Chemistry Set 1 2021-2022 HSC Science (General) 12th Standard Board Exam Question Paper Solution

The coordination number of atoms in body-centred cubic structure (bcc) is ______.

4

6

8

12

Choose the most correct option.

In calculating osmotic pressure the concentration of solute is expressed in _______.

molarity

molality

mole fraction

mass percent

The enthalpy change for the chemical reaction \[\ce{H2O_{(s)} -> H2O_{(l)}}\] is called enthalpy of ______.

vapourisation

fusion

combustion

sublimation

Which of the following transition element shows maximum oxidation state?

Sc

Fe

Mn

V

The correct formula for the complex compound, sodium hexacyanoferrate (III) is ______.

Na [Fe(CN)₆]

Na₂ [Fe(CN)₆]

Na₃ [Fe(CN)₆]

Na₄ [Fe(CN)₆]

[NaFe(CN)₆]

Isopropylbenzene on air oxidation followed by decomposition by dilute acid gives ______.

C₆H₅OH

C₆H₅COOCH₃

C₆H₅COOH

C₆H₅CHO

The name of metal nanoparticle which acts as highly effective bacterial disinfectant in water purification process is ______.

carbon black

silver

gold

copper

Acid anhydride on reaction with primary amine gives compound having a functional group ______.

amide

nitrile

secondary amine

imine

The standard potential of the cell in the following reaction is ______.

\[\ce{Cd_{(s)} + Cu^{2+}_{(1M)} -> Cd^{2+}_{(1M)} + Cu_{(s)}}\]

`("E"_("Cd")^circ = - 0.403V, "E"_("Cu")^circ = 0.334V)`

– 0.737 V

0.737 V

– 0.069 V

0.069 V

The value of [H₃O⁺] in mol lit^–1 of 0.001 M acetic acid solution (K_a = 1.8 × 10^–5) is ______.

1.34 × 10^–1

1.34 × 10^–2

1.34 × 10^–3

1.34 × 10^–4

Write the product formed when alkyl halide reacts with silver nitrite.

Write the name of product formed, when acetone is treated with 2, 4-dinitrophenyl hydrazine.

Write the name of biodegradable polyamide copolymer.

Identify the molecularity of following elementary reaction:

NO_(g) + O_3(g) → NO_3(g) + O_(g)

What is the action of selenium on magnesium metal?

Write the name of isomerism in the following complexes:

[Cu(NH₃)₄] [PtCl₄] and [Pt(NH₃)₄] [ CuCl₄]

Write the name of the alloy used in the Fischer Tropsch process in the synthesis of gasoline.

Henry's law constant for CH₃Br_(g) is 0.159 mol dm^–3 bar^–1 at 25°C. What is the solubility of CH₃Br_(g) in water at the same temperature and partial pressure of 0.164 bar?

Explain pseudo first order reaction with a suitable example.

Write the consequences of Schottky defect with reasons.

What is the action of following on ethyl bromide:

Na in dry ether

What is the action of following on ethyl bromide?

\[\ce{Mg}\] in dry ether

Explain formation of peptide linkage in protein with an example.

Derive an expression to calculate molar mass of non-volatile solute by osmotic pressure measurement.

Explain monodentate and ambidentate ligands with example.

Explain the trends in the following atomic properties of group 16 elements:

Atomic radii

Explain the trends in the following atomic properties of group 16 elements:

Ionisation enthalpy

Explain the trends in the following atomic properties of group 16 elements:

Electronegativity

Explain the trends in the following atomic properties of group 16 elements:

Electron gain enthalpy

Write preparation of phenol from aniline.

Write chemical reactions to prepare ethanamine from:

Acetonitrile

Write chemical reactions to prepare ethanamine from:

Nitroethane

Identify A and B from the following reaction:

\[\begin{array}{cc}
\ce{CH3}\phantom{.................}\\
|\phantom{....................}\\
\phantom{}\ce{2CH3 - C = O ->[Ba(OH)2] A ->[Δ] B + H2O}
\end{array}\]

One mole of an ideal gas is expanded isothermally and reversibly from 10 L to 15 L at 300 K. Calculate the work done in the process.

How many moles of electrons are required for reduction of 2 moles of Zn²⁺ to Zn? How many Faradays of electricity will be required?

Write chemical composition of haematite. Write the names and electronic configurations of first two elements of group 17.

Write classification of polymers on the basis of structure.

Define Green chemistry.

Write two disadvantages of nanotechnology.

Write a commercial method for preparation of glucose.

Write structure of adipic acid.

Write chemical reactions of following reagents on methoxyethane:

hot HI

Write chemical reactions of following reagents on methoxyethane:

PCl₅

Write chemical reactions of following reagents on methoxyethane:

dilute H₂SO₄

Explain cationic, anionic and neutral sphere complexes w ith example.

Calculate spin only magnetic moment of divalent cation of transition metal with atomic number 25.

Salts of Ti⁴⁺ are colourless. Give reason.

What is Lanthanoid contraction?

Write preparation of acetic acid from:

dry ice

Write preparation of acetic acid from:

acetyl chloride

Write a classification of aliphatic ketones with a suitable example.

What is the action of sodium hypoiodite on acetone?

Define the half-life of a first-order reaction.

Obtain the expression for half-life and rate constant of the first-order reaction.

Calculate the standard enthalpy of formation of CH₃OH_(l) from the following data:

1. \[\ce{CH3OH_{(l)} + 3/2 O2_{(g)} -> CO2_{(g)} + 2H2O_{(l)}ΔH^° = - 726 kJ mol^{-1}}\]
2. \[\ce{C_{(s)} + O2_{(g)} → CO2_{(g)}Δ_cH^° = – 393 kJ mol^{-1}}\]
3. \[\ce{H2_{(g)} + 1/2 O2_{(g)} -> H2O_{(l)}Δ_fH^° = - 286 kJ mol^{-1}}\]

Calculate the pH of buffer solution composed of 0.01 M weak base BOH and 0.02 M of its salt BA. [K_b = 1.8 × 10^–5 for weak base]

Define the following term:
isotonic solution

Explain the term osmosis.

Gold crystallises into face-centred cubic cells. The edge length of a unit cell is 4.08 × 10^–8 cm. Calculate the density of gold. [Molar mass of gold = 197 g mol^–1]

Write the mathematical equation for the first law of thermodynamics for:

Isothermal process

Write the mathematical equation for the first law of thermodynamics for:

Adiabatic process

Derive the relationship between pH and pOH.

Define Reference electrode

Answer the following in one or two sentences.

Write any two functions of salt bridge.

Draw a neat, labelled diagram of a standard hydrogen electrode (SHE).

Explain metal deficiency defect with examples.

Write the chemical equation for the preparation of sulphur dioxide from sulphur.

Write uses of sulphur.

Write chemical reactions for the following conversions:

Ethyl bromide to ethyl methyl ether.

Write chemical reactions for the following conversions:

Ethyl bromide to ethene.

Write chemical reactions for the following conversions:

Bromobenzene to toluene.

Write chemical reactions for the following conversions:

Chlorobenzene to biphenyl.