build a boat… hope it floats - lhs science -...
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Build a Boat… Hope it Floats
Build a boat capable of floating as many
pennies as possible.
Provided a list of materials and their "prices".
Build your boat to meet the time and size
regulations . . .
The Build a Boat Hope it Floats Boat Float-Off
begins 15 minutes from the time I say "Build
Your Boat".
Boats cannot be larger than 4 x 6 x 10
centimeters.
Calculate the total cost of your boat.
The winner of the Boat Float-off is the group
earning the lowest score based on the following
equation:
Score = Total Cost
# of pennies floated
(Boat dimensions cannot exceed 4 cm x 6 cm x 10 cm)
Your whiteboard must include the following: A complete list of materials and the individual costs as well as your
total cost.
Your calculated score = total cost # of pennies
A list of things you discussed when designing the boat.
A list of any obstacles that kept you from building a better boat.
What were your boat's best/worst features?
How many of you could build a better boat now
that you’ve tested yours and seen others
tested?
CHEMISTRY EQUIPMENT
Unit 1: Nature of Science
Branches of Chemistry
Physical Inorganic
Biochemistry
Organic
Analytical
Lab Safety
Hazard Labels
Element symbols to memorize
What is chemistry?
the science that investigates structures and
properties of matter (anything composed of atoms)
Why does water have unique properties?
Why are diamonds so hard?
Why is wax so soft?
How do batteries work?
Why are some elements radioactive?
Properties of Matter
Physical Properties Chemical properties
Can be observed without a chemical change
occurring
Can be observed only when a chemical change
occurs
Ex: That door is brown. The walls are white and
solid. The water coming out of the faucet is a
liquid.
Ex: Paper burns. Plants experience
photosynthesis. An old bike rusts.
Properties of Matter
There are 2 measurable physical properties:
Physical and Chemical Changes
Physical change: atoms are not rearranged
into new substances.
Physical changes include all changes
of state (evaporation, melting, boiling,
sublimation, etc).
Physical and Chemical Changes
Chemical change: bonds are broken
between atoms and new bonds are formed to
make new substances.
“Matter and Change” concept map
Matter and change concept mapAll of the terms below are related in some way so your job is to create a concept map showing their relationship. The arrangement of the terms
is up to you but the branching needs to make sense. For each term you will need to define it in some way- you can start by looking in the book
(pages 34-52) but really try and change them where they make sense to you. You will also need to include a drawing for half of the terms (15)-
the drawing could be an example or something that clarifies the definition. *The starred items will need a minimum of 3 examples each.* When
completed take a picture of your concept map and turn it in on google classroom- make sure entire group names are on there and visible.
Matter Mass
Pure substance Law of conservation of mass
Volume Element*
Intensive property* Compound*
Extensive property* Mixture
Density Homogeneous mixture*
States of matter Heterogeneous mixture*
Solid* Solution
Liquid* Filtration
Gas* Distillation
Physical property* Precipitate
Chemical property* Law of definite proportions
Physical change* Chemical reaction
Chemical change* Reactant
Product
SEPARATION OF MIXTURES
Scientific measurement
Mass: measure of how much matter is in a
substance (g, kg)
Is your mass the
same on the Earth
and moon?
Scientific measurement
Weight: Measure of gravity’s pull on matter
(lbs, oz, N)
Volume: Measure of how much
space is taken up (mL, L)
Scientific measurement
Two types of data:
Quantitative (quantities)
Qualitative (qualities)
Examples of each?
Graphing
Independent vs. Dependent variable?
Scientific Measurement
Scientific measurements need to have a numerical value (in chemistry these will often be very BIG or
very small numbers)
Scientific notation:
Rewrite in scientific notation
1. The population of the world is about 7,117,000,000.
2. The distance from Earth to the Sun is about 92,960,000
miles.
3. The human body contains approximately
60,000,000,000,000 to 90,000,000,000,000 cells.
4. The mass of a particle of dust is 0.000000000753 kg.
5. The length of the shortest wavelength of visible light (violet)
is 0.0000004 meters.
Find a really small or large number that would be better shared in scientific notation.
to do SN on your calculator….
Scientific Measurement
Along with numerical values you always need units (kg, m, cm3, kPa)
Units tell you what property you are measuring
SI units: International System of Units
Scientific Measurements
Measurements also need to be reliable (repeatable)
So when you collect data make measurements with accuracy and precision…
Accuracy: how close a measurement agrees with a true or accepted value.
Precision: how close several trials making the same measurement are to each other.
Accurate or precise?
On formula chart:
Percent Error Calculations
1. Suppose you calculate your semester grade in chemistry to be a 90.1, but you receive a grade of
89.4 on your report card. What is your percent error?
2. On a bathroom scale, a person always weighs 2.5 lbs less than on the scale at the doctor’s
office. What is the percent error of the bathroom scale if the person’s actual weight is 125 lbs?
Reporting Measurements
Significant figure activity
Reporting Measurements
When making measurements report all numbers
that you know with certainty….
And then one digit of uncertainty (estimation)
Reporting Measurements
Measurements need to be reported to the correct number of significant figures
Significant figures: All the numbers in a measurement (including one uncertain one)
On formula chart:
The exceptions:
Don’t worry about sig figs when:
-a number is arrived at by counting (35 people in a room)
-when a number is definition/conversion factor (60 seconds in 1 minute)
How many sig figs?
Measured value:
1. 98
2. .98
3. 980
4. 0.0098
5. 0.009800
6. 98098
7. 980.
8. 1.60 x 108
4. _____
Rounding to correct sig figs
Reporting answers with sig figs
Rules for adding or subtracting:
1. Figure out which number has the least number of decimal places and your
answer can only be to that place
150.0 g H2O
+ 0.507 g NaCl
150.507 g
Reporting Answers with sig figs
Rules for multiplying or dividing:
-Figure out which number in the problem has the least number of sig figs
and that is the number of sig figs that you can have in your answer
(320.5 - 6104.5 / 2.3)
863 x [1255 – (3.45 x 108)]
METRIC
CONVERSIONS
Metric prefix Symbol Relationship Factor
Mega- M 1Mm=1,000,000m 106
Kilo- k 1km=1,000m 103 1000 times larger than base unit
Hector- h 1hm=100m 102 100 times larger than base unit
Deka- da 1dam=10m 101 10 times larger than base unit
base unit (meter, gram) m, g base unit 1
Deci- d 10dm=1m 10-1 10 times smaller than base unit
Centi- c 100cm=1m 10-2 100 times smaller than base unit
Milli- m 1,000mm=1m 10-3 1000 times smaller than base unit
Micro- µ 1,000,000µm=1m 10-6
Nano- n 1,000,000,000nm=1m 10-9
Pico- p 1,000,000,000pm=1m 10-12
Dimensional Analysis
Remember these two ideas: 1. Any number can be multiplied by 1 without changing its value. 2. Multiplying by a conversion factor is like multiplying by 1 because the numerator and the denominator are equal.
In your notebook show your work for the following problems: 1. Convert 23.9 km to m.
2. Convert 4.7 L to mL.
3. Convert 22.8 cm to m.
4. Convert 85 mL to L.
5. Convert 34.89 x 10-6 m to km.
Multi-Step Dimensional Analysis
How many hours are in a fortnight (2 weeks)?
How many inches are there in a football field?
6. Convert your weight in pounds to kilograms if 1 kg= 2.2 lbs.
7. Measure your height in centimeters using the meter stick. Convert your height to kilometers.
8. Measure your arm span in inches. Convert your arm span to centimeters using this conversion factor: 2.54 cm=1 inch.
9. Find the length of a pencil in miles. 1.6 km =1 mi 100 cm =1 m 1,000 m =1 km
10. Find the mass of the paper clip in tons. 2.2 lbs =1 kg 2,000 lbs =1 ton 1kg =1,000g
11. Find the maximum length of time you can hold your breath, in years. 365 days =1 year 24 hours =1 day 60 min =1 hour 60 s =1 min
12. A cheetah can run 72 miles per hour. What is their speed in kilometers per minute.
13. If an object has a density of 15 grams per milliliter, what is it’s density in pounds per gallon.
1 shloom= 7 wibbles 1 gruffle- 60 shlooms6 norleys= 1 fubbyloofer 1 bleep= 12 wibbles1 snorp= 10 norleys 1 bleep= 3 snorps
In a very foreign country, units of time have some very odd sounding names. In the box below, the relationships between units have been given.
Use the conversion factors above to perform the following calculations. Show all of you work!Start with what is given and multiply by the appropriate conversion factor(s). Make sure to include the unit with your answer.1. 2.5 fubbyloofers= _______________ norleys2. 8.0 norleys= _______________bleeps3. 3.4 wibbles= _______________snorps4. 20.3 snorps= _______________fubbyloofers5. 97.2 gruffles= _______________ wibbles6. 5.6 wibbles= _______________fubbyloofers
Density
The measure of how much mass is contained in a given unit of volume.
-It depends on what the composition of the matter is (intensive physical
property), not how much you have.
density of 1g or iron = density of 10g iron
It depends on 2 things:
-how tightly packed the atoms are
-what the atoms are
Density of common materials
The density of water is 1.00 g/cm3.
Objects with a density greater than
1.00 g/cm3 will sink in water.
Objects with a density less than
1.00 g/cm3 will float in water.
Calculating density
On formula chart:
Calculating density
On formula chart:
3. What is the density of a piece of wood that has a mass of 85.4 g and dimensions of 5.67 cm by 2.23 cm by 10.4 cm?
4. A metal cylinder has a diameter of 4.4 cm and a height of 10.5 cm. If the cylinder is silver, which has a densityof 10.5 g/cm3, what is its mass? V = πr2h (Use 3.14 for pi)