Look at the pictures below.
Forest Fire:
Fire in progress
Fire extinguished
Claim - Is this a chemical change or a physical change?
(1 point)
Responses
Chemical change
Chemical change
Physical change
Physical change
Evidence - What observations about the forest fire support your claim? Answer the question with one or more complete sentences to receive full credit. Optional - Use a sentence stem from the "Evidence" Box below.
Observations of the forest fire support the claim that it is a physical change because there is no evidence of a new substance being formed. The fire is simply a result of the combustion of organic matter, which involves a physical transformation of the materials involved rather than a chemical reaction.
Reasoning - How does your evidence support your claim about the forest fire? Answer the question with one or more complete sentences for full credit. Optional - Use a sentence stem from the "Reasoning" Box below.
The evidence of the forest fire being a physical change is supported by the absence of any new substances being formed during the fire. In a chemical change, new compounds or molecules are typically produced, but in the case of a forest fire, the materials involved (such as trees and vegetation) are simply undergoing a physical transformation due to the release of heat and the conversion of organic matter into ash and smoke. Therefore, the lack of any chemical reactions or the formation of new substances supports the claim that the forest fire is a physical change.
Based on the provided information and pictures, the process of a forest fire involves the burning and combustion of plant materials. This indicates that it is a chemical change rather than a physical change. Therefore, both pictures show a chemical change.
To determine if a process is a chemical change or a physical change, we need to understand the difference between the two.
A physical change refers to a change in the physical state or appearance of a substance, where no new substances are formed. In other words, the chemical composition of the material remains the same before and after the change. This can include changes in size, shape, texture, or phase (like solid to liquid or liquid to gas). An example of a physical change would be freezing water into ice cubes or melting wax.
On the other hand, a chemical change involves the rearrangement of atoms and the formation of new chemical substances. This means that the chemical composition of the material changes, resulting in different properties and characteristics. For example, when a log burns in a fire, it undergoes a chemical change because new products like ash, carbon dioxide, and water vapor are formed.
Now, looking at the pictures you provided, we see a forest fire in progress and then the fire being extinguished. In this case, we can conclude that the process is a chemical change. The reason is that during the fire, the substances in the forest (such as trees and vegetation) are being burned and converted into new substances like ash, smoke, and gases. The fire extinguishing process involves the removal of the fuel source and suppression of the chemical reactions, thus stopping the chemical change.
So, the correct answer to the question is: Chemical change.