1.1-1.4 Study Guide
1st IPS quiz
Lab Safety
- Always wear goggles over your eyes until Mr. Leeds says to put them away.
- Report all accidents/spills to Mr. Leeds immediately
- Use common sense
Nurse:
- ext. 2828
Safety Equipment:
- Fire extinguisher
- Fire blanket
- Eye wash/shower
Chemicals:
- Never taste chemicals
- Waft to detect odor
- Never waft solids or powders
- Avoid touching chemicals
- Wash hands with soap and water after lab
- Flush skin with water for 1 minute and notify Mr. Leeds if chemicals touch your skin
Glass:
- Hot glass and cold glass look the same
- Never use chipped or broken glass
- Tell Mr. Leeds and dispose of broken glass in the proper trash can
- Never use force to remove or insert glass
Alcohol Burners:
- Roll up sleeves
- Put up long hair
- Never walk away from a lit burner
- Never point 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 capped and flame is out when done
End of Experiment:
- Clean up area and materials completely! (or you lose points)
- Make sure the burner is out if used
- Keep goggles on (over eyes) until Mr. Leeds says to put them away
Reaction in a Bag Lab
Multiple chemical substances are combined and they cause many chemical reactions.
- When Calcium Chloride is combined with a liquid, it produces an exothermic reaction (heat)
- When Sodium Bicarbonate is combined with a liquid, it produces an endothermic reaction (cold)
- When Calcium Chloride, Sodium Bicarbonate, and a liquid are combined, they produce a gas
- Calcium Chloride combined with Phenol Red creates an orange color
- Sodium Bicarbonate combined with Phenol Red creates a pink color
- Calcium Chloride causes Sodium Bicarbonate to dissolve
Substances:
Phenol Red
- Used as a ph indicator
- below 7 turns yellow
- above 8 turns pink
Calcium Chloride
- Calcium and Chloride
- Acidic
- Hydrotropic (attracted to/absorbs water)
- Keeps canned veggies from getting mushy, is an electrolyte in sports drinks, flavors pickles
Sodium Bicarbonate
- Baking soda
- Not acidic
- Used in baking, laundry detergent, and toothpaste
Heating Baking Soda Lab
Record the reaction that occurs when baking soda is heated
Science:
Where did the condensation at the top of the test tube come from?
- Baking soda releases gas, which rises up through the test tube and tubing into the bottle
- The hot gas touches the cooler surface at the top of the glass test tube
- The gas turns back into liquid
- The liquid is condensation
Is heated baking soda the same as unheated baking soda?
- No, they are different substances
- After the two baking sodas were each mixed with tea, the color of the tea in the two test tubes was different
- Since the colors were different, something must be different in one of the tubes (heated)
Control group: Unheated test tube
Experimental group: Heated test tube
Indicator: Tea (shows that heated baking soda has changed)
Variable: Something that you try to measure
- Independent variable causes a change in the dependent variable
- Independent Variable: Temperature (heat)
- Dependent Variable: Color of tea
Control Factors: (factors we control during the experiment)
- Same type of tea
- Same amount of baking soda
- Same amount of tea
- Same stirring time
- Same size test tube
Experimental Errors:
- Tiny hole in tubing (won't see the bottle fill with gas)
- Stopper is not snug (won't see the bottle fill with gas)
- Stirring rod not clean before you begin (contamination)
Extra Question:
- The amount of condensation that forms at the top of the heated test tube is less or equal to the amount of baking soda being heated because the condensation comes from the baking soda, which cannot produce more than itself
Volume
- Unit of measurement: cm3 (cubic centimeters)
- Volume = l x w x h (a x b x c)
- Standard unit of length = meter (m)
- 1 centimeter = .01 meter
- 100 centimeters = 1 meter
Liquids:
- Use a graduated cylinder to measure volume
- Always check the intervals or scale
- Units = millimeters (mL) or cm3
- read from bottom of meniscus
Single Pan Balance
2. Always "zero" balance before each massing
- Push all riders to zero (left)
- Use adjustment knob if needed
3. Never switch pans
Box Questions
3. 50 cm3
4. Box A has a greater height or width than box B.
5. The stone has a volume of 7 cm3.
6a. 8 cubes will be needed to build a cube with 2 cm edges.
6b. 27 cubes will be needed to build a cube with 3 cm edges.
6c. Cube A has a volume of 8 cm3. Cube B has a volume of 27 cm3.
7. The 2nd box has the larger volume.
8. The divisions are not equally spaced because the cone is narrower at the bottom than the top. As the surface increases, the depth decreases.
9a. Arrow 1 is at 1.2 cm, and arrow 2 is at 3.8 cm. No, you can't.
9b. Arrow 3 is at 1.62, Arrow 4 is at 2.51, and Arrow 5 is at 4.50. No, you can't.
9c. The positions of the arrows shouldn't be measured to the 0.1 because the arrows aren;t exactly on the millimeter lines.
10a. 0.1 of a cubic centimeter
10b. 0.2 of a cubic centimeter
11a. 4.0 cm3
11b. 1.25 cm3
12. The more information you have about a number, the better. Otherwise, the number may be estimated differently. 12 may be the rounded version of 12.1, and 12.0 may be the rounded version of 12.0
13. If graduated cylinders are taller and narrower, more marks or divisions can fit.