Quiz #1 Study Guide

Sydney Lubetkin

Safety Quiz Notes

Nurse's extension number:

  • 2828

Safety equipment in the classroom:

  • Fire Extinguisher
  • Fire blanket
  • Eye wash/station

Chemicals:

  • Never taste chemicals even if they look yummy
  • 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

Glass:

  • Hot glass and cold glass look the same
  • Never use chipped or broken glass
  • Never use force to insert or remove glass


Alcohol Burners:

  • Roll up sleeves, put up long hair
  • 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 capped and flame is out when done


End of Experiment:

  • Clean up area and materials completely (or you lose points)
  • Make certain that burner is out if one was used
  • Keep goggles on (over eyes) until Mr. Leeds says to put them away



Reaction in a Bag Lab

Red Liquid:


  • phenol red
  • used as a pH indicator
  • below 7 turns yellow
  • above 8 turns pink


Two Solids:

A:

  • Calcium Chloride (calcium + chloride)
  • acidic
  • hydrotropic: absorbs water (attracted to water)
  • Uses: canned veggies(keeps from getting mushy). electrolytes in sports drinks, and flavors pickles (salty flavor)


B:

  • sodium bicarbonate (baking soda)
  • not acidic
  • uses: baking, toothpaste, laundry detergent


pH scale:

  • measures acidity
  • goes from 0-14
  • 0-acid
  • 7-neutral
  • 14- alkaline
  • lemon juice- 1.5
  • tums- 10

Heating Baking Soda Lab

During the Lab:


  • moisture condensation comes from hot gas touching cooler top of the test tube turning back to a liquid


Control Group:

  • unheated test tube


Experimental Group:

  • heated test tube


Indicator:

  • the tea (showed that heated is no longer b. soda)

Volume Notes

Unit of measurement: cm3



Volume: lxwxh


Volume of Liquids:

  • use a graduated cylinder to measure volume
  • *always check the intervals or scale*
  • units= millileters (mL) or cm3
  • 1mL= 1cm3
  • read from BOTTOM of meniscus

Single Pan Balance Notes

  • check pan is clean and dry
  • always zero balance before massing (push all riders to 0 and use adjustment knob if needed)
  • Never switch pans
  • Pick up balance by red bar only

Box Questions #1-13 skip #2

1. Why do you think baking soda is used in baking?


  • When heated it releases a gas which allows dough/batter to rise


3. How many cubic centimeters of water are required to fill a graduated cylinder to the 50.0mL mark?

  • 50 cm3


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?

  • Rectangle A must have a bigger width and height.


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?

  • 7cm3


6a. How many cubes will be needed to build a cube that measures 2cm along each edge?

  • 24 cubes


6b. How many cubes will be needed to build a cube that measures 3cm along each edge?

  • 36 cubes


6c. What is the volume, in cubic centimeters, of each of the cubes in (a) and (b)?

  • a= 24 mL
  • b= 36 mL

7. One rectangular box is 30cm long, 15cm wide, and 10cm deep. A second rectangular box is 25cm long, 16cm wide and 15cm deep. Which box has the larger volume?

  • The second box


8. Figure A shows a cone-shaped graduate used for measuring the volume of liquids. Why are the divisions not equally spaced?

  • Because the cup gradually gets wider. As the height increases, the surface decreases.


9a. Estimate the position of arrows I and II in figure B(a) to the nearest 0.01cm. Can you estimate their positions to the 0.001 cm?

  • I- 1.2
  • II- 3.7
  • I- 1.19
  • II- 3.78


9b. Estimate the positions of arrows III, IV, and V in Figure B(b) to the nearest 0.01 cm. Can you estimate their positions to 0.001 cm?

  • III- 1.65
  • IV- 2.51
  • V- 4.50
  • III- 1.651
  • IV- 2.510
  • V- 4.501


9c. Why should you report the positions of the arrows in part (b) to the nearest 0.01 cm and not to the nearest 0.1 cm?

  • Because Figure B(b) shows the millimeter marks


10. What part of a cubic centimeter do the smallest divisions on each of the graduated cylinders in Figure C represent? Express your answer as a decimal.

  • a. 0.1
  • b. 0.2


11. What is the level of the liquid in Figure D(a) to the nearest half division? WHat is the level in figure D(b) to the nearest half division?

  • a- 4.0
  • b- 1.3


12. Three students reported the length of a pencil to be 12 cm, 12.0 cm, and 12.00 cm. Do all three readings contain the same information?

  • 12: 11.5-12.4
  • 12.0: 11.95- 12.04
  • 12.00: 11.995-12.004


13. What advantage is there to making graduated cylinders narrow and tall rather than short and wide?

  • Lines farther apart because less surface so need more depth