JAMB - Chemistry (2021 - No. 6)
A 'breath test' used by traffic police to check drunken driving uses?
Tumeric on filter paper
Silica gel coated with saliva nitrate
Potassium permanganate-sulphuric acid
Potassium dichromatic-sulphuric acid
Wyjaśnienie
The earliest developed breathalyzer was based on reaction of alcohol if present in the exhaled air with a cocktail of chemicals containing sulfuric acid, potassium dichromate, silver nitrate, and water. Silver nitrate catalyzes the reaction between alcohol and potassium dichromate in acidic medium.