Let's address each of your numbered questions:
-
A large piece of metal is sitting in a solid form. Heat is applied to it until the metal melts. What property in the metal is changed during this process?
B the average kinetic energy of the metal atoms
During melting, the heat energy increases the average kinetic energy of the metal atoms, causing them to move more freely, which leads to the transition from solid to liquid. -
Which of the following describes the process of melting?
A Au(s) → Au(l)
This describes the transition of solid gold (Au) into liquid gold (Au) when heat is applied. -
Which of the following is the best example of chemical energy being converted into thermal energy?
A hydrogen turning into helium inside the Sun, giving off heat energy
This process (nuclear fusion) converts nuclear potential energy into thermal energy, producing significant heat and light. However, if the context is focused strictly on chemical energy (like in combustion), then B burning a candle in a room would also be a valid answer as it directly involves the conversion of the chemical energy stored in the wax into thermal energy. But since option A represents a broader conversion of energy, it can be favored in a different context.
If you need clarifications on any of these points, feel free to ask!