Why is glass considered as supercooled liquid?

What is the coordination number in a rock salt type structure?

What is meant by 'doping' in a semiconductor?

Red blood cells (RBC) are isotonic with .............. % NaCI solution.

KCl, KNO₃ etc. are preferred in a salt bridge because they have equal --------------

Define rate of reaction

Why do we add alum to purify water?

How is copper extracted from a low grade ore of it?

State the principle of the method of zone refining of metals.

Calculate the molality of H₂SO₄ if the density of 10% (w/w) aqueous solution of H₂SO₄ is 1.84 g cm^-3 (Molar mass of H₂SO₄ = 98g mol^-1).

What is the boiling point of an azeotrope of non - ideal solution showing positive deviations as compared to the boiling points of its components ?

What are isotonic solutions ? Give one example.

Between 2 M glucose solution and 1 M glucose solution, which one has a lower freezing point ?

Arrange the following solutions in increasing order of their van't Hoff factor :
0.1 M CaCI₂ , 0.1 M KCI , 0.1 M AI₂(SO₄) , 0.1 M C₁₂H₂₂O₁₁

How are the following properties of crystals affected by Schottky and Frenkel defects?
(i) Density
(ii) Electrical conductivity.

A NaCl crystal is found to have CsCl structure. Guess how it might have happened?

Explain superconductivity.

Differentiate between thermoplastic and thermosetting polymers.Give one example of each

How many Faradays/coulombs are required to produce
(i) 20.0 g of calcium from moltenCaCl₂?
(ii) 40.0 g of aluminium from molten AI₂O₃?

For the reaction at 500K,NO₂(g)+CO(g)\(\longrightarrow\)CO₂(g)+NO(g),the proposed mechanism is as below:
(i) NO₂+NO₂\(\longrightarrow\)NO+NO₃(slow)
(ii) NO₃+CO\(\longrightarrow\)CO₂+NO₂(fast) What is the rate law for the reaction?

For a reaction
\({ N }_{ 2 }+{ 3H }_{ 2 }\longrightarrow { 2NH }_{ 3 }\)
the rate of reaction measured as \(\frac { \Delta \left[ { NH }_{ 3 } \right] }{ \Delta t } \) was found to be \(2.4\times { 10 }^{ -4 } \ mol{ L }^{ -1 }{ S }^{ -1 }\) . calculate the rate of the reaction expressed in terms of
(i) \({ N }_{ 2 }\)
(ii) \({ H }_{ 2 }\)

A compound 'X' having molecular formula C₃H₇NO, reacts with Br₂ in presence of KOH to give another compound 'Y'. The compound Y reacts with NHO₂ to form ethanol and N₂ gas. Identify the compounds X and Y and write the reactions involved.

An organic compound 'A' having molecular formula C₂H₅O₂N reacts with HNO₂ and gives'B' C₂H₄O₃N₂. On reduction, 'A' gives a compound 'C' on treatment with HNO₂  gives 'D' which gives positive iodoform test. Identify 'A' .

Two isomeric compounds A and B having molecular formula C₄H₁₁N, both lose N₂ on treatment with HNO₂ and gives compound C and D respectively. C is resistant to oxidation but immediately responds to Lucas reagent, where as 'D' responds to Lucas reagent after 5 minutes and gives a positive iodoform test. Identify A and B.

(a) Explain the following:
(i) Henry's law about dissolution of a gas in a liquid.
(ii) Boiling point elevation constant for a solvent.
(b) A solution of glycerol (C₃H₈O₃) in water was prepared by dissolving some glycerol in 500 g of water. This solution as a boiling point of 100.42 ^oC. What mass of glycerol was dissolved to make this solution?
(K _b for water = 0.512 K kg mol^-1)

(a) Define Azeotropes and explain broefly minimum boiling azeotrope by taking suitable example.
(b) The vapour pressures of pure liquids A and B are 450 mm 700 mm of Hg respectively at 350 K. Calculate the composition of the liquid mixture if total vapour pressure is 600 mm of Hg. Also find the composition of the mixture in the vapour phase.

(a) Draw the structures of the following:
(i) XeF₄     (ii) H₂S₂O₇
(b) Explain the following observations:
(i) Phosphorus has a greater tendency for catenation than nitrogen.
(ii) The negative value of electron gain enthalpy is less for fluorine than that for chlorine.
(iii) Hydrogen fluoride has a much higher boiling point than hydrogen chloride.