The explanations are mentionned in the attached file.
1. The right answer is physical changes.
2. The right answer is chemical changes.
3. The right answer is chemical change.
4. The right answer is fireworks exploding.
5. The right answer is All of the above.
6. The right answer is combining oxygen gas and hydrogen gas to form liquid water.
7. The right answer is gas is produced.
8. The right answer is The compound may or may not be poisonous, depending on the chemical properties of the new substance.
9. The right answer is This is a physical change, because the two substances were separated physically by boiling.
10. The right answer is C. The tablet that was placed in the water interacted ... chemical change.
11. The right answer is B. Energy is either released or absorbed.
12. The right answer is that we should compare both physical and chemical properties of these two substances : if they have the same properties, it means that it is the same substance, if not, they are different substances.
13. The right answer is A. Flammability.
14. The right answer is Column.
15. The right answers are Melting point, conductivity, solubility, malleability, density.
16. The right answer is oxidation, flammability, combustibility.
17. The right answer is A. Arrangement of protons in the nucleus.