Acids and Bases are EVERYWHERE!

• All liquids are either basic or acidic.• You learned what a liquid is in 6th grade• Examples of liquids include shampoo, soda,

coffee, drinking water, and orange juice.• Anything that can be poured (slowly or fast)

is a liquid.• Let’s understand what it means to be basic

or acid…..

Acidic

• In your body there are small compounds called amino acids. Those are acids.

• Citric acid is found in fruits. That’s an acid, too.

• Vinegar? Also an acid.

• Acidic means a solution has an excess of positive hydrogen ions.

Basic

• Baking soda, drain cleaner, and sodium hydroxide (NaOH) are all bases

• Another word for base is alkali

pH Scale• Scientists use the pH Scale to measure how acidic or basic a liquid

is.• pH test strips are used. • A strip is placed in a liquid and the strip changes color. The new

color can be matched up to the pH Scale to determine how acidic or basic the liquid is.

Acid or Base?

• If the strip matches the scale between the numbers 1-6, the liquid is acidic.

• If the strip matches the scale between the numbers 8-14, the liquid is basic.

• Distilled water will be the only liquid that matches up exactly to 7, and this means the liquid is neutral (neither acidic or basic).

Litmus test• Besides pH test strips, Litmus

paper strips are also used to indicate whether a liquid is a base or an acid.

• Blue litmus paper (purplish) turns blue if the liquid is a base, and turns red if the liquid is an acid.

• Red litmus paper (pinkish) turns red if the liquid is an acid, and turns blue if the liquid is a base.

• Is the liquid in the photo an acid or a base?

Science Quick Fact #23

Distilled water is water that has all of its impurities removed through distillation. Therefore, it will always have a pH level of 7 which is neutral.

Distillation involves boiling the water and re-condensing the steam into a clean container, leaving most if not all solid contaminants behind.

Science Trivia

What word means: the thickness of a liquid and how slowly or quickly it will pour?

A.Velocity

B.Variety

C.Viscosity

D.Valencia

E.Volume

Owl Pellet Scores

Data ChartPossible 15

Name Written Down for off task

Minus 5

Not Ready at beginning of Class

Minus 5

Worked efficiently to get to Analysis Questions

OwlPellet Wkst. on 1st day

Possible 15

SkeletonLayout with over 20 labels

Possible 20

Name written down for something positive

Plus 5

TOTAL

• Look Over Owl Pellet Scores: incompletes need to see me!• If you do not have safety goggles today, you cannot handle any of

the strips or liquids• Need to have out insert #24!• Need to have created your SMART goal on insert #13• Need to have completed Unit 2 pre-test on insert #26 (let me

know if you haven’t received this): Give to Mrs. Kinley• Need 26 entries in your TOC

22. Student Grade Report

23. Unit 2 Power Point Notes

24. Acids and Bases Lab

25. Acids and Bases Notes

26. Unit 2 Pre Test

ACIDS & BASES quiz tomorrow: TAKE HOME NOTES! (see me about missing notes)

Today’s Lab• One lab worksheet with columns that need

to be filled out and questions to be answered.

• Stations that include– a liquid (do not spill, touch, taste, or smell)– pH test strips– pH scale color indicator on the side on the

container– blue and red litmus paper– paper toweling

Procedure• You will work in groups of four• You will rotate around the room to each station• At each station you will put down a sheet of paper

toweling• One member will test the liquid with a pH test strip.• One member will test the liquid using litmus paper• One member will determine the pH number according to

the pH scale and the test strip color• One member will dispose of the used paper toweling and

strips• At the next station, you will follow the same steps, but

rotate jobs as well.• All lab questions need to be answered individually as

homework.

pH Test: match strip color to side of tube ontainer

Litmus Paper Test:

Blue Blue = BASE

Blue Red = ACID

Red Blue = BASE

Red Red = ACID

Any Questions????

Let’s Begin!

REVIEW

• Is vinegar an acid or a base?• Baking soda?• What about lemon juice?• HCl? NaOH?• What is neutral (number and liquid?)• What do we use to test acidity?• What scale do we use?• Red strip turning blue means what?

Acid Rain: The Photo Story

Chemicals into the air…

chemicals + sun + water vapor = acid!

Acid Rain

After the rain…

Why more acid rain here?

pH tolerance levels of freshwater animals

The result…

Erosion of limestone and marble buildings and statues

Acid eroding rock