Answer:
A.
Explanation:
The potential energy of the roller coaster increases as the coaster goes up a hill and can be converted to kinetic energy.
Mendeleev organized his periodic table in order of increasing atomic number in 1869.
A. Identify the properties as either a physical or chemical property. (first 3 are chemical, last is physical)
Answer:
The two valid principles are:
- Scientific theories can be replaced by better theories.
- An experiment can disprove a theory that scientists have accepted.
Explanation:
The scientific knwoledge is not inmutable; it may (and does) change with new discoveries.
In fact, scientific theories cannot be proved right, instead they are constantly tested to try to disprove them. This is what the principle that theories are falsiable means.
As long as a scientific theory is not disproved it remains valid, but new discoveries may lead, eventually, to its disprovement.
Scientific knowledge evolves because new procedures, new technologies, and new evidence leads to a better understanding and better explanations.
