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

PHYSICAL PROPERTIES Color

Luster – shiny, dull Odor – describes the smell State of Matter – solid, liquid, gas

aka: Phase of Matter Texture – rough, smooth

Mass – describes how much material is in an objectTool: triple-beam balance

Volume – describes how much space the object takes upTools: ruler or graduated cylinder (water displacement)

Density – describes how much mass is in the objects’ volumeFormula: Density = mass ÷ volume

PHYSICAL PROPERTIES

Buoyancy – describes if the material will float in water Sinks = not buoyantFloats = buoyant Magnetic – if the

material attracts other metalsParamagnetic- attraction to magnets transition metals, rare earth

metals, actinides

Diamagnetic- repulsion to magnets

PHYSICAL PROPERTIES

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!”

Baffl ed, 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

ARCHIMEDES

Malleable – if the material can be pounded, rolled, or bent into a new shape Ductile – if

the material can be pulled or stretched into a rope or wire

PHYSICAL PROPERTIES

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

Boiling Point- (phase transition) temperature a substance goes from liquid to gas

PHYSICAL PROPERTIES- PG 12

Conductivity- ability to transmit heat, electricity, or sound

PHYSICAL PROPERTIES

Solubility- ability to dissolve or be dissolved

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 waterpHflammability (able to catch fire)

toxicity (able to be poisonous)

radioactivity (spontaneously emitting energy)

sensitivity to lightcauses newspaper to turn yellow)

When elements are arranged in

order of increasing

atomic number, their physical and chemical

properties show a periodic pattern.

HOMEWORK: PKT 9 PAGE 12 -- ELEMENT INVENTORY: ELEMENTS &

COMPOUNDS USED IN EVERYDAY LIVINGFind 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”

Common Name

Chemical NameElement Name

Symbol

Red Powerade

Magnesium chloride

Magnesium Mg

Red Powerade

Magnesium chloride

Chlorine Cl

Red Powerade

Potassium citrate Potassium K

Red Powerade

Calcium chloride Calcium Ca

Red Powerade

Potassium phosphate

Phosphorus P

Experiment with describing physical properties of various elements

Diff erent 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 stationTable available for extra items you don’t want to carry!

Color- not “copper” colored

Classification- use PT

Volume- use ruler cm3

Density = m/vBuoyancy- 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!

PHYSICAL PROPERTIES LAB- PAGE 13

FINISH LAB STATIONS: PAGE 13CONCLUSION QUESTIONS: PAGE 14ACC: CALCULATING % ERROR …FOR

DENSITY…

Element Accepted Value for Density (g/cm3)

Nitrogen 0.001145 g/cm3

Aluminum

2.70 g/cm3

Zinc 7.14 g/cm3

Tin 7.265 g/cm3

Iron 7.87 g/cm3

Nickel 8.90 g/cm3

Copper 8.96 g/cm3

Lead 11.3 g/cm3

|calculated value – accepted value|

accepted value

x 100 = % error

1. What do vinegar, lemons, and green apples have in common?

2. What do soaps, shampoo, and detergents have in common?

1. Vinegar, lemons, and green apples have a sour taste and they are acidic

2. 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.

BELLWORK: THURSDAY

3/15/12 IT…

Ion– an atom that carries a charge because it has lost or gained an electronAtom 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.

ACIDS & BASES- PAGE 15

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- A Negative ION; gained electronsEx: Chlorine (Cl) can be an anion because it easily gains an electron to become stable as Cl-

Ex. Element X as an anion: X-

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 sourReact 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

ACID

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 alkalineCharacteristics of Bases:

Taste bitterFeel slipperyStrong bases are very dangerous and can burn your skin

Examples: lye (Sodium Hydroxide- NaOH)Ammonia

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

WHAT DO YOU THINK HAPPENS WHEN YOU ADD AN ACID TO A BASE?

+

HCl + NaOH H2O + NaCl

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

HOW CAN YOU TELL THE

DIFFERENCE BETWEEN AN ACID

AND A BASE?

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 VS. BASES (PH SCALE)

Acids are materials that have a higher concentration of H+ ions

They are measured from 0-6.9 on the pH scale

PERIODIC TABLE CROSSWORD PUZZLES-

PACKET 9, PAGES 18-19

Finish fi lling 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)

1. What is the charge of an electron?

2. 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’3. 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’4. What would you call a

substance with the same amount of H+ and OH- ions?

1. Negative2. More negative charge-

makes the atom negative Negative Ion = Anion Cl-

3. Lose negative charge- makes the atom positive

Positive Ion = Cation Na+

4. Neutral!

BELLWORK: FRIDAY 3/16/2012

1. Why is it important to keep your goggles and lab apron on at all times?

2. 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?

1. They will protect from any chemicals splashing up into your eyes or on your body.

2. 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.

ACIDS & BASES LAB

Goals/Objectives Steps through Lab NOW: Make

Predictions on Data Table

Completing the data collection chart

Conclusion Questions Extension Questions

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

ACIDS AND BASES LAB- PAGE 16

1. Why do you think you were asked to include HCl and NaOH in a test of household products?

2. Lemons and oranges have nearly the same acidity and pH. Why might it be easier to eat an orange than a lemon?

3. What did you notice about the pH of distilled (purified) water vs. tap (sink) water? Why is there a difference?

4. Why do you suppose that most body fluids (i.e. saliva, blood, tears) have a pH that is neutral/almost neutral?

ACIDS AND BASES CONCLUSION QUESTIONS

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.

EXTENSION QUESTION- DUE TUESDAY 3/20

Name of Substance

Tested

What is the substance used for?

Results: pHResults:

acid/neutral/ base

Litmus Paper