Laboratory Experiement Introduction

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Name ____________________________
Period ____________
Intro to Chemistry Laboratory
Honors 9 Chemistry
At the end of this lab you will be able to:
1. Light and adjust a Bunsen burner.
2. Correctly measure a liquid in a graduated cylinder.
3. Use and tare an electronic balance.
4. Take and record meaningful observations.
5. Recognize and properly use common laboratory equipment.
Part I: Lighting and adjusting a Bunsen burner
You need to light and adjust the Bunsen burner to make the flame larger and smaller and to make
the flame yellow and blue. Once you have practiced and are completely comfortable with doing
this turn off the burner and redo procedure for your teacher.
FOR TEACHER USE ONLY:
Size:
Color:
Have Bunsen burner lit. Obtain an index card and hold it with crucible tongs on edge against the
top of the Bunsen burner until a fully established scorch pattern is observed. QUICKLY remove
the card and immediately blow out any flames. Record the scorch pattern to the left of the
burner setups and label hot and cold parts. Dispose of card.
Burner Setups
Correct Setup
Incorrect Setup
Turn off the Bunsen burner. Obtain a match and a pin. Carefully push the pin through the
match. Carefully light another match and light the Bunsen burner with it. If you do this
carefully, you will observe that the match suspended in the barrel remains unlit. Explain why
this occurs.
Explanation:
Part II: Using an electronic balance
1. Place a 100ml beaker on a digital balance. Press the TARE button to zero the balance. Pour
between 4-5 grams of copper sulfate solid into the beaker. Record the actual amount used.
TIPS:
a. NEVER return a chemical back into its dispensing container that could
contaminate the class material.
b. Be sure the balance has a "g" in the corner signaling it is measuring in grams.
MASS OF COPPER SULFATE = _________grams
Part III: Take and record meaningful observations:
2. Pour some of the copper sulfate solid from the above section onto a piece of paper and
observe its properties. Use a magnifying glass to make closer observations. Pour the copper
sulfate back into the beaker. Bring a magnet up against the OUTSIDE of the beaker. Record all
the properties.
3. Obtain a 50ml beaker and pour between 1-2g of iron filings into the beaker. Remember to
use the tare button. Record the actual amount of iron used.
MASS OF IRON USED: ______________grams
4. Observe properties of iron.
PROPERTIES of copper sulfate:
PROPERTIES of iron:
Part IV: Measuring a Liquid witha graduated cylinder
5. Using a graduated cylinder, measure 25 ml of distilled water.
TIPS:
a. Stand with cylinder on table and determine amount of liquid.
b. Get down to water level and determine amount of liquid.
c. Get further down below the level and determine amount of liquid.
VOLUME OF WATER:
Stand tall and read the level of water
________________ ml
Stand so that your eyes are level with the water
________________ml
Squat so that your eyes level with the table and read the level of water
________________ml
Part V: Heating a Liquid
6. Pour the water measured above into the beaker containing the copper II sulfate solid and stir
7. Place the beaker on wire gauze that is resting on an iron ring. The iron ring is connected to a
ring stand. Heat the solution until it just begins to boil. When it boils turn off the
burner and stir. Observe the properties.
Properties:
8. While stirring the hot solution with a glass rod, add the iron filings a little at a time. Allow 10
minutes for the reaction.
9. Carefully decant the solution. Decant means to pour off the liquid into another beaker leaving
the solid behind. Wash the solid several times with tap water. Use about 10 mL
of water each washing and carefully decant after each washing.
Use beaker tongs to remove a beaker from the stand. Use crucible tongs to
remove a smaller item like a crucible, a watch glass, etc.
crucible tongs
beaker tongs
10. Observe the solid in your beaker. Bring a magnet up against the outside of the beaker. DO
NOT allow magnet to touch any of the substance directly. Observe the properties.
Properties:
11. Dispose of all solids in the bucket in the vent hood. All liquids may go into the sink with
water.
Analysis:
1. What part of the flame is hottest; what evidence do you have to support that?
2. What color flame is hottest?
3. Does step 6 involve a chemical or physical change? Explain. (Hint: use your textbook)
4. Does step 8 involve a chemical or physical change? Explain using evidence.
(Hint: use your textbook)
5. What are the following pieces of equipment?
a.
b.
6. What do you think would happen if you put the solid into the sink at the end of the lab?
7. What do you think you made as your final product? What evidence do you have of that?
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