Hydration Enthalpy and Lattice Enthalpy (Group 2)

Q.

Among the sulphates of alkaline earth metals, the solubility of ${\mathrm{BeSO}}_4$and ${\mathrm{MgSO}}_4$ in water, respectively, are

1. Poor and high

2. High and high

3. Poor and poor

4. High and poor

Q. Property of alkaline earth metals that increases with their atomic number

1. Solubility of their hydroxides in water

2. Ionisation energy

3. Solubility of their sulphates in water

4. Electronegativity

Q.

Alkaline earth metal compounds are less soluble in water than corresponding alkali metal compounds because the former have

1. Low lattice energies

2. Higher covalent character

3. Higher ionization energies

4. Higher ionic character

Q. 13. What will be the packing fraction of NaCl crystal ? How to calculate it ?

Q.

Halides of alkaline earth metals form hydrates such as MgCl₂.6H₂O, CaCl₂.6H₂O, BaCl₂.2H₂O and SrCl₂.2H₂O. This shows that halides of group 2 elements

1. Can act as dehydrating agents

2. Can absorbs moisture from air

3. All of the above

4. Are hygroscopic in nature

Q. 3. Density of equilibrium mixture of N2O4 and NO2 at 1 atm and 384K is 1.84 g/dm3 . Equilibrium constant of the following reaction is? N2O4 ----> 2NO2

Q.

Amongst the following hydroxides, the One which has the highest value of Ksp at ordinary temperature is

1. Mg(OH)₂

2. Ca(OH)₂

3. Sr(OH)₂

4. Ba(OH)₂

Q. Why boiling point of water is more than hydrogen fluoride?

Q.

Solubility of s block halides in water depends upon:

1. 1) Ionization energy of metal

2. 2) Lattice energy of compound

3. 3) Hydration energy of ions

4. 4) Both 2 and 3

Q. On heating 1.763 g of hydrated BaCi2 to drynes1.505 g of anhydrous salt remained. Hence theformula of the hydrate is (Atomic weight ofBa 137)3(2) BaCl2-H20(1) BaC12 2 H2O(3) BaCl2 2H2O(4) BaCl2 5H2O

Q. 17. The alkali metals from salt-like hydrides by the direct synthesis at elevated temperature. The thermal stability of these hydrides decreases in which of the following orders ? [AIPMT (Prelims)-2008] (1) LiH > NaH > KH > RbH > CsH (2) CsH > RbH > KH > NaH > LiH (3) KH > NaH > LiH > CsH > RbH (4) NaH > LiH > KH > RbH > CsH

Q. 6. Calculate the mole fraction of ethylene glycol in a solution containing 20percent of glycol by mass

Q. which is correct thermal stability orderfor H2E( E= o, s, se, Te, po)

Q.

The hydration energy of $M{g}^{2+}$ is greater than that of

1. All of the above

2. Na⁺

3. Al³⁺

4. Be²⁺

Q. How many moles of magnesium phosphate, will contain 0.25 mole of oxygen atoms?

Q. what is the minimum volume of water required to dissolve 1g of calcium sulphate at 298 k

Q.

Property of the alkaline earth metals that increases with their atomic number is

1. Ionisation energy

2. Solubility of their hydroxides

3. Solubility of their sulphates

4. Electronegativity

Q. 30. 40% N2O4 molecules are dissociated in a sample ofgas at 27C and 760mmHg Calculate the density of the equilibrium mixture?

Q.

Property of the alkaline earth metals that increases with their atomic number is:

1. Ionization energy

2. Solubility of their hydroxides

3. Electro-negativity

4. Solubility of their sulphates

Q. The solubility order of the chlorides of the alkali metals is

1. NaCl > KCl > RbCl > CsCl
2. CsCl > RbCl > KCl > NaCl
3. KCl > NaCl > RbCl > CsCl
4. Cs Cl > RbCl > NaCl > KCl

Q. Name two elements in each case :
Alkali metals

Q. 35. 40% N_2O_4 molecules dissociates into NO_2 in a sample of gas at 27 degree celcius and 760 torr. The density of the equilibrium mixture is ??

Q. Which of the following alkali metal(s) form complex hydrides?

1. K
2. Li
3. Na
4. Rb

Q.

The hydration energy of $M{g}^{2+}$ is greater than that of

1. $N{a}^{+}$
2. $A{l}^{3+}$
3. $B{e}^{2+}$
4. All of the above

Q. Match the column:
$\begin{array}{cccc}& & & \\ & Column-I& & Column-II\\ \left(a\right)& Be& \left(p\right)& Showdiagonalrelstionshipwithotherelements\\ \left(b\right)& Mg& \left(q\right)& Highesthydrationenergyofcationamongtheelements\\ \left(c\right)& Ca& \left(r\right)& Cationhaslowesthydratedsizeinaqueoussolution\\ \left(d\right)& Sr& \left(s\right)& Metal\left(s\right)whichdissolveinliquidammoniatogivedeepbluesolution\\ & & \left(t\right)& s-blockelements\end{array}$

1. (a) p, q, t; (b) p, t; (c) s, t; (d) r, s, t
2. (a) p, q, t; (b) s, t; (c) p, t; (d) r, s, t
3. (a) r, s, t; (b) p, t; (c) s, t; (d) p, q, t
4. (a) p, q, t; (b) r, s, t; (c) s, t; (d) p, t

Q.

Equal volumes of 0.002 M solutions of sodium iodate and cupric chlorate are mixed together. Will it lead to precipitation of copper iodate? (For cupric iodate K_sp = 7.4 × 10^–8).

Q. The order of solubility of aluminium halides in water decreases in the order, Alf3> Alcl3> Albr3 >All3 why?

Q. Which of the following compounds is readily soluble in water?

1. $BeS{O}_4$
2. $MgS{O}_4$
3. $BaS{O}_4$
4. $SrS{O}_4$

Q.

Which one of the following alkali metals gives hydrated salts?

(a) Li (b) Na (c) K (d) Cs

Q. how does ionic character affects solubility ??