CLASS 10_ Summary of Reactions (Inorganic)

CHEMICAL REACTIONS AND EQUATIONS

      ACIDS, BASES AND SALTS

ACIDS

Properties:

1.      Active Metal + dil. Acid → Salt + Hydrogen

(Fe, Zn, Al, Mg reacts – Cu does not react as it lies below hydrogen) (HCl, H₂SO₄, - dilute HNO₃ does not produce hydrogen but very dilute HNO₃ liberates hydrogen with Mg and Mn)

This reaction is called simple displacement and used to prepare salts.

2.      Acid + Base → Salt + Water

(Base is metal oxide, metal hydroxide or ammonium hydroxide)

This is called Neutralisation reaction. It is used to prepare soluble salts.

3.      Metal Carbonate or Bicarbonate + dil. Acid → Salt + Water + CO₂  (HCl, H₂SO₄, HNO₃)

4.      Metal Sulphite + dil. Acid → Salt + Water + SO₂       (HCl, H₂SO₄, HNO₃)

5.      Metal Sulphide + dil. Acid → Salt + H₂S       (HCl, H₂SO₄, HNO₃)

BASES

Properties:

1.      Salt Solution I + Alkali → Insoluble Metal Hydroxide + Salt Solution II

(Alkali – NaOH, NH₄OH)     

2.      Ammonium Salt + Alkali   Salt + Water + Ammonia (NH₃ )

(Alkali- NaOH, CaO, Ca(OH)₂)

3.      Amphoteric Metal + Alkali → Salt + Hydrogen        (Al, Zn, Pb)

4.      Amphoteric Metal Oxide or Metal Hydroxide + Alkali → Salt + Water    (Al, Zn, Pb)

SALTS

Preparation

1.      Double Decomposition or Precipitation (Preparation of insoluble salt)

                           AB +CD → AD + CB

                                          i. Pb(NO₃)₂ + 2NaCl → PbCl₂  +2NaNO₃

                                       ii.  CaCl₂ + Na₂CO₃ → CaCO₃ + 2NaCl

                                    iii.  ZnSO₄ + (NH₄)₂CO₃ →ZnCO₃  + (NH₄)₂SO₄

                                         iv.            Pb(NO₃)₂ + Na₂SO₄ →PbSO₄ + 2NaNO₃

2.      Direct Combination or Synthesis (prepare both insoluble and soluble salt)

               Metal + Non-metal → Salt

                                                                              _i.            2Fe + 3Cl₂ → 2FeCl₃

                                                                         ii.            2Al + 3Cl₂ → 2AlCl₃

                                                                      iii.            Fe + S →  FeS

                                                                       iv.            Zn + S →  ZnS

      STUDY OF COMPOUNDS

Preparation of HCl and HNO₃

1.      Normal Salt + conc. H₂SO₄     Acid Salt + Volatile Acid

NaCl + conc. H₂SO_{4   *}→      NaHSO₄ + HCl

NaNO₃ + conc. H₂SO₄ →  NaHSO₄ + HNO₃

Note: Here conc. H2SO4 acts as a non-volatile acid.

                                                 * On the arrow < 200 C

Properties of HNO₃       

1.      Metal + dil. HNO₃  → Salt + Water + Nitric Oxide (NO)

2.      Metal + conc. HNO₃  → Salt + Water + Nitrogen dioxide (NO₂)

(Cu)

3.      Non-metal + conc. HNO₃  → Oxidised Product + Water + Nitrogen dioxide (NO₂)

(S, C)

Properties of Sulphuric acid

A.    Conc. H₂SO₄  as oxidising agent

1.      Metal + conc. H₂SO₄  → Salt + Water + Sulphur dioxide (Cu)

2.      Non-metal + conc. H₂SO₄  → Oxidised Product + Water + Sulphur dioxide (C,S)

B.     Conc. H₂SO₄  as Dehydrating agent

Substance    _* → Anhydrous product + Water (Sugar, Copper sulphate crystals)

* On the arrow conc.  H₂SO₄ 

Properties of HCl

1.      Metal nitrate + dil. HCl → Insoluble Metal chloride or Salt  + Nitric acid

(Lead nitrate, Silver Nitrate)

                   Pb(NO₃)₂ + 2HCl → PbCl₂  +2HNO₃

AgNO3 + HCl → AgCl  +  HNO₃

Preparation of NH₃

1.      Metal Nitride + Water → Metal Hydroxide + Ammonia (AlN. Mg₃N₂)

2.      Haber’s Process

N₂  + 3H₂  → 2NH₃

 

Properties of Ammonia

A.    Ammonia + Acid → Salt

( HCl, HNO₃ , H₂SO₄)

B.     NH₃ acts as a reducing agent

1.      Ammonia + Metal oxide → Metal + Water + Nitrogen (CuO)

2.      Ammonia + Chlorine 

      8NH₃ (excess) + 3Cl₂ → 6NH₄Cl + N₂

      NH₃ + 3Cl₂ (excess) → NCl₃ + 3HCl

C.     Catalytic Oxidation of Ammonia:

            4NH₃ + 5O₂  →   4NO + 6H₂O

        

D.    Burning of Ammonia in air:

            4NH₃ + 3O₂ → 2N₂+ 6H₂O

   

      Ostwald Process

4NH₃ + 5O₂    4NO + 6H₂O

2NO + O₂ → 2NO₂

H₂O + NO₂ + O₂ → 4 HNO₃

      Contact Process

4FeS₂ + 11O₂ → 2Fe₂O₃ + 8SO₂

2SO₂ + O₂ → 2SO₃

  SO₃ + H₂SO₄→ H₂S₂O₇

H₂S₂O₇ + H₂O → 2H₂SO₄