2018 acids and bases ppt - cinnaminson middle school

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How does he do this magic trick? https://www.youtube.com/watch?v=ujkuW-0cpNw&t=32s

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Page 1: 2018 acids and bases ppt - Cinnaminson Middle School

How does he do this magic trick?

https://www.youtube.com/watch?v=ujkuW-0cpNw&t=32s

Page 2: 2018 acids and bases ppt - Cinnaminson Middle School

Acids and BasesTwo special classes of compounds

Page 3: 2018 acids and bases ppt - Cinnaminson Middle School

Elements•Contain a single kind of atom

Page 4: 2018 acids and bases ppt - Cinnaminson Middle School

Compounds•Substances that are chemically formed

•They have physical and chemical properties that are different from the elements that make them up.

•They are formed as the result of a chemical reaction.

Page 5: 2018 acids and bases ppt - Cinnaminson Middle School

Hydrogen (an explosive gas) and oxygen (an explosive gas) combine to form the compound water (a harmless liquid).

Here, the hydrogen gas in the zeppelin SS Hindenburg reacts with oxygen in the air to make water.

Source: Photo courtesy of the US Navy, http://commons.wikimedia.org/wiki/File:Hindenburg_burning.jpg.

Page 7: 2018 acids and bases ppt - Cinnaminson Middle School

Acids and Bases

•Acids and Bases can be helpful or harmful.•Acids and bases can be weak or strong.•YOU MUST ALWAYS BE CAREFUL WHEN WORKING WITH ANY CHEMICALS!

Page 8: 2018 acids and bases ppt - Cinnaminson Middle School

Characteristics of Acids

•Have a sour taste (never taste an unknown!)

•They have Hydrogen atoms which have given up their electron, making them positive ions. (H+)

Page 9: 2018 acids and bases ppt - Cinnaminson Middle School

Characteristics of Acids

• They turn blue litmus paper red

•They react with metals to release Hydrogen gas.

http://www.youtube.com/watch?v=PqUOGc6P05c

Page 11: 2018 acids and bases ppt - Cinnaminson Middle School

USES OF ACIDS•Citric acid and ascorbic acid (Vitamin C) are found in orange juice

•Carbonic acid and phosphoric acid give a “bite” to soft drinks

•Acids in your stomach aid in digestion•Sulfuric acid is the most widely used industrial acid in the world. It is used in making metals, paper, paints, and fertilizers.

Page 12: 2018 acids and bases ppt - Cinnaminson Middle School

Sulfuric Acid on a Sponge

Page 13: 2018 acids and bases ppt - Cinnaminson Middle School

Characteristics of Bases

•Have a bitter taste (never taste an unknown!)

•They feel slippery

Page 14: 2018 acids and bases ppt - Cinnaminson Middle School

Characteristics of Bases

They have Hydroxide (OH) compounds which have taken on an electron, making them negative ions. (OH-)

Page 15: 2018 acids and bases ppt - Cinnaminson Middle School

Characteristics of Bases

• They turn red litmus paper blue

•They do not react with metals.

Page 16: 2018 acids and bases ppt - Cinnaminson Middle School

Uses of Bases•Bases are used in soaps (remember, bases are slippery)

•Bases are used to make paper, in oven cleaners, and to unclog drains

•Ammonia is a base and is used in many household cleaners

Page 20: 2018 acids and bases ppt - Cinnaminson Middle School

INDICATORS

•Cabbage juice can also be used as an indicator.

•The juice should turn pink in acidic solutions, and green/blue/yellow in basic solutions.

Page 21: 2018 acids and bases ppt - Cinnaminson Middle School

Turn and talk- how does he do this magic trick?

https://www.youtube.com/watch?v=ujkuW-0cpNw&t=32s

Page 23: 2018 acids and bases ppt - Cinnaminson Middle School

pH scale

•Acids and Bases are ranked on a pH scale.

•0-6.9 = acids, lots of H+ ions

•7.1-14 = bases, lots of OH- ions

Page 27: 2018 acids and bases ppt - Cinnaminson Middle School

Summary of Characteristics of Acid and Base Compounds

http://www.youtube.com/watch?v=tNvP3-174_M

Page 28: 2018 acids and bases ppt - Cinnaminson Middle School

Question #1•Lemon juice has a pH of 2.2. Is it an acid or a base?

•acid

Page 29: 2018 acids and bases ppt - Cinnaminson Middle School

Question #2•Detergents such as Tide have a pH of about 10. Is Tide an acid or a base?

•base

Page 30: 2018 acids and bases ppt - Cinnaminson Middle School

Question #3•Seawater has a pH of 8.2. Is seawater an acid or a base?

•base

Page 31: 2018 acids and bases ppt - Cinnaminson Middle School

Question #4•The inside of your mouth has a pH of 7. Is it an acid or a base?

•neutral

Page 32: 2018 acids and bases ppt - Cinnaminson Middle School

Question #5•How do you think we came up with the term “acid rain”?

•Rain water has a pH less than 7

Page 33: 2018 acids and bases ppt - Cinnaminson Middle School

Question #6•409 cleaner contains ammonia that has a pH of 12. What will 409 do to red litmus paper?

•Turn blue

Page 34: 2018 acids and bases ppt - Cinnaminson Middle School

Question #7•A soft drink has a pH of 3.2. What will it do to a piece of red litmus paper?

•Stay red

Page 37: 2018 acids and bases ppt - Cinnaminson Middle School

Question #10•What is a physical or chemical property of water?

•Liquid at room temperature, colorless, has a pH of 7 (is neutral)

Page 38: 2018 acids and bases ppt - Cinnaminson Middle School

pH of Everyday Substances

Copyright © 2005 by Pearson Education, Inc.Publishing as Benjamin Cummings

Page 40: 2018 acids and bases ppt - Cinnaminson Middle School

How can I tell if something is an acid or a base?• You can taste it (NEVER do this in a chemistry lab)

• You can find its pH using a pH test paper• 0-6 = Acid 7= water/neutral 8-14= base

• You can use an indicator• Red or blue litmus paper• cabbage juice indicator

Page 41: 2018 acids and bases ppt - Cinnaminson Middle School

Procedures• Goggles on

• Tear a piece of red litmus paper into three pieces and put them in the tray.

• Tear a piece of blue litmus paper into three pieces and put them in the tray.

• Tear a piece of orange universal pH paper into three pieces and put them in the tray.

• Drop vinegar on the first row (an acid)

• Drop water on the second row (neutral)

• Drop baking soda on the third row (a base)

• Make observations and record data

• Clean up

VinegarBaking SodaWater

Page 42: 2018 acids and bases ppt - Cinnaminson Middle School

Safety Warnings: Use your safety contract to help you.

1. Wear goggles

2. No horseplay, follow directions

3. Do not touch, taste, smell unknown liquids

4. Wear apron, roll up sleeves

5. Clean up when finished

6. Watch for broken glass, report spills

Page 43: 2018 acids and bases ppt - Cinnaminson Middle School

Record your observations and conclusions

baking soda

Page 44: 2018 acids and bases ppt - Cinnaminson Middle School

Unknown Acid/Base/Neutral Identification labWorth 25 points

Objectives: Can you use your knowledge of acids and bases to identify 3 unknown substances using indicators?

1. Follow all previous safety guidelines2. Read your procedures3. Design a data table for three unknown lettered test

tubes - get teacher initials4. Conduct your testing and record your observations5. Form your conclusions and complete review section

ABC

Page 45: 2018 acids and bases ppt - Cinnaminson Middle School

Data –what information will you collect about the three substances? Organize a chart to put the data into.

Sample A Sample CSample B

Page 46: 2018 acids and bases ppt - Cinnaminson Middle School

Writing a lab•Create a descriptive title for your experiment: __________________________________________________

•Problem: How can an unknown liquid be identified as an acid, a base, or a neutral substance?

•Background Information: Acids and bases are special classes of compounds that have their own unique characteristics. Acids are _______________tasting, have H+ ions, turn blue litmus paper _____________, and they react with ____________. Bases have a ____________ taste, feel slippery, have OH- ions, and turn red litmus paper ____________.

Page 47: 2018 acids and bases ppt - Cinnaminson Middle School

Materials: What materials do you need to complete this lab?Goggles, apron, beakers, red and blue litmus paper, sample tray, three unknown liquids, pH paper, droppers, lab sheet

Page 48: 2018 acids and bases ppt - Cinnaminson Middle School

Procedures –what are the steps you need to follow to correctly identify an unknown substance as an acid or base?

1. Gather materials

2. Goggles on

3. Clean off tray

4. Tear red litmus into three pieces and put into tray

5. Repeat with blue and pH paper

6. Drop unknown chemical (A) onto red, blue, and pH paper

7. Repeat with unknown (B) and (C) liquids.

8. Record observations

9. Clean up

Page 49: 2018 acids and bases ppt - Cinnaminson Middle School

Conclusion Statement: Following the actual performance of the lab, write a one paragraph summary about

•What you did in this lab.

•How you performed this lab (a summary)

•What you learned as a result of performing this lab.

Page 50: 2018 acids and bases ppt - Cinnaminson Middle School

Turn in by Thurs. December 11th

A formally typed or very neatly handwritten lab (ON A SEPARATE PAPER!) is due!

Page 51: 2018 acids and bases ppt - Cinnaminson Middle School

• It must include the following (40 points total possible): (LABEL EACH SECTION WITH THE APPROPRIATE TITLE)

• Title of the lab (2 points)

• Problem: describe the problem that will be solved in this lab (2 points)

• Background information: one paragraph with facts about acids and bases (5 points)

• Safety warnings: bulleted list of safety rules to be followed (5 points)

• Materials list: bulleted list of all materials needed for the lab (2 points)

• Procedures: step by step instructions (2 points)

• Data: Include your table and FILL IN THE RESULTS you collected when you tested the materials (10 points)

• Conclusion: A one paragraph summary of what you did, how you did it, and what you learned. (10 points)

• Spelling, grammar, and overall neatness will be graded as well (2 points)

Page 52: 2018 acids and bases ppt - Cinnaminson Middle School

Use the Rubric!