HSC Science (Electronics) 12th Standard Board Exam - Maharashtra State Board Question Bank Solutions

What is the action of hydrochloric acid on the following?

\[\ce{NH3}\]

What is the action of hydrochloric acid on the following? 

\[\ce{Na2CO3}\]

Define enthalpy of sublimation.

Calculate C-Cl bond enthalpy from following reaction:

CH₃Cl_(g) + Cl_2(g) → Ch₂Cl_2(g) + HCl_(g) ΔH° = -104KJ

If C-H, Cl-Cl and H-Cl bond enthalpies are 414, 243 and 431 KJ-Mol^-1 respectively.

Explain impurity defect in stainless steel with diagram

Identify the product ‘D’ in the following sequence of reactions:

\[\ce{H3C - CH2 - CH2 - Cl \underset{KOH}{\overset{Alc}{->}} 'B' \overset{HBr}{->} 'C' \underset{Elther}{\overset{Na}{->}}'D'}\]

On the basis of valence bond theory explain the nature of bonding in [CoF₆]³ ion.

For the reaction: Cl₂(g) → 2Cl(g), _______.

(A) ΔH is positive, ΔS is positive

(B) ΔH is positive, ΔS is negative

(C) ΔH is negative, ΔS is negative

(D) ΔH is negative, ΔS is positive

The amine which reacts with nitrous acid to give yellow oily compound is _______.

(A) ethylamine

(B) isopropylamine

(C) secondary butylamine

(D) dimethylamine

Identify ‘A’ and ‘B’ in the following reaction :

\[\ce{CH3 - CH = CH2 ->[HBr]'A' ->[alc.KOH]'B'}\]

What will be the action of the mixture of sodium nitrite and dilute hydrochloric acid on ethyl amine

State and explain Markownikoff's rule with suitable example

What type of point defect is produced when AgCl is doped with CdCl₂?

Determine the osmotic pressure of a solution prepared by dissolving 2.5 × 10⁻² g of K₂SO₄ in 2L of water at 25°C, assuming that it is completely dissociated.

(R = 0.0821 L atm K⁻¹ mol⁻¹, Molar mass of K₂SO₄ = 174 g mol⁻¹)

What is molecular formula of oleum?

(a) H₂SO₃

(b) H₂SO₄

(c) H₂S₂O₇

(d) H₂S₂O₈

Which of the following is not a colligative property?

[NiCl₄]²⁻ is paramagnetic, while [Ni(CO)₄] is diamagnetic, though both are tetrahedral. Why? (Atomic number of Ni = 28)

What happens when the external pressure applied becomes more than the osmotic pressure of solution?

Blood cells are isotonic with 0.9% sodium chloride solution. What happens if we place blood cells in a solution containing

(i) 1.2% sodium chloride solution?

(ii) 0.4% sodium chloride solution?

Define the following term:

Schottky defect