he showed that oxygen is required to burn.
<span>The pairs of substances I would expect to form homogeneous solutions when combined will form a homogeneous because both are polar and form dispersion forces, dipole-dipole and hydrogen bonding between the water molecules and ion-dipole forces between the K+ and Cl- ions and the water molecules.</span>
The melting of the ice cube indicates physical change has taken place
A phosphorus atom and a chlorine atom are likely to form a covalent bond because both elements are nonmetals.
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.