Page 12- Physical Property - A property that can be observed with the senses, without altering or destroying the objec

1. Page 12- Physical Property- A property that can be observed with the senses, without altering or destroying the object • Observed by taste, sight, sound, touch, smell • The substance is not chemically changed to a new substance when you observe a physical property

2. Physical Properties • Color • Luster – shiny, dull • Odor – describes the smell • State of Matter – solid, liquid, gas • aka: Phase of Matter • Texture – rough, smooth

3. Physical Properties • Mass – describes how much material is in an object • Tool: triple-beam balance • Volume – describes how much space the object takes up • Tools: ruler or graduated cylinder (water displacement) • Density – describes how much mass is in the objects’ volume • Formula: Density = mass ÷ volume

4. Physical Properties • Magnetic – if the material attracts other metals • Paramagnetic- attraction to magnets • transition metals, rare earth metals, actinides • Diamagnetic- repulsion to magnets • Buoyancy – describes if the material will float in water • Sinks = not buoyant • Floats = buoyant

5. Archimedes • Baffled, Archimedes took a bath and observed the rise of water—he thought he could calculate the volume of the gold crown by water displacement! • Archimedes Principle • An object immersed in a fluid experiences a buoyant force equal to the weight of the fluid it displaces • Determines the volume of an object with an irregular shape • Task: Determine whether King Hiero's goldsmith was replacing gold with a cheaper metal during the manufacture of a gold wreath crown. • First Idea: Melt the irregularly shaped crown and crush it into a cube shape, calculate the volume, compare to the mass; find density! • Problem: King does not approve—“Solve the problem without damaging the crown!”

6. Physical Properties • Ductile – if the material can be pulled or stretched into a rope or wire • Malleable – if the material can be pounded, rolled, or bent into a new shape

7. Physical Properties- pg 12 • Boiling Point- (phase transition) temperature a substance goes from liquid to gas • Freezing Point- (phase transition) temperature a substance goes from liquid to solid • Melting Point- (phase transition) temperature a substance goes from solid to liquid; Freezing point = melting point

8. Physical Properties • Conductivity- ability to transmit heat, electricity, or sound • Solubility- ability to dissolve or be dissolved

9. Chemical property- one that indicates how a substance reacts with something else • The substance is chemically changed to a new substance when you observe a chemical property • ADD MORE EXAMPLES: • oxidation (able to react with oxygen) • apple slices to turn brown • iron rusts • heat of combustion • reactivity with water • pH • flammability (able to catch fire) • toxicity (able to be poisonous) • radioactivity (spontaneously emitting energy) • sensitivity to light • causes newspaper to turn yellow)

10. When elements are arranged in order of increasing atomic number, their physical and chemical properties show a periodic pattern.

11. Homework: Pkt9 Page 12 -- Element Inventory: Elements & Compounds used in everyday living • Find examples of at least 4 different elements and compounds listed in the ingredients list on foods, cleaners, household items, etc. • There are many names which you will not recognize—look for element names within the name of the chemicals—do not just choose “Iron”

12. Physical Properties Lab- Page 13 • Color- not “copper” colored • Classification- use PT • Volume- use ruler • cm3 • Density = m/v • Buoyancy- take element to water trays in back • Magnetic- do not break magnet in half! • Malleable- do not destroy my elements, if they bend, they are malleable! • Experiment with describing physical properties of various elements • Different element at each table • 4 minutes per rotation- counterclockwise • Put all objects (elements, magnet, calculator, rulers) back in tray before leaving • Take ALL personal belongings with you to next station • Table available for extra items you don’t want to carry!

13. Finish Lab Stations: Page 13Conclusion Questions: Page 14ACC: Calculating % Error …for density… |calculated value – accepted value| accepted value x 100 = % error

14. Bellwork: Thursday 3/15/12 it… • Vinegar, lemons, and green apples have a sour taste and they are acidic • You may have accidentally tasted soapy water, shampoo, or detergents and noted that all of these cleaning agents have a bitter taste and are basic. • What do vinegar, lemons, and green apples have in common? • What do soaps, shampoo, and detergents have in common?

15. Acids & Bases- Page 15 • Ion– an atom that carries a charge because it has lost or gained an electron • Atom with more electrons than protons – the atom becomes more negatively charged • An atom with more protons than electrons – the atom becomes more positively charged • The more electrons an atom gains or loses, the more negative or positive it becomes.

16. Cation- “Paws”itively charged ion; lost electrons • The letter t in cation looks like a positive plus sign +: ca+ion • Ex: Hydrogen (H) can be a cation because it easily loses its one valence electron to become H+ • Ex. Element X as a cation: X+ • Anion- ANegative ION; gained electrons • Ex: Chlorine (Cl) can be an anion because it easily gains an electron to become stable as Cl- • Ex. Element X as an anion: X-

17. Acid • A substance which when added to water produces hydrogen ions [H+] • The strength of an acid is based on the concentration of H+ ions in the solution. The more H+ the stronger the acid. • Characteristics of Acids: • Taste sour • React strongly with metals (Zn + HCl) • Strong acids are dangerous and can burn your skin • Examples of Acids: • Vinegar • Stomach Acid (Hydrochloric Acid- HCl) • Citrus Fruits

18. Base • A substance which when added to water produces hydroxide ions [OH-] • The greater the concentration of Hydroxide ions [OH-] the stronger the base. Ex. NaOH (Sodium Hydroxide-a strong base) in water • Basic solutions are called alkaline • Characteristics of Bases: • Taste bitter • Feel slippery • Strong bases are very dangerous and can burn your skin • Examples: • lye (Sodium Hydroxide- NaOH) • Ammonia

19. What do you think happens when you add an acid to a base? • When acids and bases are combined, a process called neutralization occurs • The acids and bases chemically react to create water (a neutrally charged substance) and a salt + HCl+NaOH H2O +NaCl

20. How can you tell the difference between an acid and a base? • pH Scale- “Potential for Hydrogen” Scale; measures acids and bases • 0 = pure acid • 7 = neutral substance • 14 = pure base • Litmus paper- indicator paper that changes colors to tell whether a substance is an acid or a base • Acids - turn the paper a shade of red/orange • Bases - turn the paper a shade of blue/green

21. Acids vs. Bases (pH Scale) • Bases are materials with a lesser concentration of H+ ions, and a greater concentration of OH- ions • They are measured from 7.1-14 on the pH scale • Acids are materials that have a higher concentration of H+ions • They are measured from 0-6.9 on the pH scale

22. Periodic Table Crossword Puzzles-Packet 9, Pages 18-19 • Finish filling in the crossword puzzles at the end of the packet! • Do your best from what you know, and use the periodic table and process of elimination to figure out the rest! • Due when you turn in your PACKET 9 next TUESDAY! (3/20)

23. Bellwork: Friday 3/16/2012 • Negative • More negative charge- makes the atom negative • Negative Ion = Anion • Cl- • Lose negative charge- makes the atom positive • Positive Ion = Cation • Na+ • Neutral! • What is the charge of an electron? • If an atom gains an electron, what happens to the charge of that atom? • What is it called? • Write Chlorine (Cl) after gaining an e’ • If an atom loses an electron, what happens to the charge of that atom? • What is it called? • Write Sodium (Na) after losing an e’ • What would you call a substance with the same amount of H+ and OH- ions?

24. Acids & Bases Lab • They will protect from any chemicals splashing up into your eyes or on your body. • Water is usually neutral (pH 7). Adding lots of water to the acid or base will neutralize any of the corrosive material that has gotten on your skin, and will dilute the strength of the acid or base so that it will not burn or irritate you. • Why is it important to keep your goggles and lab apron on at all times? • Why is it important to use lots and lots of water if you accidentally spill an acid or a base on your skin/in your eyes?

25. Acids and Bases Lab- Page 16 • Work in pairs • 14 stations • NaOH and HCl with Mrs. Cole • 1 ½ minutes at each station • Stay at your station • Take tray with you to each station • Only 1 drop/substance • Record pH values of the substances • Time’s up? Move quickly and quietly to the next station • Stay on chair-less side of table • Change aprons at halfway point • Goals/Objectives • Steps through Lab • NOW: Make Predictions on Data Table • Completing the data collection chart • Conclusion Questions • Extension Questions

26. Acids and Bases Conclusion Questions • Why do you think you were asked to include HCl and NaOH in a test of household products? • Lemons and oranges have nearly the same acidity and pH. Why might it be easier to eat an orange than a lemon? • What did you notice about the pH of distilled (purified) water vs. tap (sink) water? Why is there a difference? • Why do you suppose that most body fluids (i.e. saliva, blood, tears) have a pH that is neutral/almost neutral?

27. Extension Question- DUE TUESDAY 3/20 • Take home 1 strip of litmus paper and, paying close attention to the safety warnings on each substance, test the pH of liquid substances in your cupboards and cabinets. Fill in the chart and tape or glue your litmus strips in the appropriate column, when they are dry. • Tear the strip into 6 pieces • Do tests for 6 items • ACC ONLY: Design an experiment similar to the one completed in class to determine the pH values for solid household substances, such as: antacid tablets, uncoated aspirin tablets, salt, sugar, dishwashing detergent, etc. Write the procedure for how you would conduct this experiment.