What is the mixture of CaC2 and N2 called? How is it prepared?
It is called Nitrolime.
It is prepared by heating CaC2 with N2 at high temperature.
CaC2 + N2 ——–> CaCN2 + C
Match the elements given in Column I with the colour they impart to the flame given in Column II.
| Column I | Column II |
| (i) Cs | (a) Apple green |
| (ii) Na | (b) Violet |
| (iii) K | (c) Brick red |
| (iv) Ca | (d) Yellow |
| (v) Sr | (e) Crimson red |
| (vi) Ba | (f) Blue |
Explain the significance of sodium, potassium, magnesium and calcium in biological fluids.
Why does the solution of alkali metals becomes blue in liquid ammonia? Give the chemical equation also.
Arrange the following in the increasing order of solubility in water.
MgCl2, CaCl2, SrCl2, BaCl2
Which of the carbonates given below is unstable in air and is kept in C02 atmosphere to avoid decomposition.
(a) BeCO3
(b) MgC03
(c) CaC03
(d) BaCO3
Discuss the trend of the following:
(i) Thermal stability of carbonates of Group 2 elements.
(ii) The solubility and the nature of oxides, of Group 2 elements.
(a) What makes lithium to show properties uncommon to the rest of the alkali metals?
(b) When is a cation highly polarising? Which alkali metal cation has the highest polarising power?
The order of decreasing ionization enthalpy in alkali metals is
(a) Na > Li > K > Rb (b) Rb < Na < K < Li
(c) Li > Na > K > Rb (d) K < Li < Na < Rb
Match the compounds given in Column I with their uses mentioned in Column II.
| Column I | Column II |
| (i) CaC03 | (a) Dentistry, ornamental work |
| (ii) Ca(OH)2 | (b) Manufacture of sodium carbonate from caustic soda |
| (iii) CaO | (c) Manufacture-of high quality paper |
| (iv) CaS04 | (d) Used in white washing |
The reducing power of a metal depends oh various factors. Suggest the factor which makes Li, the strongest reducing agent in aqueous solution.
(a) Sublimation enthalpy (b) Ionisation enthalpy
(c) Hydration enthalpy (d) Electron-gain enthalpy
Several sodium compounds find use in industries. Which of the following compounds are used for textile industry?
(a) Na2C03
(b) NaHC03
(c) NaOH
(d) NaCl
Lithium resembles magnesium in some of its properties. Mention two such properties and give reasons for this resemblance.
Why is LiF almost insoluble in water whereas LiCl soluble not only in water but also in acetone?
When heated in air, the alkali metals form various oxides. Mention the oxides formed by Li, Na and K.
Match the elements given in Column I with the properties mentioned in Column II.
| Column I | Column II |
| (i) Li | (a) Insoluble sulphate |
| (ii) Na | (b) Strongest monoacidic base |
| (iii) Ca | (c) Most negative E ° value among alkali metals |
| (iv) Ba | (d) Insoluble oxalate ‘ |
| (e) 6s2 outer electronic configuration |
Explain why can alkali and alkaline earth metals not be obtained by chemical reduction method.
Beryllium and magnesium do not give colour to flame whereas other alkaline earth metals do so. Why?
The hydroxides and carbonates of sodium and potassium are easily soluble in water while the corresponding salts of magnesium and calcium are sparingly soluble in water. Explain.
Name the alkaline earth metals whose salt do not impart colour to a non-luminous flame.
Starting with sodium chloride how would you proceed to prepare.
(i) Sodium metal (ii) Sodium hydroxide
(iii) Sodium peroxide (iv) Sodium carbonate?
Describe two important uses of each of the following: ,
(i) caustic soda (ii) sodium carbonate (iii) quick lime
What is the effect of heat on the following compounds (Give equations for the reactions)? (i) CaC03 (ii) CaSO4 2H2O
(a) Compare four properties of alkali metals and alkaline earth metals.
(b) What happens when alkali metals are dissolved in ammonia?
(c) MgCl2 is electrolysed.
Which out of the following can be used to store an alkali metal?
H2O, C2H5OH and Benzene
The alkali metals are low melting. Which of the following alkali metals is expected to melt if the room temperature rises to 30 °C?
(a) Na (b) K (c) Rb (d) Cs
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
(a) ionic nature of lithium fluoride. . .
(b) high lattice enthalpy. ‘
(c) high hydration enthalpy for lithium ion.
(d) low ionization enthalpy of lithium atom.
Compare the alkali metals and alkaline earth metals with respect to (i) ionization enthalpy, (ii) basicity of oxides, (iii) solubility of hydroxides.
When alkali metal dissolves in liquid ammonia, the solution can acquire different colours. Explain the reason for this type of colour change.
What happens when
(i) Sodium metal is dropped in water?
(ii) Sodium metal is heated in free supply of air?
(iii) Sodium peroxide dissolves in water?
Explain the following:
(a) Lithium iodide is more covalent than lithium fluoride.
(b) Lattice enthalpy of LiF is maximum among all the alkali metal halides.