Science Quiz #1

By Matt Kaskel

Lab safety

  • Goggles must be worn over eyes until Mr. Leeds says so
  • Report all accidents to Mr. Leeds immediately
  • Use common sense
  • Nurse extension- 2828
  • Safety equipment
  • 1. Fire extinguisher
  • 2. Fire blanket
  • 3. Eye wash/shower
  • Never taste chemicals
  • You MUST waft only liquids
  • Don't touch chemicals
  • Wash hands after the lab
  • If a chemical touches your skin, flush your skin in water for 1 min
  • Hot and cold glass look the same. So be careful!
  • Don't use broken glass
  • Tell the teacher if there is broken glass and throw it away in the proper trash bin
  • Don't force to remove or insert glass
  • Roll up sleeves and put up hair when dealing with heat
  • Be careful with fire
  • Clean-up after you have finished the lab and turn off your burner


Reaction in a bag

We did this lab to record the observations that occur when multiple chemical substances are combined and to use my observations to understand the reactions of the chemicals.



  • After mixing solid A and solid B and a red liquid, there was a yellow substance that started to foam up. Also, there were some pink spots in the bag. Finally, the bag filled with air.

  • Red liquid- Phenol red
  • Phenol red can be used as a pH indicator which measures the acidity in a substance
  • If the red liquid turns yellow, it means the substance is acidic
  • If the red liquid turns pink, it means that the substance is alkaline
  • Examples- Lemon juice is a 1.5 on the pH scale and Tums are a 10


  • Solid A was Calcium chloride
  • Calcium chloride is an acidic substance
  • It is also hydrotropic. A hydrotropic substance absorbs water
  • It is used in canned veggies to keep them from getting to mushy
  • It is also an electrolyte in sports drinks and it flavors pickles


  • Solid B was sodium bicarbonate (baking soda)
  • not an acid
  • It is used in baking, toothpaste, and laundry detergent



Heating baking soda

We did this lab because we wanted to observe and record the reaction that occurs when baking soda is heated.




Blue dot questions



  • During the lab, nothing is occurring at the bottom of the heated tube.
  • The top of the tube is getting wet and misty (water is dripping into the tube)
  • The water in the bottle is evaporating and turning into a gas
  • The gas comes from the heated baking soda
  • The droplets in the test tube came from the gas from the baking soda rising and leaving the heat source and then turning into a liquid.
  • When we put the tea into the heated beaker, it turned really dark and dense. When we put the tea into a normal beaker, the tea became very diluted.
  • The two white powers are different because the unheated is only baking soda and tea, so the heated should be the same color




Heating baking soda lab terms


  • control group- unheated baking soda and tea
  • experimental group- heated baking soda and tea
  • indicator- tea (showed that the substance in the heated test tube was not baking soda
  • Variable: a category that you try to measure
  • Independent variable: it causes a change in the dependent variable- The heat
  • Dependent variable: the tea


About the substance

Baking soda can be used in baking because when it is heated, it releases a gas. It helps the batter rise. Example: bread, cookies, and cupcakes.


Heating baking soda pre lab

Volume

  • the unit of measurement for volume is in cm3 (cubic centimeters)
  • Volume formula- LxWxH
  • Standard unit of length- Meters (M)
  • 1 cm = .01m
  • 100cm= 1m
  • a small unit cube has 1cm on each edge


Volume of liquids

  • use a graduated cylinder to measure the volume
  • always check the intervals on a scale when measuring
  • 1mL=1cm3


Single pan balance notes

  • check that pan is clean and dry
  • always "zero" balance before each massing
  • push all riders to zero (left)
  • use adjustment knob if needed
  • DO NOT switch pan
  • pick up the balance by red bar only
  • Don't zero the balance when done