Advertisements
Advertisements
Increase in enthalpy of the surroundings is equal to decrease in enthalpy of the system. Will the temperature of system and surroundings be the same when they are in thermal equilibrium?
Concept: undefined >> undefined
Predict the change in internal energy for an isolated system at constant volume.
Concept: undefined >> undefined
Advertisements
Although heat is a path function but heat absorbed by the system under certain specific conditions is independent of path. What are those conditions? Explain.
Concept: undefined >> undefined
Match Column (I) with Column (II).
| Column I | Column II |
| (i) Equilibrium | (a) ∆G > 0, K < 1 |
| (ii) Spontaneous reaction | (b) ∆G = 0 |
| (iii) Non spontaneous reaction | (c) ∆GΘ = 0 |
| (d) ∆G < 0, K > 1 |
Concept: undefined >> undefined
EΘ values of some redox couples are given below. On the basis of these values.
EΘ values: \[\ce{Br2 /Br- = + 1.90; Ag+ / Ag(s) = + 0.80}\];
\[\ce{Cu^{2+} / Cu(s) = + 0.34; I2(s) / I- = 0.54}\]
Concept: undefined >> undefined
The alkali metals are low melting. Which of the following alkali metal is expected to melt if the room temperature rises to 30°C?
Concept: undefined >> undefined
Alkali metals react with water vigorously to form hydroxides and dihydrogen. Which of the following alkali metals reacts with water least vigorously?
Concept: undefined >> undefined
The order of decreasing ionisation enthalpy in alkali metals is ______.
Concept: undefined >> undefined
Metals form basic hydroxides. Which of the following metal hydroxide is the least basic?
Concept: undefined >> undefined
The solubility of metal halides depends on their nature, lattice enthalpy and hydration enthalpy of the individual ions. Amongst fluorides of alkali metals, the lowest solubility of LiF in water is due to ______.
Concept: undefined >> undefined
In the synthesis of sodium carbonate, the recovery of ammonia is done by treating NH4Cl with Ca(OH)2. The by-product obtained in this process is ______.
Concept: undefined >> undefined
By adding gypsum to cement
Concept: undefined >> undefined
Which of the following elements does not form hydride by direct heating with dihydrogen?
Concept: undefined >> undefined
Metallic elements are described by their standard electrode potential, fusion enthalpy, atomic size, etc. The alkali metals are characterised by which of the following properties?
(i) High boiling point.
(ii) High negative standard electrode potential.
(iii) High density.
(iv) Large atomic size.
Concept: undefined >> undefined
Which of the following compounds are readily soluble in water?
(i) BeSO4
(ii) MgSO4
(iii) BaSO4
(iv) SrSO4
Concept: undefined >> undefined
Choose the correct statements from the following.
(i) Beryllium is not readily attacked by acids because of the presence of an oxide film on the surface of the metal.
(ii) Beryllium sulphate is readily soluble in water as the greater hydration enthalpy of Be2+ overcomes the lattice enthalpy factor.
(iii) Beryllium exhibits coordination number more than four.
(iv) Beryllium oxide is purely acidic in nature.
Concept: undefined >> undefined
When heated in air, the alkali metals form various oxides. Mention the oxides formed by Li, Na and K.
Concept: undefined >> undefined
Write Lewis strucure of \[\ce{O^{-}2}\] ion and find out oxidation state of each oxygen atom? What is the average oxidation state of oxygen in this ion?
Concept: undefined >> undefined
When a metal of group 1 was dissolved in liquid ammonia, the following observations were obtained:
(i) Blue solution was obtained initially.
(ii) On concentrating the solution, blue colour changed to bronze colour.
How do you account for the blue colour of the solution? Give the name of the product formed on keeping the solution for some time.
Concept: undefined >> undefined
The stability of peroxide and superoxide of alkali metals increase as we go down the group. Explain giving reason.
Concept: undefined >> undefined
