Answer:
1) first order
2) zero order
3) second order
Explanation:
For a first order reaction, the concentration of the reactants varies exponentially with the rate of reaction. The curve of a first order reaction shows an exponential relationship between the rate of reaction and the change in the concentration of reactants.
For a zero order reaction, the rate of reaction is independent of the concentration of the reactants. So, regardless of the amount of reactant in solution, the rate of reaction is constant.
For a second reaction, the reaction rate increases in direct proportion to the concentration of the reactant in solution.
Answer: Read Explanation
Explanation: Index fossils are useful because they tell the relative ages of the rock layers in which they occur. Geologists use particular types of organisms, such as trilobites, as index fossils.
Answer: potential energy is stored
Explanation:
Physical Change: It is a type of change in which matter changes its physical state like shape, size but is not transformed into another substance. It is usually a reversible process.
Chemical Change: It is a type of change in which the rearrangement of atoms of one or more than one substance is involved. and it changes its chemical composition that is there is a formation of at least one new substance. It is usually an irreversible process.
Now, keeping in mind the definitions, we can easily classify the examples in the question as physical or chemical change.
7. Chemical Change
8. Chemical Change
9. Physical Change
10. Chemical Change
11. Physical Change
12. Physical Change
13. Chemical Change
14. Physical Change
15. Chemical Change
16. Physical Change
17. Chemical Change
18. Chemical Change
19. Physical Change
20. Physical Change
21. Chemical Change
22. Physical Change
23. Chemical Change
24. Chemical Change
25. Physical Change