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Acids and Bases are EVERYWHERE!. All liquids are either basic or acidic . You learned what a liquid is in 6 th grade Examples of liquids include shampoo, soda, coffee, drinking water, and orange juice. Anything that can be poured (slowly or fast) is a liquid.
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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? • Velocity • Variety • Viscosity • Valencia • Volume
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…
Acid eroding rock Erosion of limestone and marble buildings and statues