EXAM STUDY GUIDE
Taylor Jane McKee
IPS Lab Safety Notes
- goggles must be kept OVER YOUR EYES until Mr. Leeds says to put them away **even if you are already finished and cleaned up**
- report ALL accidents/spills to Mr. Leeds immediately
- try your best to use common sense
In Case of Emergency
- Nurse: ext: 2828
Safety equipment in classroom
- fire extinguisher
- fire blanket
- eye wash/shower
- never taste chemicals
- Always WAFT liquids to detect odor
- NEVER WAFT SOLIDS/POWDERS!
- avoid touching chemicals
- always wash hands with soap and water after lab
- if chemicals touch skin: flush skin with water for 1 minute AND notify Mr. Leeds
- hot glass and cold glass look the same
- never use chipped or broken glass -tell Mr. Leeds and dispose of broken glass in proper trash
- never use force to remove or insert glass
- roll up sleeves, put UP long hair, NOT just pull back (or you cannot do lab)
- 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
- make sure burner is sapped and flame is out when done
End of Experiment
- CLEAN-UP AREA & MATERIALS COMPLETELY!!!! (Or you LOSE points)
- make certain that burner is out of one was used
- keep goggles on (over eyes) until Mr. Leeds says to put them away
standard unit of length=meter (m)
1 centimeter (1cm)= 0.01m
Volume of Liquids
-use a graduated cylinder to measure volume
*Always check the intervals or scale
units= mil liters (mL) OR cm3
-read from bottom of meniscus
Lab: React in a Bag
B + liquid = cold (Endothermic Reaction= takes it away)
A + B + liquid = gas
Red Liquid or Phenol Red
- used as a pH indicator
- below 7 turns yellow
- above 8 turns pink
- calcium chloride (calcium + chlorine)
- hydrotropic: attracted to water (absorbs water)
- canned vegetables (keeps them from getting mushy)
- electrolyte in sport drinks
- flavored pickles
- sodium bicarbonate (baking soda)
- hot acidic
- cat litter
- laundry detergent
Lab: Heating Baking Soda
control group: unheated test tube
experimental group: heated test tube
indicator: tea (showed you that that heated test tube wasn't baking soda)
variables: something you want to measure
independent variable: causes a change in the dependent variable
dependent variable: color of the tea
- same type of tea
- same amount of baking soda
- same amount of tea
- same stirring time
- same size test tube
It releases gas when heated, which helps dough/batter to rise.
3. How many cubic centimeters of water are required to fill a graduated cylinder to the 500.0-mL mark?
4. rectangular box A has a greater volume than rectangular box B but the length of box A is less than the length of box B. How is this possible?
Box A has more space then box B.
5. Adding a stone to a graduated cylinder containing 25.0 cm3 of water raises the water level in the cylinder to the 32.0 cm3 mark. What is the volume of the stone?
6. a. how many 1 cm cubes will be needed to build a cube that measures 2 cm along each edge?
b. How many 1 cm cubes will be needed to build a cube that measures 3 cm along each edge?
c. what is te volume, in cubic centimeters, of each of the cubes in a and b?
8 cm3 + 27 cm3
7. One rectangular box is 30 cm long, 15 cm wind, and 10 cm deep. A second rectangular box is 25 cm long, 16 cm wide and 15 cm deep. Which box has the larger volume?
The second rectangular box
8. figure A shoes a cone-sharped graduate used for measuring the volume of liquids. Why are the divisions not equally spaced?
As the surface increases the depth decreases
If the height of the space was half the length of an edge of a unit cube, what was the volume of the box?
6x5x7.5= 225 cubes
If the height of the space was 0.47 of the length of an edge of a unit cube, what was the volume of the box?
6x5x7.47= 224.1 cm3
What is the mass of an iron bar that is 2cm x 4cm x 11cm? (1cm3 of iron has a mass of 7.8)
1cm3/88cm3=7.8/x x= 686.4g you get 88 by 2 x 4 x 11
Part B: Lab Experiments:
1. During the Heating Baking Expiration a lab group does not realize that they have a hole in their rubber tubing. How will this affect their understanding of the lab?
thye do not know that baking soda produces a gas when heated.
2. During the Reaction in a lab group does not realize that there is a hole in the zip lock bag. How will this affect their understanding of the lab?
not know how the reaction produces a gas.
3. For the Measuring Volume by Displacement of Water Experiment Mr. Leeds assigned lab groups differetn amounts of dry sand to being the lab. Why did he do this?
A group gets approz 40% air space no matter what they start with.
4. In the sensitivity of a balance lab you were instructed to add 10 groups of squares with a mass between .003g and .007g to an already massed stopper. Why did they choose this range of mass for your 10 groups of squares and not a smaller range; for example: .001g and .003? How would this have change your lab?
The mass would be too small for balance to defect. There would be no change in mass.
Test # 2
- start the lab over
2. In all four experiments from Chapter 2 the common theme involved investigating changes in mass of different states of matter. You now know that in all the labs there should be no change in mass because:
- Law on conservation of mass
3. You are working in a lcass with no air conditioning, it is 90 degrees F. Your lab is to take the mass of water (that is 65 degrees C) in a small plastic bottle with a cap on, then place the bottle in a walk-in freezer allowing the liquid to solidify, then re-mass the bottle while in the greezer. What is a possible error you should be aware of:
-condensation may form on the inside of the bottle during the Mi and then freeze
4. A lab group dissolves 2g of salt into 8cm3 of water in a beaker with no cover. After a few days all of the water has evaporated. What will remain in their beaker?
- 2g of salt
-it is the most accurate method
- we did not have to transfer liquid
3. During the Density of a Gas lab thee rubber tubing is incorrectly inserted near the bottom of the bottle. This will cause...
- less gas to collect in the bottle
4. If the error in #3 is made it will have the following affect:
-volume decrease, density increase
5. When calculating the density of a rock (irregular shape) it would be an experimental error to...
- find the volume prior to massing
6. When the alka seltzer is mixed with water, sodium bicarbonate within the tablet resales:
- carbon dioxide
7. In the Density of a Gas lab a student forgets to include the foil for the Mf, the result is:
- mass of gas increases, density increases
8. Epsom salt is the marketing name for which chemical compound: