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प्रश्न
Why are alkali metals not found in nature?
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उत्तर
Alkali metals include lithium, sodium, potassium, rubidium, cesium, and francium. These metals have only one electron in their valence shell, which they lose easily, owing to their low ionization energies. Therefore, alkali metals are highly reactive and are not found in nature in their elemental state.
संबंधित प्रश्न
Why are lithium salts commonly hydrated and those of the other alkali metal ions usually anhydrous?
Write a balanced equation for the reaction between Na2O and CO2.
Which of the alkali metal is having least melting point?
The alkali metals are low melting. Which of the following alkali metal is expected to melt if the room temperature rises to 30°C?
The order of decreasing ionisation enthalpy in alkali metals is ______.
Metals form basic hydroxides. Which of the following metal hydroxide is the least basic?
Which of the following compounds are readily soluble in water?
(i) BeSO4
(ii) MgSO4
(iii) BaSO4
(iv) SrSO4
When a metal of group 1 was dissolved in liquid ammonia, the following observations were obtained:
(i) Blue solution was obtained initially.
(ii) On concentrating the solution, blue colour changed to bronze colour.
How do you account for the blue colour of the solution? Give the name of the product formed on keeping the solution for some time.
Ions of an element of group 1 participate in the transmission of nerve signals and transport of sugars and aminoacids into cells. This element imparts yellow colour to the flame in flame test and forms an oxide and a peroxide with oxygen. Identify the element and write chemical reaction to show the formation of its peroxide. Why does the element impart colour to the flame?
The ease of absorption of the hydrated alkali metals ions in an ion-exchange resin follows the order:
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:
The correct order of hydration enthapies of alkali metal ions is ______.
Nitrogen combines with metals to form ______.
The correct order of conductivity of ions in water is ______.
