is preferred over NaCl for clearing ice on roads particularly in very cold countries. This is because:
1. is less soluble in than NaCl.
2. is hygroscopic but NaCl is not.
3. Eutectic mixture of freezes at while that of freezes at .
4. NaCl makes the road slippery but does not.
The incorrect statement among the following is-
1. The milk of magnesia used as an antacid is chemically
2. Stability of alkali metal peroxides increases with an increase in atomic number.
3. Hydration energy of AgF is higher than its lattice energy.
4. Anhydrous cannot be prepared by direct heating of .
The property of alkali metals that increases with increasing atomic number is -
1. First ionization energy.
2. Electronegativity.
3. Hydration energy of the univalent ion.
4. Atomic radius.
A metal [X] heating on nitrogen gas gives [Y]. [Y] on treatment with gives a colourless gas which when passed through solution gives a blue colour. [Y] is-
1.
2.
3.
4.
A compound (A) is used in the preparation of washing soda to recover ammonia in Solvay's process. When CO2 is bubbled through an aqueous solution of (A), the solution turns milky. It is used in whitewashing due to its disinfectant nature. The chemical formula of A is :
1.
2. CaO
3.
4.
The effect of addion of gypsum to cement is-
1. It reduces the setting time of cement .
2. The setting time of cement increases.
3. The colour of cement becomes light .
4. A shining surface is obtained.
The strongest factor responsible for reducing action of Li metal in an aqueous solution is :
1. Sublimation enthalpy .
2. Ionisation enthalpy.
3. Hydration enthalpy .
4. Electron-gain enthalpy.
In the reaction (superoxide) the metal is -
1. Li
2. Na
3. K
4. Ba
Sodium reacts with water less vigorously than potassium because-
1. It has a higher atomic weight.
2. It is less electropositive .
3. It is more electronegative.
4. It is a metal .
The correct relation about the density of Na and K is
1. Na > K
2. Na = K
3. K > Na
4. Li > K