Quiz #1

Safety, Reaction in a Bag, Heating Baking Soda, Measurements

SAFETY NOTES

For Every Lab:
  • Keep goggles over your eyes until Mr. Leeds says to put them away
  • Report all accidents to Mr. Leeds immediately
  • Use common sense

In Case of Emergency:

  • Nurse extension: 2828

Safety Equipment in Classroom:

  • Fire extinguisher
  • Fire blanket
  • Eye wash/shower

Chemicals:

  • Never taste/touch chemicals
  • Waft liquids to test order, never waft solids or powders
  • Always wash hands with soap and water after lab
  • If chemical touches skin: flush skin with water for 1 minute and tell Mr. Leeds

Glass:

  • Hot and cold glass look the same
  • Never used chipped or broken glass
  • Tell Mr. Leeds and dispose of broken glass in proper trash
  • Never use force to remove or insert glass

Alcohol Burners:

  • Roll up sleeves, put up long hair
  • Never leave a lit burner
  • Never point the open end or a hot test tube at someone or yourself
  • Do not look down into a test tube or beaker while being heated
  • Make sure burner is capped and flame is out when done

End of Experiment:

  • Clean up area and put materials away
  • Make sure burner is out if one was used
  • Keep goggles on until Mr. Leeds says to put them away


REACTION IN A BAG

Purpose: To record the observations that occur when multiple chemical substances are combined and to use my observations to understand the reaction of the chemicals.

Lab Safety:

  • Wear goggles and apron

Experimental Error: Hole or rip in bag

  • Gas could escape
  • You would not know there is a gas being produced

Conclusion:

  • Solid A + Liquid = Hot
  • Solid B + Liquid = Cold
  • Solids A + B + Liquid = Gas

Post-Lab:

  1. Red Liquid- Phenol Red
  • Used as a pH indicator
  • Below 7 turns yellow
  • above 8 turns pink
  • pH indicator- measures acidity, goes from 0-14
  1. Solid A- Calcium Chloride
  • acidic
  • hydrotropic
  • uses- canned veggies, electrolytes in sports drinks
  1. Solid B- sodium bicarbonate (baking soda)
  • alkaline
  • uses- baking, toothpaste, laundry detergent



Scholar Reaction In The Bag Inquiry Demonstration and Lab Activity

HEATING BAKING SODA LAB

PART 1
Purpose: To observe and record what occurs when baking soda is heated.
Lab Safety: Wear goggles and apron
Experimental Errors:
  1. Hole in tubing- won't see gas filling bottle
  2. Stopper not snug- won't see gas filling bottle
  3. Not cleaning rod before beginning- contaminated (part 2)

Post Lab:

  • moisture/condensation at top of test tube comes from hot gas touching cooler top of test tube
  • gas leaving test tube that comes from baking soda and enters inverted bottle

Box Question #1

  • When heated it releases a gas, which allows dough, batter to rise (bread, muffins, cupcakes, etc.)

PART 2

Control Group- Unheated baking soda

Experimental Group- Heated baking soda

Indicator- tea

Variable- A category you try to measure

  • independent variable: causes a change in the depended variable- temp. (heat)
  • dependent variable: color of tea

Control Factors:

  • same type of tea
  • same amount of baking soda
  • same amount of tea
  • same size of test tube


Data (combined, blue dots):

  1. It appeared nothing had happened at the bottom of the test tube
  2. There was water droplets/vapor at the top of the test tube
  3. The water was escaping from the bottle
  4. Gas came from baking soda
  5. Droplets came from hot gas touching cool test tube (top)
  6. Non heated- color of apple juice, a little bit foggy
  7. Heated- looks the same as before
  8. Different, one had the gas removed. Therefore, it is not completely baking soda anymore



Lab 1.1 Heating Baking Soda

VOLUME NOTES

  1. Unit of measurement- cm³ (cubic cm)
  2. Volume= length x width x height
  3. Standard unit of length- meter (M)
  4. 1 centimeter= 0.01 M
  5. 100 cm= 1m
  6. unit cube- small cube, 1cm, on each edge

Volume of Liquids

  1. use a graduated cylinder to measure volume
  2. always check the intervals or scale
  3. units- mL or cm³
  4. 1mL=1cm³
  5. read from bottom of meniscus

Read Box Questions 3-8 for review



SINGLE PAN BALANCE NOTES

  1. Check that pan is clean and dry
  2. Always zero balance before each massing (push all riders to zero/left, and use adjustment knob if needed)
  3. Never switch pans
  4. pick up balance by red bar only
  5. don't zero balance when done

Read box questions 9-13 for review