Answer:
The question lacks options, the options are:
A) Water turns to steam when boiled over a Bunsen burner.
B) Carbon combines with oxygen to form carbon dioxide gas.
C) Water breaks down into hydrogen and oxygen gases.
D) Limestone breaks down into lime and carbon dioxide when heated.
The answer is A
Explanation:
Changes occur from one state of matter to another. This change can either be physical or chemical. A physical change is a change in which no new substances are formed as products and it can be reversed to form the reactants again. Chemical change, on the other hand, forms new substances as products by the rearrangement of chemical bonds in the resulting molecule.
In the case of this question, water turning into steam when heated, a process called evaporation is an example of physical change because water, which is a liquid is just changing its state to gaseous (steam). Hence, no new substance is formed. The steam can easily be reversed back to water via CONDENSATION.
In the other options, new products are formed either by breaking the chemical bonds between molecules or rearranging them. Hence, options B, C and D are examples of chemical change.
