Exam Study Guide
IPS period 6 By Andie Weinberg
CHEMICALS
SAFETY EQUIPMENT IN THE CLASS ROOM
AT THE END OF THE EXPERIMENT CLEAN UP YOUR AREA AND MATERIALS COMPLETELY!!
GLASS
Alcohol Burners
Purpose of the reaction in a bag lab
HOT TEMPERATURE
COLD TEMPERATURE
GAS
Phenol Red
- used as a pH indicator
- below 7 turns yellow
- above 8 turns pink
Calcium Chloride
- mildly acidic
- hydro tropic (attracted to and absorbs water)
- canned veggies
- electrolyte in sports drinks
- flavored pickles (salty)
Sodium Bicarbonate
- baking soda
- not acidic
- baking
- cat litter
- toothpaste
- laundry detergent
pH scale
- Measures acidity
- goes from 0-14
- 0-- is acidic
- 7-- is neutral
- --14 is alkaline
- lemon juice 1.5
- tums 10
PURPOSE FOR 1.1 LAB
Why do you think baking soda is used in baking?
Box Questions:
4. Box A must have a greater width or height if the length of box A is less than B.
5. The volume of the stone is 7 cubic centimeters if the water was at 25.0 centimeters cubed then it went to 32.0 centimeters cubed.
6a. 8 cubes are needed to build a cube that measures 2 cm along each edge.
6b. 27 cubes are needed to build a cube that measures 3 cm along each edge.
6c. 8 cubic centimeters and 27 cubic centimeters is the volume of each of the cubes.
7. Box B (25 cm long, 16 cm wide, and 15 cm deep) is bigger than box A (30 cm long, 15 cm wide, and 10 cm deep).
8. The marks on the cone-shaped cylinder are not equally spaced because the more you go up the larger the width becomes.
9a. Line I is 1.3 centimeters, and line II is 3.8 centimeters.
9b. Line III is 1.65 centimeters, live IV is 2.51 centimeters, and live V is 4.50 centimeters. You cannot estimate their positions to the 0.0001 centimeter because it would be inaccurate.
9c. There are tick marks to show us a more exact answer.
10. On cylinder A each tick mark represents 0.1 and on cylinder B each tick mark represents 0.2.
11. The level of liquid in Figure A is 4.0, and Figure B is 1.30.
12. They could have rounded from 11.5-12.4 for the first one, 11.95-12.04 for the second one, and 11.995-12.004 for the third one.
13. The advantage to making graduated cylinders narrow and tall rather than short and wide is that it is easier to read. The lines are further apart because there is less surface and more depth.
What do you observe at the bottom of the test tube?
What do you observe near the top of the test tube?
What do you observe in the inverted bottle?
Control group in 1.1 lab was the unheated test tube.
EXPERIMENTAL GROUP IN 1.1 LAB WAS THE HEATED TEST TUBE.
THE INDICATOR IN 1.1 LAB WAS THE TEA.
LAB 1.1: independant variable: the temperature (in this case heat)
LAB 1.1: DEPENDENT VARIABLE: COLOR OF TEA.
VOLUME
BALANCE
Standard unit of length is the meter.
Unit of weight is the gram.
Test 1
In a rectangular box of the following measurements were found: six cubes fit exactly along one edge, and five cubes fit exactly along another edge. However, after seven horizontal layers had been stacked in the box, a space at the top was left unfilled.
A: 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?
A: 224.1 cubes
To stay physically fit, Mr. Leeds is constantly training (and injuring himself). He weighs a trim 178 lbs. What is his weight in kilograms?
Did any of the students make a mistake in their massing?
During the Heating bakind soda experiment a lab group does not realize that they have a hole in their rubber tubing. How will this affect their understanding of the lab?
Here are the ingredients in mr. Leeds famous pumpkin bread. Next to each ingredient identify which are measured by mass, volume, or other means.
1 tablespoon baking powder- volume
1 1 pound can of pumpkin- mass
1/2 teaspoon vanilla- volume
cinnamon to taste- other
1/2 cup milk- volume
Auditorium- Count; Saucepan- Volume; Bridge- Mass; water tank- Volume
Sand lab experimental errors:
- pour water into sand (water sits on top of sand because the air spaces dont allow the water to filter down)
Why were lab groups instructed to use different amounts of sand? (what was the purpose?)
Sand Lab box questions #14-17
MASS NOTES
Beqa
standard unit
conversions
1kg= 2.2 lbs
Box questions #18-22
Sensitivity of a Balance Lab
Part A chart
mass of stopper (g)- 7.729
#2 mass of penny (g)- 3.080
mass of stopper (g)- 7.720
#3 mass of penny (g)- 3.071
mass of stopper (g)- 7.671
#4 mass of penny (g)- 3.066
mass of stopper (g)- 7.669
Part B
Mass of 20 x 20
0.590
Mass of single square
0.001475
Mass of 4 squares
0.0059
Initial mass of stopper: 17.250 grams
# of group
D Mass (Yes or No)
Mass (g)
1
No
17.250
2
Yes
17.279
3
No
17.279
4
Yes
17.300
5
No
17.300
6
Yes
17.320
7
No
17.320
8
Yes
17.331
9
No
17.331
10
yes
17.339
Sensitivity of the balance
D Mass
0.089
Number of yes’s
5
Sensitivity
0.0178
sensitivity calculations
- ending mass (#10)- initial mass of stopper= delta mass
box questions #26
A: by adding them and dividing by 3.
CHAPTER 2
2.1 Purpose
Experimental errors
- outside of bottle is not wet during the mi
- not drying off the cap --> water in mi not mf
- spill salt when pouring into bottle
Histograms
Rules
rule- if data falls on a line it is graphed in the column to the right
2.4 The ice, ice baby lab
Purpose
formulas
bot/cap/water-bot/cap= mf of water
mf-mi= delta mass
condensation and errors
**need change in temperature**
Experimental errors
Error 1
Error 2
Error 3
2.5 The mass of copper and sulfur purpose
2.5 Post-lab
-melting point of sulfur 112 degrees Celsius
-yellow smoke --> water in sulfur turns to vapor (gas) and rises in the test-tube
- when it cools --> sulfur bonds with copper and forms copper sulphide
experimental errors
- hole in the rubber sheet or sheet is not on tightly--> gas can escape (lose)
- clean pan between mi and mf
2.6 the mass of a Gas
Purpose
Errors
- cap is wet during mi- lose mass
-water in the pan during mi- lose mass
- if cap not on tight or not on quick enough- lose mass
Alka-Seltzer
-Aspirin, citric acid, sodium bicarbonate
**sodium bicarbonate- produces a gas when heated and mixed with water
Conservation of Mass Notes
Closed system
No delta Mass (considering sensativity)
Lab 2.4- 55%
Lab 2.5- 50%
Lab 2.6- 47%
The Law of Conservation of Mass
Chapter 3
Characteristic properties
property of a substance- this helps you to identify what the object is made out of
3.2 Mass and Volume Lab
Errors
- cylinder is wet when massed- mass increase
- dropping cylinder in, water splashes out- volume down