Question

tell me rexn of 2nd chapter class10

Answer 1

I can't understand the question

Answer 2

Combination Reaction :Two or more reactant combine to form a single product.
2 Mg (s) + O2 (g) ? 2 MgO Magnesium Oxygen Magnesium oxide (White ash)
(basic) turns Red litmus blue


2. Decomposition Reaction: A single compound decomposes or break down to give two or moresimpler substances.
2 FeSO4 (s). Fe2 O3 (s) + SO2 (g) + SO3(g) Ferrous Sulphate Ferric oxide Sulphur Sulphur (green) (brown) dioxide trioxide


3. Displacement Reaction: A more reactive element [metal] displaces less reactive elemen [metal] from its aqueous salt soln Fe (s) + ZnSO4 (aq)      ? FeSO4 (aq) + Zn (s) (Colourless) (green)


4. Double Displacement Reaction: Aqueous soln of two ionic compounds react by exchange of their ions is called double displacement Reaction BaCl2 (aq) + Na2SO4 (aq) ? BaSO4 (s) + 2 NaCl (aq) Pb(NO3)2 + 2 KI (aq) ? PbI2 ( ? ) + 2 KNO3 (aq)


5. Oxidation Reaction: In oxidation reaction, addition of oxygen or removal of hydrogen or loss of electron takes place. 2 Mg(s) + O2(g)  ?  2MgO (s)  2 Cu + O2  ?  2 CuO (Black ) (Copper II Oxide) 


6. Reduction Reaction: In reduction Reaction addition of hydrogen or removal of oxygen or gain of electron takes place. CuO(s) + H2(g)  ?Cu(s) + H2 O (l) 


7. Redox Reaction: Reaction involving both oxidation and reduction simultaneously CuO (s)+ H2   ?  Cu(s) + H2 O (l). 


8. Exothermic Reaction: Reaction in which heat is evolved. C (s) + O2 (g)   ? CO2 (g) + Heat


10. Neutralisation Reaction : When an acid and a base react together to form salt and water.  HCl (aq)  +  NaOH (aq)  ?  H2O (l)  +  NaCl (aq)  (acid) (base)  (Water) (Salt)  Hydrochloric acid  Sodium hydroxide   Sodium Chloride