wednesday, sept. 5 th : “a” day thursday, sept. 6 th : “b” day agenda homework...
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Wednesday, Sept. 5th: “A” DayThursday, Sept. 6th: “B” Day
AgendaHomework Questions/Collect (Pg. 9: 1-10)Sec. 1.1 Quiz: “What is Chemistry?”Lab discussionSec 1.2: “Describing Matter”
Matter, volume, mass, weightUnits of measurement (base/derived) Conversions between unitsProperties of matter: physical & chemical
Homework: 1. Sec. 1.2 review, pg. 19: #1-11 2. Concept Review: “Describing Matter”
HomeworkPg. 9: #1-10
Questions?
Collect
Section 1.1 Quiz“What is Chemistry?”
You may use your guided notes and your book to complete the quiz……
“Lab Techniques”Lab Discussion
I just wanted to take a few minutes to go over the lab analysis/conclusion questions so that you know what I expect in future labs…
Sec 1.2: “Describing Matter”
Matter: anything that has mass and takes up space.
Sort Into: Matter, not matter, not sure.Peanut butter, water, fish, energy, garbage,
time, motion, the human brain, carbon dioxide, air, yourself, an idea, a tree.
The Space an Object Occupies is its Volume
Volume: A measure of the size of a body or region in 3-dimensional space
How to find volume:Solids: (length) X (width) X (height)
OR Liquid displacement
Liquids: graduated cylinder
The Quantity of Matter is the MassMass: A measure of the amount of matter in
an object; a fundamental property of an object that is not affected by the forces that act on the object, such as the gravitational force
How to measure mass:Balances, either mechanical or electronic
Mass is not WeightWeight: A measure of the gravitational force
exerted on an object; its value can change with the location of the object in the universe
Weight and mass are not the same thing!
Weight vs. Mass
If you were on the moon, would your mass change?
What about your weight?
Qualitative vs. QuantitativeTerms such as heavy, light, rough, and smooth
describe matter qualitatively.They describe the “quality” of matter but
DO NOT use numbers.
Scientists describe matter in quantitative terms, using numbers.They describe the “quantity” of matter.Examples: 200˚C, 15 mL, 10 sec
Quantities and UnitsQuantity: something that has magnitude, size, or amountUnit: a quantity adopted as a standard of measurement
Example: a graduated cylinderQuantity = the volume of a liquidUnit = milliliter (mL)
Units of MeasurementThe 7 BASE UNITS of measurement in the SI
system are:
“SI” stands for Systeme Internationale d’Unites
Units of MeasurementSometimes, the base units can be too big or
too small for certain measurements, so prefixes are added to the base units.
Converting One Unit to Another
Other equivalent values that you need to know…..
1 L = 1,000 mL = 1,000 cm3
1 mL = 1 cm3
Often, volumes are measured in cm3 and not mLcm3 is read “cubic centimeter” or “cc”
(think of doctor shows…I need 500 cc’s, stat!)
Converting One Unit to AnotherConversion factor: A ratio that is derived from the
equality of 2 different units and that can be used to convert from one unit to the other. **Conversion factors are fractions that are always
equal to 1**
Example: 1 dozen eggs = 12 eggs The 2 conversion factors are:
12 eggs OR 1 dozen 1 dozen 12 eggs
It’s just like you’re multiplying by 1. Multiplying by 1 doesn’t change the value, right?
Sample Problem A, Pg. 14Converting Units
Convert 0.851 L to milliliters, mL.
1.Always “start with what you know”: 0.851 L2.Multiply by a conversion factor to get the unit you
want. In this case, 1 L = 1,000 mL3.The unit that you WANT always goes ON TOP of the
conversion factor!0.851 L X 1,000 mL = 851 mL
1 L
More Conversion Practice
Convert 0.765 g to kilograms.1.Always “start with what you know”: 0.765 g2.Multiply by a conversion factor to get the unit you
want. In this case, 1 Kg = 1,000 g3.The unit that you WANT always goes ON TOP of
the conversion factor!0.765 g X 1 Kg = .000765 Kg
1,000 g
More Conversion PracticeConvert 17.3 m to centimeters.
Convert 5.13 m to millimeters.
Derived Units
Derived units: units found by multiplying or dividing the 7 base units.
Examples:Speed is m/s (meters divided by seconds) Area is m2 (length X width)Volume is cm3 (length X width X height)
Properties of MatterMatter has many properties.
These properties can be classified as either physical or chemical…
Properties of Matter
Physical property: A characteristic of a substance that does not involve a chemical change, such as density, color, or hardness.
Examplescolor, state, melting point, boiling point,
density, hardness, etc.
DensityDensity: the ratio of the mass of a substance
to the volume of the substance; often expressed as grams per cubic centimeter (g/cm3) for solids and liquids and as grams per liter (g/L) for gases.
Density = mass volume
The density of a substance is the same no matter what the size of the sample is.
Density is a PHYSICAL property.
Density can be used to identify substances
As I was walking through the parking lot this morning, I found this necklace. I wonder if it’s pure silver? How could I test it to find out?
Chemical PropertiesChemical property: a property of matter that
describes a substance’s ability to participate in chemical reactions.
Examples:Reactivity with oxygenSensitivity to light
Homework
Sec. 1.2 review, pg. 19: #1-11Concept Review: “Describing Matter”(Concept Review packet is due day of Chapter test)
Looking Ahead
Next Time: Section 1.2 Quiz: “Describing
Matter”Lab Write-up
Wednesday:High School Open House
6:30 – 8:00 pm