Which of the following demonstrates a chemical change?(1 point)
Responses
sugar and water mixing to create sugar water
sugar and water mixing to create sugar water
dry ice vaporizing
dry ice vaporizing
iron (Fe) reacting to water((H2O)) and oxygen(O) to form iron oxide(Fe2O3)
iron (Fe) reacting to water(open paren cap h sub 2 cap o close paren) and oxygen(O) to form iron oxide(cap f e sub 2 cap o sub 3)
steam condensing on a mirror
steam condensing on a mirror
The option that demonstrates a chemical change is:
- iron (Fe) reacting to water (H2O) and oxygen (O) to form iron oxide (Fe2O3)
In this reaction, iron reacts with water and oxygen to produce a new compound, iron oxide. This is a chemical change because the original substances are chemically transformed into a different substance with new properties.
The correct answer that demonstrates a chemical change is:
- Iron (Fe) reacting with water (H2O) and oxygen (O) to form iron oxide (Fe2O3)
To determine whether a change is a chemical change, we can look for the formation of new substances or a change in the chemical composition of the substances involved. In this case, the reaction between iron, water, and oxygen results in the formation of a new substance, iron oxide. This indicates a chemical change.
Let's go through the other options to understand why they do not demonstrate a chemical change:
- Sugar and water mixing to create sugar water: This is a physical change, not a chemical change. Sugar dissolves in water to form a homogeneous mixture, but the chemical composition of both substances does not change.
- Dry ice vaporizing: This is also a physical change. Dry ice, which is solid carbon dioxide, undergoes sublimation, turning directly from a solid to a gas. However, the chemical composition of the dry ice remains the same.
- Steam condensing on a mirror: This is another physical change. The steam, which is water vapor, cools down and condenses when it comes in contact with the cool surface of the mirror. Although it changes its state from gas to liquid, the chemical composition of the water does not change.
Therefore, the only example among the given options that demonstrates a chemical change is the reaction of iron, water, and oxygen to form iron oxide.