Question

Difference between decomposition and double decomposition reaction

Answer 1

hi frnd your answer is as follows
i think u have written wrong question
there is double displacement reaction in replace of double decomposition reaction

Answer 2

I. In simple decomposition one pure substance, which is a compound, breaks up into two or more substances.

The products of decomposition are elements, compounds or both.

Examples:

(1) 2HI = H2 + I2 (a compound decomposes to its 2 constituent elements )

(2) 2Pb(NO3)2 = 2PbO + 4NO2 + O2 (a compound decomposes to 1 element and 2 compounds)

(3) NH4Cl = NH3 + HCl (a compound breaks up into 2 other compounds)

A decomposition may or may not be a redox (oxidation-reduction) reaction. In the above three examples, the first two are redox reactions but the last one is non-redox.

II. In double decomposition two substances, both of which are compounds, interchange ions or parts to form two new substances.

The products are always compounds in such reactions.

Examples:

(1) AgNO3 + NaCl = AgNO3 + NaNO3

(2) Pb(NO3)2 + 2KI = PbI2 + 2KNO3

A double decomposition reactions is always non-redox in nature, as it does not result in change in oxidation number of any constituent element