Advertisements
Advertisements
प्रश्न
The alkali metals are low melting. Which of the following alkali metal is expected to melt if the room temperature rises to 30°C?
विकल्प
Na
K
Rb
Cs
Advertisements
उत्तर
Cs
Explanation:
Among alkali metals, melting point decreases as the strength of metallic bonding decreases with increasing size of the atom. Thus, Cs has the lowest melting point (28.5°C) and will melt at 30°C.
APPEARS IN
संबंधित प्रश्न
What are the common chemical features of alkali metals?
Explain why alkali and alkaline earth metals cannot be obtained by chemical reduction methods?
Write a balanced equation for the reaction between KO2 and water.
Which of the alkali metal is having least melting point?
Which one of the following alkali metals gives hydrated salts?
What are the common physical features of alkali metals?
Alkali metals react with water vigorously to form hydroxides and dihydrogen. Which of the following alkali metals reacts with water least vigorously?
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 ______.
By adding gypsum to cement
When heated in air, the alkali metals form various oxides. Mention the oxides formed by Li, Na and K.
The valence shell electronic configuration of alkali metals is ______.
Match List-I with List-II.
| List-I | List-II |
| (Metal) | (Emitted light wavelength (nm)) |
| (a) Li | (I) 780.0 |
| (b) Na | (II) 455.5 |
| (c) Rb | (III) 670.8 |
| (d) Cs | (IV) 589.2 |
Choose the most appropriate answer from the options given below:
A white precipitate was formed when BaCl2 was added to extract of an inorganic salt. Farther, a gas 'X' with characteristic odour was released when the formed white precipitate was dissolved in dilute HCl. The anion present in the inorganic salt is ______.
Nitrogen combines with metals to form ______.
Given below are two statements, one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Lithium salts are hydrated.
Reason (R) : Lithium has higher polarising power than other alkali metal group members.
In the light of the above statements, choose the most appropriate answer from the options given below :
