Explain the stability of carbonates & bicarbonates of alkali metals .

Explain the stability of carbonates & bicarbonates of alkali metals . 
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Answer :

The alkali metals form salts with all the oxo-acids. They are generally soluble in water and thermally stable. Their carbonates (M2CO3) and in most cases the hydrogencarbonates (MHCO3) also are highly stable to heat. As the electropositive character increases down the group, the stability of the carbonates and hydorgencarbonates increases. Lithium carbonate is not so stable to heat; lithium being very small in size polarises a large CO3 2– ion leading to the formation of more stable Li2O and CO2. Its hydrogencarbonate does not exist as a solid.  

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Last Answer : Ans This is due to increased nuclear charge and smaller size.

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what are the common physical features of alkali metals?

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what do you understand by “Non stoichiometric hydrides”? Do you think this type of hydrides to be formed by alkali metals? Justify your answer.

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How does the atomic and Ionic Radii of alkaline earth metals vary in comparison to alkali metals

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Last Answer : The atomic and ionic radii of the alkaline earth metals are smaller than those of the corresponding alkali metals in the same periods. This is due to the increased nuclear charge in these elements. Within the group, the atomic and ionic radii increase with increase in atomic number.

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Last Answer : The atomic and ionic radii of alkali metals increase on moving down the group i.e., they increase in size while going from Li to Cs.

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How the ionization enthalpy varies in alkali metals

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Why I group elements are called alkali metals ?

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Give the names of four alkali metals:

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Last Answer : ANSWER: LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CESIUM, AND FRANCIUM  

Name any four alkali metals.

Description : Name any four alkali metals.

Last Answer : ANSWER: LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CESIUM, AND FRANCIUM

The elements in group 1A of the periodic table are called: w) halogens x) alkaline earths y) alkali metals z) rare earths

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Which of the following alkali metals has highest specific heat? (1) Caesium (2) Rubidium (3) Potassium (4) Lithium

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Lime and soda ash are added to water to remove (A) Bicarbonates & sulphates of calcium and magnesium (B) Undesirable taste and odour (C) Bacteria (D) Its corrosiveness

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Consider the following statements: 1. Carbonate hardness is due to bicarbonates. 2. Non-carbonate hardness is due to sulphates and chlorides of Ca and Mg. 3. Both the hardnesses can be removed by lime-soda method. 4. Both the hardnesses can be removed by ion-exchange method. Which of these statements are correct? (a) 1, 2 & 3 only (b) 1, 2 & 4 only (c) 2, 3 & 4 only (d) 1, 2, 3 & 4

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Select similarly between alkali metals and coinage metals.

Description : Select similarly between alkali metals and coinage metals.

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Description : Standard reduction potential of alkali metals have high negative values.

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Description : Hydrogen shows similarity with alkali metals as well as halogens.

Last Answer : Explain : Hydrogen shows similarity with alkali metals as well as halogens.

Give reasons : a. Alkali metals have low ionization energies.  b. Inert gases have exceptionally high ionization energies.

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What is the most active group of nonmetals noble gases alkaline earth halogens alkali metals?

Description : What is the most active group of nonmetals noble gases alkaline earth halogens alkali metals?

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Who has the most active group of nonmetals noble gases alkaline earth halogens alkali metals?

Description : Who has the most active group of nonmetals noble gases alkaline earth halogens alkali metals?

Last Answer : Kevin