Question

Identify the decomposition reaction. 2nh3 + h2so4 ⟶ (nh4)2so4 2nabr + ca(oh)2 ⟶ cabr2 + 2naoh 2 no2 ⟶ 2 o2 + n2 3pb + 2h3po4 ⟶ 3h2 + pb3(po4)2

Answer 1

A decomposition reaction should look like

A ------> B +C+...

It has to have only one reactant and several products.

2 NO2 ⟶ 2 O2 + N2

Answer 2

Answer : The correct option is, $2NO_2\rightarrow 2O_2+N_2$

Explanation :

Decomposition reaction : It is a type of reaction in which a single larger compound decomposes to give two or more smaller molecules as a product.

The general representation of decomposition reaction is :

$AB\rightarrow A+B$

From the given options,

$2NO_2\rightarrow 2O_2+N_2$ this reaction a decomposition reaction in which a single nitrogen dioxide decomposes to give oxygen gas and nitrogen gas as a product.

While the other reactions,

$2NH_3+H_2SO_4\rightarrow (NH_4)_2SO_4$ this reaction is a combination reaction in which the two or more molecules combine to form a larger single molecule as a product.

$2NaBr+Ca(OH)_2\righatrrow CaBr_2+2NaOH$ this is a double displacement reaction in which the cation and the anion of the two reactant exchange their places to give two another compounds as a product.

$3Pb+2H_3PO_4\rightarrow 3H_2+Pb_3(PO_4)_2$ this is a single displacement reaction in which the more reactive metal displaces the least reaction metal from its compound.

Hence, the decomposition reaction will be, $2NO_2\rightarrow 2O_2+N_2$