Answer:
Characteristic
Alkali
metals
Alkaline
earth metals
1.
Tendency
to form
ionic/covalent
compounds.
Except
lithium, the compounds of alkali metals are ionic. Li compounds are somewhat
covalent due to small size of ion (high polarising power).
These
are less electropositive than al- kali metals. Except Be and Mg, other elements
form ionic compounds. Be and Mg compounds are somewhat covalent in nature.
2.
Nature
of oxides and their solubility in water.
Oxides
are basic, combine with water and form strong alkalies. Basic nature in-
creases gradually as the atomic number in- creases.
Except
\[BeO\]other MO oxides are basic. They combine with water and form basic
hydroxides. The basic nature in-creases from top to bottom, less basic than
the oxides of alkali metals, \[BeO\]and \[MgO\] are insoluble in water.
3.
Formation
of oxo- salts.
React
readily with oxy acids and form oxo salts. Salts are colourless, crystalline
and ionic in nature.
React
with oxy acids and form salts. Salts are colourless, crystalline and ionic in
nature except Be salts.
4.
Solubility
of oxosalts:
Carbonates.
Bicarbonates.
Nitrates.
Sulphates.
Carbonates
are highly soluble in water.
Known
in free state.
Soluble
in water.
Soluble
in water.
Soluble
in water.
Carbonates
are insoluble in water.
Only
known in solution.
Do
not exist in solid state. Soluble in water.
Solubility
decreases \[BeS{{O}_{4}}\], \[MgS{{O}_{4}}\] are soluble, \[CaS{{O}_{4}}\] is
sparingly soluble while \[SrS{{O}_{4}}\] and \[BaS{{O}_{4}}\]are insoluble.
5.
Thermal
stability of oxosalts:
Carbonates.
Nitrates.
Sulphates.
Stability
increases.
only
\[L{{i}_{2}}C{{O}_{3}}\]decomposes.
Except
\[L{{i}_{2}}C{{O}_{3}}\] decompose into nitrite and oxygen.
Stable
towards heat.
Less
stable decompose into oxide and \[C{{O}_{2}}\]stability increases.
Decompose
into \[N{{O}_{2}}\] and \[{{O}_{2}}\] besides oxide.
Decompose
on heating to oxide, \[S{{O}_{2}}\] and\[{{O}_{2}}\].
You need to login to perform this action.
You will be redirected in
3 sec