Assertion (A): | When an alkali metal dissolves in liquid NH3 the solution acquires different colors. |
Reason (R): | Paired electrons are present in ammonia. |
1. | (A) is true and (R) is the correct explanation of (A). |
2. | (A) is true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false |
Arrange the following ions in increasing order of their mobility in the aqueous solution:
Li+, Na+, K+, Rb+ and Cs+
The chemical formula of Plaster of Paris is:
1.
2.
3.
4. 3CaSO4.H2O
Alkali metal with the lowest melting point is -
1. Na
2. K
3. Rb
4. Cs
The alkali metal that gives hydrated salts is -
1. Li
2. Na
3. K
4. Cs
The most stable (thermally) carbonate of alkaline earth metal is-
1. MgCO3
2. CaCO3
3. SrCO3
4. BaCO3
The incorrect statement about alkali metals is -
1. They have low density.
2. They have high ionization enthalpy.
3. They are highly reactive.
4. They show photoelectric effect.
The characteristic of alkaline earth metals is that-
1. Their general oxidation state is +1
2. They have a smaller size than alkali metals.
3. They are electronegative in nature.
4. They are strong oxidizing agents.
Sodium is less reactive than potassium because-
1. Potassium loses electron easily.
2. Sodium loses electron easily.
3. Size of sodium is larger than potassium.
4. Nuclear charge is more on potassium.
The correct diagonal relation of Li and Mg among the following is -
1. Both form solid bicarbonates.
2. Their oxides are less soluble in water.
3.Their carbonates are ionic in nature.
4. Both form peroxides and superoxides.