Physical and Chemical Changes PDF

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Summary

chemistry class work that might help you...

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Physical and Chemical Changes Lab Report Introduction: My goal in the lab was to determine the difference between physical and chemical changes. In the lab we did 9 different tests mixing or adding heat to chemicals or substances and seeing if their changes were physical or chemical. Well the question is how can you tell if it is a chemical or physical change? I believe that you can tell if it's a physical change when the object or substance does not change because you can tell if it's a chemical change when the object or substance does change. Materials and Procedure: The materials we used for this procedure were calcium carbonate, mortar and pestle, 3 spoons, hydrochloric acid, 3-50mL beakers, 1-100mL beaker, hot plate, hot pad,copper sulfate, crucible, crucible tongs, clay triangle, tripod, bunsen burner, iron filings, sulfur, petri dish, magnet, potassium iodide, lead nitrate, graduated cylinder, magnesium ribbon, thermometer, tweezers, candle and a match. After I collected my materials I just completed the procedure as it said to the student guide. In this procedure since we used so many different substances and chemicals there were not controlled or independent variables in this experiment. Data collection and organizing: Step

Material

Change(s) observed

Type of change (physical/chemical)

Reasoning

2

Calcium carbonate

Now powder

physical

No reaction happen it changed its form

3

Calcium carbonate and hydrochloric acid

Changed color

chemical

Started to develop a gas after dissolving calcium carbonate

4

Water

Heat just changed

physical

Stayed the same after heat was added

5

Copper Sulfate pentahydrate

Changed color turned into gas

chemical

Turned into gas because of its reaction with heat

6

Iron filings and

Changed color

physical

Its physical

sulfur

because when we used the magnet the two substances separated easily which means they never changed form

7

Lead nitrate and potassium iodide

Changes color and formation

chemical

Created a new gas producing substance

8

Magnesium and hydrochloric acid

Color changed

chemical

The one object dissolved in which making it a chemical reaction

9

Candle

Melted

both

The wax melts but is still the same substance by which gas is being produced from the flame burning the candle.

Analysis and Conclusion: In this lab I learned the difference between physical and chemical changes by mixing different chemicals and adding heat to specific objects to see their reaction. After completing this lab I have learned to be able to tell the difference between the two reactions. Physical reaction is when an object stays the same and no reaction occurs. Chemical reaction being when an object or chemicals have a reaction or something changes. Something i can improve from this lab is to do more experiments to see more examples of chemical and physical change....