1. Which of the following items represents a chemical change? burning melting evaporation freezing
Answer:
- Chemeical change: Burning
- Physical change: melting evaporation freezing
Explanation:
Chemical properties depend on composition while physical properties do not depend on composition. As in case of burning, composition changes due to this , this is chemical properties while freezing, melting and evaporating process, composition remain same, so these have physical properties, like water in liquid, ice and vapor state have same composition.
2. The physical properties of a compound are similar to those of its elements.
Answer:
Explanation:
- The properties of compounds are often very different from the properties of the elements that make them. For example, water is made from two atoms of hydrogen bonded to one atom of oxygen. H2O have different physical properties than oxygen and hydrogen.
