Intro to Physical Science Quiz 9/18

By: Ben Badnani

Whats on the Quiz?

Lab Safety

Reaction in Bag Lab

Baking Soda Lab

Volume Notes

Balance Notes

Box Questions

Lab Safety Notes

Every Lab


Goggles on eyes all time (Until Mr. Leeds says its ok to take off)

Report all accidents or spills immediately

EMERGENCY!


Nurse Extension: 2828


Safety Equipment Classroom


Fire Extinguisher

Fire Blanket

Eye Wash/Shower


Chemicals


NEVER TASTE CHEMICALS

Waft Liquids to detect Odor

NEVER WAFT SOLIDS OR POWDERS!

Don’t physically touch Chemicals

Wash hands with soap after Lab always

Flush skin with water for 1 minute + Notify Mr Leeds if chemical touches skin


Glass

Hot and Cold Glass look the same

Never use chipped or broken glass (Tell Mr. Leeds and put in proper trash)

NEVER USE FORCE TO REMOVE OR INSERT GLASS


Alcohol Burners



What to do?

  1. Roll up sleeves
  2. Put up long hair (Not just pull back)
  3. Never walk away from lit burner
  4. Never point the open end of a hot test tube at someone else or yourself
  5. Don’t look down into test tube/beaker while heated
  6. Burner is capped and flame is out when finished



End of Experiment


(Important Part of Lab or LOSE POINTS)


Clean up area & Materials!

Make sure burner is out!

Keep goggles on until instructed to take them off


Reaction in Bag


  • Phenol Red, Acid
  • Used as a PH Indicator ------> PH SCALE
    • Measures acidity
    • Goes from 0-14
    • 0-7-14
    • Acid-Neutral-Alkaline
      • Examples:
        • Lemon juice


2 SOLIDS


Solid A


  • Calcium Chloride (Calcium + Chlorine)
  • Acidic
  • Hydrotropic
    • Opposite of Hydrofobic
    • Attracted to water
    • Absorbs Water
      • Examples
        • Uses: Canned Veggies----> (Absorbs Water, Keeps fro setting mushy)


  • Elelctrolyte in sports drinks (like gatorade)
  • Used to flavor pickles (Salty)


Solid B

Baking Soda: Sodium Bicarbonate

  • Non Acidic
  • Uses:
    • Uses
    • ToothPaste
    • Laundry Detergent


Heating Baking Soda

Lab 1.1 Heating Baking Soda

Scientific Terms:

Control Group - Unheated Baking Soda + Tea

Experimental Group - Heated Baking Soda + Tea

Indicator: Tea (showed that the heated test tube is not Baking Soda)

Variables: A category you try to measure

Independent Variable: Causes a change in the dependent variable

  • Temperature (Heat), flame
Dependent Variable: Tea color

Control Factors:

  • Same type of Tea
  • Same type of Baking Soda
  • Same amount of Tea
  • Same amount of Baking Soda
  • Same size
  • Same amount of stirring time




Experiment Errors

Hole in tube ----> Won't see the gas fill the bottle


Stopper not snug

Not cleaning stirring rod ----> Contaminate


Extra Question for Lab


Is the amount of condensation more of less than the amount of Baking Soda that is being heated??


Answer: Something cannot produce more than itself. It is less since it is coming from the Baking Soda

Unit of Measurement


Cm3 = Cubic Centimeters


Volume = Length X Width X Height (a x b x c)


Standard Unit of Length = Meter (M)


1 Centimeter (1cm) = 0.1m


Unit Cube

A small cube 1cm on each edge


One Cubic Centimeter (1cm3)


Volume of Liquids:


  • Use a graduated cylinder to measure volume
  • Always check the intervals or scale units = Milliliters (mL) or cm3
    • 1mL = Km3



Balance Notes

1. Check that pan is clean.


2. Always check that is says "ZERO" balance before Each Massing.

3. NEVER Switch Pans!

4. Pick up balance by red bar only.

5. Don't zero balance it when you are done.

Box Questions 1-13 (Except 2)

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



  • Added to cakes, breads cookies, brownies etc. because when it is heated it releases gas allowing it to rise



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


  • 50mL


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?
  • It could be the Height or the Width


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?


  • It is the Volume of the Stone


  • 6. A student has a large number of cubes that measure 1 cm along each edge.

  1. How many cubes will be needed to build a cube that measures 2 cm along each edge.
  • It is 8 cubes
2. How many cubes will be needed to build a cube that measures 3 cm along each edge?
  • It is 27 cubes
3. What is the volume, in cubic centimeters, of each of the cubes in (a) and (b)?
  • 8cm3, 27cm3


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


  • The second one has more volume



8. Figure shows a cone-shaped graduate used to measuring the volume of liquids. Why are the divisions not equally spaced?
  • Because as it goes up, it gets wider. (Surface of liquid getting wider)
  • Height increases depth decreases.


9. The scale in Figure B is in the centimeters


1. Estimate the positions of arrows / and II in Figure B(a) to the nearest 0.1 cm. Can you estimate their positions to 0.01. cm?
  • 1.2, 3.8/ NO
2. Estimate the positions of arrows III, IV, and V in Figure B to the nearest 0.o1 cm. Can you estimate their positions to 0.001 cm?

  • 1.65, 2.50, 4.50
3. Why should you report the positions of the arrows in part (b) to the nearest 0.01 m and not to the nearest 0.1 cm?

  • Will be more accurate

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) .2

B) .1

11. What is the level of 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 cm3

B)1.30 cm3

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

  • 1 11.5-12.4
  • 2 11.95-12.04
  • 3 11.995-12.004
  • Could round from any number after the decimal

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

  • Easier to read because further apart because there is less surface and more depth