List of top Chemistry Questions asked in Maharashtra Board Class XII Exam

HF, HCl, HBr, HI (thermal stability)

MF, MCl, MBr, MI (ionic character)
\(\text{HClO}, \text{HClO}_2, \text{HClO}_3, \text{HClO}_4\) (acidic strength)

Arrange the following in the increasing order of the property mentioned:

(i) HClO, HClO₂, HClO₃, HClO₄ (acidic strength)

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

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

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.
Alcoholic Sodium Hydroxide
Magnesium in Dry Ether
Silver Nitrite

What is the action of the following on ethyl bromide ?
(a) silver nitrite
(b) Mg in dry ether 
(c) alcoholic sodium hydroxide

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.

Write chemical reactions involved in Cannizzaro Reaction of Methanal

Write chemical reactions involved in Gattermann-Koch Formylation

Write chemical reactions involved in Rosenmund Reduction

What is osmotic pressure? How will you determine the molar mass of a solute from osmotic pressure?
Derive the relationship between molar mass, density of the substance, and unit cell edge length.
Define Lanthanide contraction. Write the balanced chemical equation when acidified \( K_2Cr_2O_7 \) reacts with \( H_2S \).

Write the structure and name of the monomer of Natural rubber

Write the structure and name of the monomer of Nylon-6.

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.
Write the preparation of (a) diethyl ether and (b) ethyl cyanide from ethyl bromide.
Explain the buffer action of the sodium acetate-acetic acid buffer.
Why are amines basic in nature? Among dimethylamine (pK$_b$ = 3.27) and diethylamine (pK$_b$ = 3.0), which one is more basic?

Calculate the time required to deposit 2.4 g of Cu, when 2.03 A of current is passed through \( \text{CuSO}_4 \) solution. 
(At. mass of Cu = 63.5 g mol\(^{-1}\))

Write the classification of proteins with an example.
What is a nanomaterial? Write the reaction involved in the sol-gel process during hydrolysis.