JAMB - Chemistry (1985 - No. 18)
A colourless organic compound X was burnt in excess air to give two colourless and odourless gases, Y and Z, as products. X does not decolorize blue bromine vapour, Y turns lime milky while Z gives a blue colour with copper (ll) tetraoxosulphate (IV).
Compound X is?
Compound X is?
an alkene
an alkane
an alkyne
tetrachloromethane
dichloromethane
Shpjegimi
Burning the alkane in the presence of sufficient air or oxygen; it produces carbon dioxide, water, and a huge amount of heat as a product.
If carbon dioxide is bubbled through limewater, the limewater turns milky or cloudy white.
Anhydrous CuSO4 is used to test the presence of water in any liquid because it changes its colour from white to blue in the presence of water.