JAMB - Chemistry (2019 - No. 2)
Which of the following will give a precipitate with an aqueous solution of copper (I) chloride?
But-2-ene
But-1-ene
But-2-yne
But-1-yne
Explicació
A hydrocarbon that will produce a red precipitate when reacted with an aqueous solution of copper(I) chloride is an alkyne. More specifically, an alkyne with a terminal triple bond, like ethyne (acetylene), will react to form a red precipitate of copper(I) acetylide. The most reactive alkynes are those where the triple bond is at the end of the carbon chain (terminal triple bond).