It is an example of a physical change because the chocolate changes from a solid to a liquid however it’s chemical composition is not changed so it’s a physical change.
Each layer has a unique chemical composition, physical state, and can impact life on earths surface. Movement in the mantle caused by variations in heat from the core, causes the plates to shift, which can cause earthquakes and volcanic eruption‘s.
Answer: Conductor
Explanation: A material that conducts thermal energy well is called a thermal conductor.
<span>With any element, there are a range of isotopes . . . a weighted average mass is used because there exist different isotopes of that element, each of varying mass. A weighted average accounts for the fact that the average mass (that may likely be measured from a random sample of the element) will most likely reflect the average mass of the more abundant isotopes. So the weighted average mass will be most comparable to the more abundant isotopes.</span>