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?

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 Quick Fact #23

Science Trivia What word means: the thickness of a liquid and how slowly or quickly it will pour? Velocity Variety Viscosity Valencia Volume

Owl Pellet Scores Data Chart Possible 15 Name Written Down for off task Minus 5 Not Ready at beginning of Class Worked efficiently to get to Analysis Questions Owl Pellet Wkst. on 1st day Skeleton Layout 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 Erosion of limestone and marble buildings and statues