Chemistry Model set 1 shaalaa.com 2021-2022 HSC Science (General) 12th Standard Board Exam Question Paper Solution

The colligative properties of solutions _______.

depend on nature of solute particles

do not depend on number of solute particles

do not depend on dissociation of solute in solvent

depend on number of solute particles

The following electronic configuration of elements shows highest oxidation state

3d⁵4s²

3d⁵4s¹

3d¹⁰4s²

3d¹⁰4s¹

Hot and concentrated alkali NaOH reacts with chlorine to form _______.

only chlorate

only hypochlorite

chloride and chlorate

chloride and hypochlorite

Correct order of acid strength for

1. acetic acid
2. fluoroacetic acid
3. 4-Nitrobenzoic acid 
4. 4-Methyl benzoic acid is ______.

i > ii > iii > iv

ii > iii > iv > i

iii > iv > i > ii

iv > i > ii > iii

The IUPAC name of Na₃[AlF₆] is _____________

Hexa fluorosodiumaluminate

Sodium hexafluoroaluminate(III)

Sodium hexafluoroaluminate(II)

Sodium hexafluoroaluminium(III)

The type of mono halogen derivative in which a halogen atom is bonded to sp³ hybridized carbon atom next to carbon-carbon double bond is ______________

alkyl halide

allylic halide

vinylic halide

benzylic halide

Bottom ash of thermal power stations can be used as raw material for cement and brick industry. This example illustrates which of the following principle of green chemistry?

Atom economy.

Designing safer chemicals.

Design for energy efficiency.

Prevention of waste or by products.

Chemical combination of Ziegler-Natta catalyst is ______________

trimethyl aluminium titanium tetrachloride

triethyl aluminium titanium tetrachloride

triethyl aluminium titanium trichloride

triethyl aluminium titanium dichloride

The work done in vacuum when 300 m mole of an ideal gas expands until its volume is increased by 2.3 dm³ at 1 bar pressure is ______ mole.

Zero

One

Two

Three

Sodium crystallizes in bcc structure. If the edge length of unit cell is 4.3 × 10^-8 cm, the radius of Na atom is ______.

1.86 × 10^-8 cm

1.52 × 10^-8 cm

2.15 × 10^-8 cm

4.3 × 10^-8 cm

Write an equation that shows the relationship between molar conductivity and degree of dissociation of weak electrolyte.

Nylon 6, 6 is a condensation polymer of hexamethylenediamine and _____________

picric acid

adipic acid

terephthalic acid

ε-caprolactam

Write IUPAC name of the product ‘B’ in the following reaction sequence.

\[\ce{C2H5OH ->[NaBr/H2SO4][\Delta] A ->[Nal][acetone]B}\]

Identify molecularity of following reaction:

\[\ce{C2H5I_{(g)} -> C2H_{4(g)} + HI_{(g)}}\]

Arrange the following in decreasing order of acid strength.

CH₃OH, CH₃–CH₂–OH, CH₃–CH(OH)–CH₃, (CH₃)₃–C–OH

Draw diagram of bcc unit cell.

Write the number of moles of ethanoyl chloride required for complete acylation of N, N-dimethylaniline.

Calculate effective atomic number of iron in [Fe(CN)₆]⁴⁻ complex ion

Explain globular and fibrous proteins with example.

Elements of group 16 have lower ionization enthalpy values compared to those of group 15 elements. Explain why?

Write applications of Kohlrausch’s Law.

Explain homoleptic and heteroleptic complexes.

Give reason. Though alkyl halides are moderately polar, they are insoluble in water.

Distinguish between ideal and non-ideal solutions.

Define molar solubility. Write it’s unit.

Write chemical equation of acetyl chloride with ethanol

Draw structure of following.

2-Deoxy-D-ribose

Write preparation of low density polythene.

What is half life of first order reaction if time required to decrease concentration of reactants from 0.8 M to 0.2 M is 12 hours?

What is the mass of copper metal produced at cathode during the passage of 2.03 A current through the CuSO₄ solution for 1 hour. Molar mass of Cu = 63.5 g mol^–1.

Distinguish between methanamine, dimethanamine and trimethanamine using Hinsberg’s reagent.

Explain any three characteristic features of nanoparticles.

Write any two uses of actinides.

Discuss industrial method of preparation of sulfur dioxide from zinc sulfide and iron pyrites.

Write a reaction to distinguish acetaldehyde from acetone

Explain the magnetic properties of [Ni(CN₄)]^2–.

An organic compound A with molecular formula C₄H₁₀O on treatment with phosphorus pentachloride gives alkyl chloride. Alkyl chloride on treatment with Mg in presence of dry ether gives a highly reactive compound B.
Compound B reacts with water to give hydrocarbon C. Alkyl chloride on treatment with Na in dry ether as a solvent gives alkane, 2,2,3,3-tetramethylbutane. Identify ‘A’, ‘B’, ‘C’

Explain the osmotic pressure of a solution with the help of a thistle tube.

A reaction occurs in the following steps:

Step 1: \[\ce{NO_{2(g)} + F_2 -> NO2F_{(g)} + F_{(g)}}\] (slow)

Step 2: \[\ce{F_{(g)} + NO_{2(g)} -> NO_2F}\] (Fast)

1. Write the equation of overall reaction.
2. Write the rate law.
3. Identify reaction intermediate.

Write the preparation of ethanol from methyl magnesium iodide.

A substance crystallizes in fcc structure. The unit cell edge length is 367.8 pm. Calculate the molar mass of the substance if its density is 21.5 g/cm³.

Three moles of an ideal gas are expanded isothermally from 15 dm³ to 20 dm³ at a constant external pressure of 1.2 bar, calculate the amount of work in Joules.

Write an application of Hess’s law.

Explain the acidic nature of carboxylic acids.

Answer the following

Explain the trends in atomic radii of d block elements.

Explain the amphoteric nature of water.

Describe the manufacturing of H₂SO₄ by the contact process.

Calculate molar conductivities at zero concentration for CaCl₂ and NaCl.

Given: molar ionic conductivities of Ca²⁺, Cl^–, Na⁺ ions are respectively, 104, 76.4, 50.1 Ω–1 cm^–2 mol^–1