Question

A greenish yellow gas reacts with an alkali metal hydroxide to form a halate which can be used in fire works and safety matches. The gas and halate respectively are

• A. $Br_{2},KBrO_{3}$
• B. $Cl_{2},KClO_{3}$
• C. $I_{2},NaIO_{3}$
• D. $Cl_{2},NaClO_{3}$

Answer 1

Answer: (B)

The gas is $Cl_2$ and the halate used in fire works and safety matches is $KClO_{3}$
$\underset{\text{greenish yellowgas}}{3 C l_{2}}+6KOH \rightarrow \underset{\text{pot.chlorate (Halate)}}{K C l O_{3}}+5KCl+3H_{2}O$
As bromine is reddish liquid and $I_{2}$ is violet solid so they are ignored here.