example for each.

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4

Which of the following aromatic compounds has **zero dipole moment**?

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4

Describe any two factors which affect bond length. Give one example for each.

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4

What is **collision theory**? Describe with reference to the energy of activation, formation of activated complex and heat of reaction.

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5

The value of general gas constant $R$ is $62.4$. Its units are:

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5

Describe the geometries of following molecules on the basis of **VSEPR theory**: (a) $SO_3$ (b) $PCl_3$

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5

State and explain Dalton's law of partial pressure. Derive a relationship between: (i) Partial pressure and number of moles (ii) Partial pressure and mole fraction.

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6

Rate of diffusion of $H_2$ gas ($r_{H_2}$) as compared to that of $He$ gas ($r_{He}$) is:

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6

What is an **Isobar**? Draw an isobar for a given mass of an ideal gas at 1 atm. How does the position of isobar change with increase in pressure?

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6

Describe the effect of stated change on the following reactions at equilibrium position: (i) Decreasing the volume in $2NO + O_2 \rightleftharpoons 2NO_2$ (ii) Increasing temperatu…

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7

At $145^{\circ}C$, **Cholesteryl Benzoate** exists as:

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7

How are **London dispersion forces** developed in a sample of Helium gas?

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8

The increase in boiling point of hydrides of group IV-A ($CH_4$ to $SnH_4$) is due to increase in the strength of:

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8

Which substance in each of the following pairs has stronger London dispersion forces? Give reasons: (a) Ar or Kr (b) Br₂ or I₂ (c) C₂H₆ or C₄H₁₀

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9

Which of the following is **NOT** an anisotropic property?

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9

What is the role of **hydrogen bonding** in: (a) Cleansing action of soap (b) Structure of DNA and protein molecules

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10

Identify the pair of substances which are **not isomorphs**?

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10

Describe **transition temperature** by giving two examples.

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11

The value of $K_p$ will become equal to $K_c$, $K_x$ and $K_n$, when:

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11

Differentiate between **Hexagonal close packing** and **cubic close packing** in the structure of metals.

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12

What is a **precipitation reaction**? How can one predict the formation of precipitates of $CaF_2$ in the following reaction? $Ca^{+2} + 2F^- \rightleftharpoons CaF_2$

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13

For which of the following reaction, the **rate constant** is equal to the **rate of reaction**?

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13

How does an acetic acid/sodium acetate buffer resist change in pH on addition of NaOH?

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14

Boiling point of a solution prepared by dissolving 18 g glucose in 1 kg water is (Kb = 0.52):

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14

Why does the vapour pressure of a solvent decrease when a non-volatile, non-electrolyte solute is dissolved in it?

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15

A colloid in which a liquid is dispersed into another liquid is called:

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15

What is **reverse osmosis**? Give its one application.

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16

Heat capacity of a substance is measured in the units of:

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16

If conc. of $O_3$ in the atmosphere reaches $0.5$ ppb, what mass of $O_3$ would be present per kg of the air?

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17

Calculate $\Delta H^{\circ}$ for the following reaction: $2C_8H_{18} + 25O_2 \rightarrow 16CO_2 + 18H_2O$. The values of $\Delta H_f^{\circ}$ for $C_8H_{18}$, $O_2$, $CO_2$ and $H_…

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18

When $1.8 \text{ g}$ glucose is burnt in a bomb calorimeter, the temperature of water increases from $25^{\circ}C$ to $31.52^{\circ}C$. If the heat capacity of the calorimeter is $…

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19

Predict $E^{\circ}_{cell}$ for $Zn-Ni$ cell and write its cell reactions. The values of reduction potential of $Zn$ and $Ni$ are: $E^{\circ}_{Zn} = -0.76 V$ and $E^{\circ}_{Ni} = -…

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20

Balance the equation by **ion-electron method**: $BrO_3^{-} + SO_2 \rightarrow HSO_4^{-} + Br^{-}$

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