IPS EXAM STUDY GUIDE
By: Hannah Weinstein
Lab Safety
FOR EVERY LAB:
Goggles must be kept ON YOUR FACE until Mr. Leeds says to put them away.
Report ALL accidents/ spills to Mr. Leeds immediately
IN CASE OF EMERGENCY:
2828
SAFETY EQUIPMENT IN CLASSROOM:
Fire extinguisher
Fire blanket
Eye wash/shower
CHEMICALS:
Never taste chemicals
Always WAFT liquids to detect odor
Never WAFT solids/ powders
Avoid touching chemicals
Always wash hands with soap and water after the lab
FLUSH SKIN WITH WATER IF OCNTACT WITH CHEMICALS OCCURS AND NOTIFY MR.LEEDS
GLASS:
Hot glass and cold glass look the same
Never use chipped or broken glass
Never use force to remove or insert glass
ALCOCHOL BURNERS:
Roll up sleeves, put UP long hair, Not just pull back
Never Walk away from a lit burner
Never point the open end of a hot test tube at yourself or someone else
Do not look down into a test tube/beaker while it is being heated
DILUTING ACID:
Acid must be added to water
Never add water to acid.
Could cause and exothermic reaction
Water is less dense (lighter) than acid so it will sit on top of acid and could splash out
END OF EXPERIMENT:
Make sure burner is capped and flame is out
Clean up area and materials completely
Laws of Conservation of Mass
In a closed sysstem mass will remain constant regardless of the actions of the processes inside the closed sytem.
Mass is always conserved, however in a nuclear reaction some mass is lost. The energy released in a nuclear reaction will be absorbed into surrounding material, adding mass to it. So, the mass is not really "lost".
Mass and Volume Notes
Objects that are made of the same substance that have the same volume will have the same mass (regardless of shape)
The mass of an object will double if its mass doubles.
Objects that have the same volume, but are made of different substances will not have the same mass.
Vocab
CHAPTER 1 VOCABULARY:
Observation: infromation obtained by the senses-often by direct measurement
Inference: a conclusion based upon known observations
Hypothesis: a proposed solution to a scientific problem
Control Group: the group that is standard for comparison in any experiment
Experimental Group: the group receiving the variable being tested
Control Factors: the variables that are held constant. They are the same for both the control group and the experimental group
Indicator: a substance used to show the presence of another substance.
Volume: the amount of space something occupies. True of solids, liquids, and gases.
Volume Displacement Technique: quick and easy way to determing the volume of a solid or gas.
Mass: the amount of matter in a substance (true of solids, liquids, and gasses)
Meniscus: the curved portion of a liquid when in a container. Must read the bottom of the meniscus at eye level- for proper measurement.
CHAPTER 2 VOCABULARY:
Histogram: a bar graph that shows the number of times a value is represented for a large simplifying group.
Conservation of Mass: In all changes, mass is exactly conserved, provided nothing is added or allowed ro escape. Must be a closed system. Not true for a volume.
Laws of Nature: Guessed generlizations based on many experiments. Can be adjusted when necessary to account for any changes in limitizations of a law.
CHAPTER 3 VOCABULARY:
Characteristic Properties: Properties that show differences between substances. Examples: density, boiling point, solubility, melting point.
Plateau: The flat portion of a graph. Indicates no change in the dependant variable. (y axis)
Phase Diagram: A graph that shows the changes in state of matter for any substance. Represents physically challenge in the substance.
Scientific Method
1. Identify a problem
2. Gather info
3. Form hypothesis/ theory
4. Perform experiment
5. Analyze data
6. Conclusion
Chapter 1: Reaction in a Bag
Chapter 1.1: Baking Soda Lab
Blue Dot Questions:
1. Where does the gas come from? The gas comes from the baking soda because when you heat an empty test tube, there is no gas.
2. If the color changes and is diferent that the heated bking soda, did it change? Yes
3. How many cubic centimeters of water are required to fill a graduated cylinder to the 50. ml mark? 50 cubic centimeters
4. A student has a number of cubes that measure 1cm along an edge. How many cubes will be needed to build a cube that measures 2cm along an edge. (there are 6sides) 8cm3
POST LAB:
(look at diagram)
Baking Soda - Sodium Bicarbonate
Control Group - unheated baking soda and tea
Experimental Group - heated baking soda and tea
indicator - tea
control factors - amount of baking soda we used
amt of tea
some type of tea
Experimental Errors:
a whole in the rubber tubing
stopper is not on tight
cap burner before removing tube
EXTRA EXTRA READ ALL ABOUT IT!
Standard Unit of Length: Meter (m)
1 centimeter: .01 m
100 cm: 1m
1ml : 1cm3
1kg: 2.2 pounds
1kg: 1,000 g
ALL SCIENCE USES THE METRIC SYSTEM!!!!!
1.3 THIS IS NOT A LAB THIS IS MEASURING RULERS AND CYLINDERS
SEE PAGE 4 OF NOTES FOR BOX QUESTIONS
Single Pan Balance Notes:
Check that pan is clean and dry
Always "zero" balance before EACH massing
Push all riders to zero (left)
Use adjustment knob if needed
NEVER switch pans
Pick up by red bar only
Return riders to zero when done
1.4 Measuring Volume by Displacement of Water Lab
See Chart of V. of Dry Sand etc.
EQ:
Why were lab groups instructed to use different amounts of sand?
The purpose was to show that if we all are assigned different amounts and we are not precise with our answers, the numbers can be completely different.
Does it matter how much sand you began with no matter how many lab groups? No, the number of sand all was around 40%.
How would you fing the weight of a cork stopper? Attach a weight with a known volume to the cork, and weigh it down. After, subtract the volume of the weight and water when done.
1.8 The Sensitivity of a Balance
SEE MR. LEEDS FOR HELP ON THIS CHART!
Change in Mass over the number of yes's equals the sensitivity.
How would you find the volume of a sponge? L W H
What are you actually finding?volume of the air space and sponge
Chapter 2.1 The Mass of Disolved Salt
I conclude that as the salt disolves, the balances mass will begin to change, and will weigh less.
Experimental Errors:
Salt spills from cap to bottle
remove cap before mf. something could spill out
not shaking long enough
cap is not on tight enough H20 spills out
not drying cap, starts dissolving
if outside bottle is wet during Mi.
BQ:
Do you need to have the mass of the water by itself and the salt by itself? No, you only need to know the mass before and after.
2.4 Mass of Ice and Water
See Chart (one of the blue marked pages)
2.5 The Mass of Copper and Sulfur
See Chart (page after blue mark)
Experimental Errors:
If there is a hole in the rubber sheet
if you shake the test tube and sulfur gets stuck to the side
Sheet not on tightly
BQs:
13.) What is the apparant percentage change in mass of the reacting substance?
change in mass over mi equals x over 100.
14.) see directions above. (pg.37) Do you think it reasonable that mass remained the same- yes because the change in mass is within the sensitivity of the balance.
2.6 Mass of a Gas
See Chart
Experimental Errors:
If the bottle is wet on the outside then there will be extra mass.
Cap not on tightly
Not drying outside of bottle before Mi
Inside cap is not dry
BQs:
There is a law, what comes up must come down is this true and does this aply to the conservation of mass? Yes, it follow the laws of gravity. You must be withing a gravitational pull though.
On a sunny day the sky is blue. Is this a law of nature? Why or why not? Yes, if there is no are pollution, smog, the sky is blue.
Look a bq the last question on pg 40.
ASK Mr. Leeds MAJOR QUESTION ABOUT MASS OF THE GAS!! half page folded
Chapter 3.1 Propery of a Substance and an Object (not real lab)
Property of an object: describes the object itself
Property of a substance: Identify what the object is made out of
3.2 Mass and Volume
Experimental Errors:
Re mass the same cylinder
Cylinder is wet when massed
Not enough h2o is graduated cylinder
H2o splashes out of graduated cylinder
3.3 Density
DENSITY IS A SUBSTANCE!
m/V=d
G/CM3
different substance=different densities
Experimental Errors:
Mix up cubes
Measure same side of cube/slab twice
measure end of ruler not zero
measure volume of rock befoer massing
3.6 The Density of Liquids
See Chart
Experimental Errors:
Cylinder contaminated
liquid sticks to inside wall of cylinder
dry out cylinder after massed
Magnesium Sulfate - Epsom Salt
3.7 The Density of a Gas
See Chart
To find the density - Mass of Gass/ Volume of Gas which is (change is mass/ change in volume)
Experimental Errors:
Some water could leak out of the bottle
Spill some water when finding volume in bottle.
If you touch the tablet after the Mi
Hole in the tubing
Air bubble in bottle
Foil left behind.
Gass is Carbon Dioxide
REVIEW PAGE 51 !!!! :D