IPS Exam Study Guide
By: Jorgi Mandelbaum
Scientific Method
- Identify Problem
- Gather Info
- Form Hypothesis/theory
- Perform Experiment
- Analyze Data
- Conclusion
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 Group - the group that is the 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 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
Volume of Rock
- FInd increment values of cylinder
- fill cylinder w/ an amount of water
- record the volume of water
- put rock into water
- record level of water
- calculate difference b/w two values
Volume of water: 30 mL
Volume of water w/ rock: 33 mL
Volume of rock: 3 mL
1.2 Volume Notes
Volume: L x W x H (A x B x C)
Standard unit of length: meter (m)
1 centimeter (1cm) = 0.01m
^ = 100 100 cm = 1 m
unit cube = 1 cm on each side
Volume of Liquids
-use a graduated cylinder to measure volume **Always check the intervals on scale**
-units = milliliters (mL) or cm3
1 mL = 1 cm3
Safety
Test odors of liquids by wafting them under your nose.
When diluting acid, you must always pour the acid into the water.
You should wash your hands with soap and water after handling all chemicals.
Never use force to remove or insert glass.
Before leaving class, your lab area must be completely cleaned up.
Acid and water mixed together may cause an exothermic reaction.
You must keep your goggles until Mr. Leeds says to remove them.
2828 is the extension for the Nurse in case of an emergency during class.
FALSE You should report all accidents to Mr. Leeds at the end of class.
TRUE You should never throw broken glass into the regular trash.
TRUE If you get any chemcials on your skin you should flush your skin with water and tell Mr. Leeds.
FALSE You can take your goggles off as soon as you finish the lab.
FALSE Hot glass looks different than cold glass.
FALSE It is ok to use a cracked test tube as long as your careful.
FALSE The Emergency Blanket is used if someone really needs to take a nap.
FALSE Water is more dense than acid.
1. List three important safety tips when working with a heating devide (like an alcohol burner).
a. never walk away from a lit burner
b. roll up sleeves
c. put your hair up (not just back)
2. List three safety precautions you should take when using chemicals.
a. do not eat chemicals
b. do not touch chemicals
c. flush skin with water if you come in contact with chemicals.
3. List one thing you should do at the end of every experiment.
a. clean up?
4. List three pieces of safety equipment located within the classroom.
a. fire blanket
b. fire extinguisher
c. eye wash/shower
5. What is the emergency blanket used for?
a. In case of fire, you can wrap yourself in the blanket and it will protect you.
Define exothermic: heat
Chapter 2 Vocab
- Histogram - a bar graph that shows the number of times a value is represented for a large sampling group
- Conservation of Mass - In all changes, mass is exactly conserved, provided nothing is added or allowed to escape. Must be a closed system! Not true for volume
- Laws of Nature - Guessed generalizations based on many experiments. Can be adjusted when necessary to account for any changes in the limitation of a law.
Chapter 3 Vocab
- Characteristic properties- properties that show differences between substances. Examples: density, boiling point, solubility, melting point.
- Density- mass per unit volume of any substance. unity of measure is g/cm3.
3.1
- properties of an object- describes the object itself.
- properties of substance- identify what the object is made of.
Chapter 3 Mass & Volume Notes
- Objects that are made of the same substance that have the same volume, will have the same mass (regardless of their shape)
- The mass am 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
u nits - g/cm3 (grams PER cm3)
Al (Aluminum): 2.7 g/1cm3 = 2.7g/cm3
Labs
Reaction in Bag
Lab 1.1 - Heating Baking Soda
Condensation comes from hot gas touching cooler surface and turning back into a liquid.
Control group - unheated tea and baking soda
Experimental Group - heated tea and baking soda
indicator - tea
Control factors:
- Stirring same time
- same type of tea
- same amount of baking soda
- same amount of tea
- same size test tube
Experimental Errors:
- hole in tubing
- stirring rod contamination
- stopper not on tight
Lab 1.4 - Sand and Water Lab
- sand sticks to the sides of the cylinder (v. of sand and water will be less)
- pours water into sand (v. of sand and water increases)
- pour sand too of fast --> overflow funnel
- sand sticks to funnel (wet)
Does not matter how much sand you begin with, the % of air space is about 40%
Calculations for Sand and Water Lab
- water
-----------
Sand Alone
(waters cancel)
Dry Sand
-Sand alone
--------------
V. of Air
(Sands cancel)
is over of = air over dry sand
Lab 1.8 - Sensitivity of Balance Lab
sensitivity of balance = the margin of error (+/-) when an object is massed
Exp. Errors
- pan mixed up
- cutting uneven
- read balance incorrect
- not zeroing balance
- pencil marks on paper
Part A:
If you mass the same thing over and over. you will not find the same mass but all numbers should be within (+/-) .02 of each other
Lab 2.1 - Dissolving Salt
- consider the sensitivity of balance = every change in mass can be (+/-) 0.02 of each other
- 13 out of 19 show a loss in mass
- 1) Balances all different 2) errors
Errors:
- clean pan b/w mi and mf
- cap not tight --> H2O spills out
- salt spills from pouring the salt in the cap into bottle
- cap not dry
- not shaking long enough
- remove cap before mf
- bottle is wet on the outside during mi
ALL ERRORS LEAD TO A LOSS IN MASS
Histograms
Rule: if data falls on a line, you graph it in the column to the RIGHT
Lab 2.4 - Ice
Exp. Errors:
- not wiping off condensation on outside --> mass increases
- shaking bottle
- ice not fully melted
- not drying bottle and cap --> make mi small and change in mass bigger
- cap not on during mi
- remove cap before mf
Lab 2.5 - Copper and Sulfer
- shaking test tube
- rubber sheet not on tight
- clean pan b/w massing (mi and mf)
- reaction not don't before cap flame
- hole in rubber sheet --> gas escapes
ALL ERRORS LEAD TO A LOSS IN MASS
Lab 2.6 - Alka-Seltzer
- cap is wet
- cap not tight and fast
- water on outside of bottle during mi
- touch tablet after mi
Alka-Seltzer:
- sodium biCARBONate --> baking soda releases gas
- carbon = gas
Lab 3.2 - Cylinders
- re-mass same cylinder
- cylinder is wet when massing (m^)
- not enough H2O to cover cylinder (v down)
- H2O splashes pout of graduated cylinder (v down)
Lab 3.5 - Cubes, Slab, Rock
All have different densities b/c the rock is formed by many substances being compressed together
*different substances = different densities*
Errors:
- mix up cubes
- mass rock after taking volume --> wet = m^, D^
- measure same side of cube/slab twice
- measure from end of ruler, not zero (v down, D^)
Lab 3.6 - Two Liquids
- contaminate cylinders (cylinder is wet)
- dry cylinder AFTER it is massed - M down
- liquid sticks to inside wall of cylinder - m ^, D down
Magnesium sulfate = epson salt
Lab 3.7 - Density of Gas
- hand isnt sealed --> H2O lraks out/gas enters (V down, D ^)
- touch tablet after mi (m^, D^)
- forgot to include foil in mf (m^, D^)
- tubing, tablet, stopper (in this order) (V^, D down)
- condensation on outside test tube for mf (M^, D^)
- hole in tubing/stopper not suggly/taking too long getting tubing in bottle (V down, D^)
Gas comes from sodium bicarbonate
Gas is carbon dioxide (1.8 x 10 -3)