Exploring Changes in Matter

1. We were trying to answer the question "Which changes are examples of a chemical change, and which are examples of a physical change." We want to answer this question because physical and chemical changes have different properties that tell them apart, which we are trying to answer.

2. During our investigation we mixed and heated multiple different kinds of elements to see the changes it caused. We conducted this way because it gave us obvious answers to our question.

3. Claim: Something new and different that wasn't there before is an example of a chemical change. When it stays the same and nothing changes it is an example of a physical change.

Evidence:
Water & salt = Salt disappeared
Copper & heat = color changed
NaOH & CuNO32 = became a solid
HCl & NaHCO3 = Fizzed
Wax & hot water = liquid from a solid
Reasoning:
•Salt & water was a phys. change because the salt only disappeared because they were mixed so nothing new came about.
• Copper & heat was a chem. change because the color changed from Copper > Siver so there was something new.
• NaOH & CuNCO3 was a chem. change because it became a gel like substance when before it was a liquid so there is something new.
• NCl & NaHCO3 was a chem. change because the solution fizzed but when they were liquid they did not frizz so it's something new.
• Wax & hot water was a phys. change because the wax was a solid then a liquid so nothing new came about just the physical appearance.

Comments

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