THERMAL Stability of alkaline metal carbonates and Alkaline earth metal carbonates

Group 2 -BeCO3<MgCO3<CaCO3 <SrCO3<BaCO3

Group 1 -Li2CO3<Na2CO3<KCO3<Rb2CO3<Cs2CO3

Li2CO3 Decomposes easily on heating to give CO2

Li2CO3 → Li2O + CO2

All other Group 1 elements can be easily decomposed.

GROUP 2 elements can be decomposed : Only more heat is required as we move down

Hope This Helps

Hello Student

CrO5 , also known as Chromium peroxide is synthesized in the following way from Potassium Dichromate:

KCr2O7 + H2SO4 + 4H2O2 -------Ice Cold Ether-----> K2SO4 + 2CrO5 + 5H2O

Note : Ether Stabilises CrO5 .

It is blue in colour and has butterfly structure .

Chromium is in +6 Oxidation state in CrO5.

Hello Student ,

Heat and pH have the following effects on Potassium Dichromate

Effect of Heat on K2Cr2O7 (Oxidation State of Cr remains constant)

4K2Cr2O7 ----Heat----> 4K2CrO4 + 2Cr2O3 + 3O2

Effect of pH on K2Cr2O7 (Oxidation State of Cr Remains Constant)

1. Cr2O7^ 2- + H2O ---pH = 8----> CrO4^ 2- + 2H+
2. CrO4^ 2- + 2H+ ---pH = 4----> Cr2O7^ 2- + H2O

Please note the Oxidation number of Cr is constant in both the cases .

Hello Student,

• Oxidane is the IUPAC name of the compound we are most familiar with i.e Water or H2O
• Azane is the IUPAC name of Ammonia or NH3
• Phosphane , is the IUPAC name of PH3 Which also belongs to group 15 like NH3.

The IUPAC name are not used commonly.

Hello Student ,

H2O2 or oxygenated water can be prepared in the following ways : -

1. Merk's Method - Na2O2 + H2SO4(Ice Cold, 20%) = Na2SO4 + H2O2
2. Laboratory Method - 3[BaO2.8H2O] + 2H3PO4 = Ba3(PO4)2 +  3H2O2 + 24H2O
3. Electrolysis of Cold 50% H2SO4
4. Other - BaO2.8H2O + H2O + CO2 = BaCO3 + H2O2 + 8H2O

Hello Student,

From Water H2 preparation can mainly be done in two ways , which are as follows :-

By Action of Metals, Na, K , Mg , Zn ,Fe etc .

1. 2Na + 2H2O = 2NaOH + H2
2. Mg + H2O(Boiling Water) = MgO + H2

By Action of hydrides , NaH , CaH2 etc

1. CaH2 + 2H2O = Ca(OH)2 + 2H2

Hope this helps .

• Cengage inorganic chemistry.
  
• Concise inorganic chemistry by JD lee.
  

Hello Student,

The transition elements in ground state or stable oxidation state have (n-1)d^1-9 ns^1-2 electronic configuration.

Note Zn, Cd, Hg and Cn are not considered transition elements because in their ground state and stable oxidation state they do not have (n-1)d^1-9 configuration rather they have (n-1)d^10 configuration.

• Equilibrium

• Chemical Bonding and Molecular structure

• Electrochemistry

• Chemical Kinetics

• Coordination Compounds

• S, P, D and F Block Elements

• Atomic structure