IPS Exam Study Guide
Scientific Method Notes
- Identify problem
- Gather info
- Form hypothesis/ theory
- Perform experiment
- Analyze data
- Conclusion
Lab: Reaction in a bag
- Solid A, Solid B, Red liquid gets produced, cold and hot, turns yellow
- Solid A and a Liquid B gets hot
- Solid B and a liquid gets cold
Solid A and Solid B with a Liquid will produce a gas
to Have the Liquid turn yellow you need Solid A, Solid B, and Red liquid
CHAPTER 1
Vocabulary
- observation- information obtained by the senses- often by direct measurement
- Inference- a conclusion based upon known observations
- Hypothesis- a proposed solution to a scientific problem
- Control factors- the variables that are held constant. They are the same for both the control group and the experimental group
- Control group- the group that is the standard for comparison in any experiment
- Experimental group- the group receiving the variable being tested
- 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 determine the volume of a solid or gas
- Mass- the amount of matter in a substance (true of solids, liquids, and gases)
- Meniscus- the curved portion of a liquid when in a container. Must read the bottom of the meniscus at eye level for proper measurement.
Lab: Baking Soda
- water started to lower
- test tube burnt
- condensation caused for there to be droplets in the test tube
Errors
- Hole in rubber tubing
- topper is not on tight
- tubing is not at top fo bottle
- cap burner before removing tubing
Post Lab
- gas comes from the baking soda because if you heat a test tube without baking soda, the gas does not form
- when warm gas touches coller surfaces it turns back to a liquid
- you know that the un-heated test tube is baking soda and tea
- if the color is different, then the heated baking soda must have changed
- Control Group: un-heated baking soda and tea
- Experimental group: heated baking soda and tea
- Indicator: tea
- Control factor: amount of baking soda, amount of tea, same type of tea, amount of stirring time
1.2 Volume notes
Volume: L*W*H (axbxc)
Standard unit of length- Meter (M)
Centimeter (1cm)=.01M
100
100cm=1M
Volume of liquids
- use a graduated cylinder to measure volume
- ***Always check the intervals or scale
- units=Milliliters (ML) or cm3
- 1ML=1cm3\
Single Pan Notes
- check that pan is clean and dry
- always "zero" balance before EACH massing
- push all riders to zero
- adjustment knob if needed
- NEVER switch pans
- pick up balance by red bar only
- return riders to zero when done
Lab: Volume of Sand
- Sand and water- water= sand alone
- dry sand- sand alone= air space
- is/of
Errors
- sand sticks to the side of wet cylinder= volume of snad and water will be lower
- if you record sand level NOT water level
- pour water into sand= volume of sand and water will go up
- sand gets stuck in funnel if its wet
- pour sand too fast= overflows funnel
Extra question
- Why were lab groups instructed to use different amounts of sand?
- did not matter how much sand you began with, the % of air space within the sand was all around 40%
Lab: Sensitivity of Balance
- Change is in mass/ number of yes's= sensitivity of the balance
- Mf- Mi= Change in mass
Post Lab
Pennies
- Before 1982: 95% copper 5% zinc
- After 1982: 2.5% copper 97.5% zinc
- in 1943 were zinc plated steel
Sensitivity of balance
- The margin of error (+-) your balance has when massing an object
CHAPTER 2
Lab: 2.1
- Mi= Initial Mass
- Mf= Final mass
Post Lab
- Consider the sensitivity of balance- every change in mass could be +- 0.02 of the amount given
- 14 out of 18 show a decrease in Mass
Errors
- cleaning pan between Mi and Mf
- salt spills from cap to bottle
- remove cap before Mf
- not shaking long enough
- cap is not tight- water spills out
- not drying cap- starts dissolving
- bottle is wet outside for Mi
Most lead to a decrease in Mass
Lab: Mass of Ice and Water
- Condensation- comes from warm water vapor touching the cooler surface of bottle. It changes from gas to liquid
- Water vapor- much warmer than surface of the bottle
Errors
- not wiping off condensation on outside
- ice is not melted finally
- shaking bottle
- not drying before massing
- removing mass before mass final
Lab: Copper and Sulfur
- shake test tube- sulfur is stuck to sides
- hole in the sheet
- sheet is not tight enough
Lab: Mass of a Gas
- That effect the change in mass
- cap not on tightly
- not drying outside bottle before Mi
- inside cap not dry
- That effect the Mi
- removing cap
- water splashes out when loosening cap
gas is hard to work with because you cannot see it and its hard to contain
Law of Conservation of Mass Notes
- Mass of gas lab- 19 out of 30
- copper sulfur- 6 out of 10
- ice lab- 8 out of 20
- salt lab- 3 out of 18
In a closed system Mass will remain constant, regardless of the action of the processs inside the closed system.
Mass is always conserved, however, in a nuclear reaction sam 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
CHAPTER 3
Vocabulary
- Characteristic Properties- properties that show differences between substances Ex: density, boiling point, solubility, melting point
- Density- mass per unit of any substance. Unit of measure is g/cm3
- Property of object- describes the object itself
- identify what the object is made of.
3.2
- re-mass same cylinder
- cylinder is wet when massed
- not enough water in graduated cylinder
- water splashes out of graduated cylinder
Mass and volume notes
- objects that are made of the same substance that have the same volume, will have the same mass
- the mass of an object will double if its volume doubles
- objects that have the same volume but are made of different substances will NOT have the same mass.
3.3: Density
- M/V= D
- Units: g/cm3 (grams per cm3)
- Al: 2.7/1= 2.1g/cm3
Function graphs
3.5: Density of solids
- all have different densities because the rock is formed by many substances being compressed together
- Different substances= different densities
Errors
- measure volume of rock before massing- mass goes up, density goes up
- mix up the cubes
- measure same side of cube/ slab twice
- measure from end of ruler- not zero: volume goes down- density goes down
3.6: Density of Liquids
Errors
- cylinder is contaminated
- cylinder is wet when massed
- dry out the cylinder after its massed
- same liquid sticks to inside wall: volume decreases, density increases
Liquids had something dissolved into it
- water with magnesium sulfate- epson salt
Lab: 3.7
- hand not tight on bottle: water leaks out- volume goes up, density goes down
- spill water when finding volume in bottle
- touch tablet after Mi- mass goes up, density goes up
- hole in tubing/ too slow putting tubing in bottle/ stopper not tight- volume goes down, density goes up
- air bubble in bottle- volume goes up, density goes down