Question

When few drops of dil. $HCl$ are added to a small amount of red copper oxide, the colour of the solution becomes:

• A. Blue
• B. Green
• C. Pink
• D. Yellow

Answer 1

The correct option is A Blue

When few drops of dil. $HCl$ is added to a small amount of red copper oxide, the colour of solution becomes blue due to the formation of chloride of copper $CuC{l}_2$.
$CuO+2HCl\to CuC{l}_2+H_{2}O$