Maharashtra Board 2024 Class 12 Chemistry Question Paper (Available) :Download Solution PDF with Answer Key

Maharashtra Board Class 12 Chemistry Solution

SECTION-A

Question 1:

(i) The spin-only magnetic moment of Cr\(^{3+}\) cation is \underline{\hspace{1cm.

• (a) \(3.742 \) BM
• (b) \(3.755 \) BM
• (c) \(3.873 \) BM
• (D) \(3.633 \) BM

(ii) The linkage present in Lactose is \hspace{1cm}.

• (a) \(\alpha, \beta-1,2\) glycosidic linkage
• (b) \(\alpha-1,4\) glycosidic linkage
• (c) \(\beta-1,4\) glycosidic linkage
• (d) \(\alpha-1,4\) glycosidic linkage

(iii) The product of the following reaction is:
\[ C_2H_5 - \overset{O}{\overset{||}{C}} - CH_3 \quad \xrightarrow{H_2/Ni, \ \Delta} \quad ? \]

• (a) \( CH_3 - CH_2 - CH_2 - CH_2 - OH \)
• (b) \( CH_3 - CH(OH) - CH_2 - CH_3 \)
• (c) \( CH_3 - CH_2 - CH_2 - CH_3 \)
• (d) \( CH_3 - CH_2 - CH_2 - COOH \)

(iv) The pH of a 0.001 M HCl solution is \hspace{1cm}.

• (a) \(10\)
• (b) \(3\)
• (c) \(2\)
• (d) \(11\)

(v) The correct structure of the complex having IUPAC name sodium hexanitrocobaltate(III) is:

• (a) \( Na_3 [Co(NO_2)_5] \)
• (b) \( Na_4 [Co(NO_2)_6] \)
• (c) \( Na_3 [Co(NO_2)_6] \)
• (d) \( Na_4 [Co(NO_2)_5] \)

(vi) The number of particles present in a Face-Centered Cubic (FCC) unit cell is/are \hspace{1cm}.

• (a) \( 1 \)
• (b) \( 2 \)
• (c) \( 3 \)
• (d) \( 4 \)

(vii) The monomer used in the preparation of Teflon is 1cm.

• (a) E-caprolactam
• (b) vinyl chloride
• (c) styrene
• (d) tetrafluoroethene

(viii) Among the following, the vinylic halide is \hspace{1cm}.

• (a) \( R - CH(X) - R \)
• (b) \( CH_2 = CH - X \)
• (c) \chemfig{*6(=-=(-X)-=-)}
• (d) \( CH_2 = CH - CH_2 - X \)

(ix) The product of hydrolysis of propyne in the presence of 1% \(HgSO_4\) and 40% \(H_2SO_4\) is \underline{\hspace{1cm.

• (a) \( methanal \)
• (b) \( ethanal \)
• (c) \( propanal \)
• (d) \( propanone \)

(x) If the unit of rate constant is mol \(dm^{-3}s^{-1}\), the order of the reaction would be \underline{\hspace{1cm.

• (a) \( zero \)
• (b) \( 1 \)
• (c) \( 2 \)
• (d) \( 3 \)

Write the name of the metal nanoparticle used to remove E. coli bacteria from water.

Write the name of the reduction product formed when ethyl cyanide is treated with sodium and alcohol.

Complete the reaction:
\[ CH_3CH_2Cl \quad \xrightarrow{AgCN, \ alc., \ \Delta} \quad ? \]

Calculate the effective atomic number (EAN) of \([Co(NH_3)_6]^{3+}\) ion.

The compounds of Ti\(^{4+}\) ions are colourless due to \underline{\hspace{2cm.

Write the SI unit of molar conductivity.

Write the sign convention of work done during the expansion of gas.

Write the condition of reverse osmosis.

Derive an expression for maximum work obtainable during isothermal reversible expansion of an ideal gas from initial volume \(V_1\) to final volume \(V_2\).

What are interhalogen compounds? Write the chemical reaction when chlorine reacts with dry slaked lime.

What is a nanomaterial? Write the reaction involved in the sol-gel process during hydrolysis.

Write the classification of proteins with an example.

Calculate the time required to deposit 2.4 g of Cu, when 2.03 A of current is passed through \(CuSO_4\) solution.
(At. mass of Cu = 63.5 g mol\(^{-1}\))

Why are amines basic in nature? Among dimethylamine (pK\(_b\) = 3.27) and diethylamine (pK\(_b\) = 3.0), which one is more basic?

Explain the buffer action of the sodium acetate-acetic acid buffer.

Write the preparation of (a) diethyl ether and (b) ethyl cyanide from ethyl bromide.

Henry’s constant for CH\(_3\)Br(g) is 0.159 mol dm\(^{-3}\) bar\(^{-1}\) at 25\(^\circ\)C. Calculate its solubility in water at 25\(^\circ\)C if its partial pressure is 0.164 bar.

Nylon-6

Natural \textbf{rubber}

Define Lanthanide contraction. Write the balanced chemical equation when acidified \(K_2Cr_2O_7\) reacts with \(H_2S\).

Derive the relationship between molar mass, density of the substance, and unit cell edge length.

What is osmotic pressure? How will you determine the molar mass of a solute from osmotic pressure?

Rosenmund Reduction

Gattermann-Koch Formylation

Cannizzaro Reaction of Methanal

Calculate the standard enthalpy of combustion of methane, if the standard enthalpy of formation of methane, carbon dioxide, and water are -74.8, -393.5, and -285.8 kJ mol\(^{-1}\) respectively.

Silver Nitrite

Magnesium in Dry Ether

Alcoholic Sodium Hydroxide

For the reaction \( A + B \rightarrow P \):

If \([B]\) is doubled at constant \([A]\), the rate of reaction doubles.
If \([A]\) is tripled and \([B]\) is doubled, the rate of reaction increases by a factor of 6.
Calculate the rate law equation.

\(HOCl, HClO_2, HClO_3, HClO_4\) (acidic strength)

\(MF, MCl, MBr, MI\) (ionic character)

\(HF, HCl, HBr, HI\) (thermal stability)

Explain Wolff-Kishner reduction reaction. Write the preparation of propanone by using ethanoyl chloride and dimethyl cadmium.

Write postulates of Werner’s theory of coordination complexes. Write the name of a hexadentate ligand.

Define the electrochemical series and write its two applications.

Identify ‘A’, ‘B’ and ‘C’ in the following chain reaction and rewrite the chemical reactions:
\[ CH_3CH_2OH \xrightarrow{red 'P', Br_2} A \xrightarrow{KCN, alc} B \xrightarrow{LiAlH_4, Ether} C \]

Define acids and bases according to Bronsted-Lowry theory. Derive the relationship between pH and pOH.

Write the preparation of potassium dichromate from chromite ore.

Acetaldehyde to Isopropyl Alcohol

Cumene to Phenol

Anisole to Phenol

Extensive and Intensive Properties

Isobaric and Adiabatic Processes

Predict the type of cubic lattice of a solid element having edge length of 400 pm and density of 6.25 g/ml.
(Atomic mass of element = 60)

Derive the relation between half-life period and rate constant for a first-order reaction.

Write the net cell reaction during discharging of a lead accumulator.

Draw the structure of Peroxymonosulfuric Acid.

[Ni(Cl)\(_4\)]\(^{2-}\)

[Ni(CN)\(_4\)]\(^{2-}\)

Ethanentrile into Ethanal

Cyclohexane into Adipic Acid