Question

what do these two changes have in common?
a dinosaur bone turning into rock over millions of years
a slice of banana turning brown
select all that apply.
both are only physical changes. both are chemical changes.
both are caused by heating. both are caused by cooling.
submit

Explanation:

A dinosaur bone turning into rock over millions of years is a chemical change as new substances are formed through processes like mineral replacement. A slice of banana turning brown is also a chemical change due to oxidation reactions (a type of chemical reaction) that change the chemical composition of the banana. Physical changes only change the state or appearance of a substance without altering its chemical composition. Heating or cooling are not the causes for these specific changes - the dinosaur bone fossilization is due to geological and chemical processes over time, and banana browning is due to enzymatic oxidation (a chemical reaction that can occur at room temperature, not specifically because of heating or cooling).

Answer:

Both are chemical changes.