Answer:
A - Compound
B - Compound
C - Element
D - Mixture
E - Mixture
Explanation:
A is a compound. Reaction with oxygen is called combustion and it yields new products which cannot be separated to give back its reactants. This is a property of compounds only
B is a compound. Compounds undergo decomposition and new products are formed, the original reactant can't be recovered.
C is an element. C has magnetic properties hence it is a metal and an element. Elements do not decompose into simpler forms
D is a mixture. It has 2 phases which are not homogeneous. Mixtures are easily separated into their individual components.
E is a mixture. Chromatography is a separation technique of mixtures
