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Monday  January 8, 2024   Day 1
Introductions and Chemistry         
                                    



Textbook Readings:

1.1: Atoms and Molecules
1.2: The Scientific Approach to Knowledge
1.3: The Classification of Matter
1.4: Physical and Chemical Changes and Properties

****  1.E: Matter, Measurement, and Problem Solving (Homework)
Kirk's Course Lectures:

1.1  pdf  Video*  Chemical and Physical Change  



Types of Matter
 Chemical and Physical Change  

Chapter 1 objectives

     .....Describe atoms and molecules.
     .....Describe the Scientific method and its important components
          including observation, experiments,  hypothesis, theory, and law
     .... Give examples of the Scientific Method from your problem solving life.
     .....Define  matter and classify it as
                 solid, liquid or gas
                 element or compound
                 pure substance or mixture
                 homogeneous or heterogeneous mixture
     .....Know the difference between physical and chemical change
     .....Correctly identify changes as either chemical or physical changes.

     .....Use your calculator's scientific notation function to perform mathamatical
          calculations correctly.  (EE, EXP, etc.   See video at right)
                
Calculators and Scientific Notation


HOMEWORK QUESTIONS:

1.1. Why are molecules  bigger than atoms.

1.2. Which of the following is a chemical change?
    a. cake baking      b. snow melting      c. gasoline evaporating      d. water boiling       e. sun setting

1.3. On a cold winter day your car doesn't start.  After some thought you conclude the battery is bad and in need of replacement.  This is an example of ...
    a. ...an experiment        b. a law       c. a theory         d. a hypothesis        e. an observation

1.4. Orange juice is an example of ...
    a. compound                 b. a homogeneous mixture      c. a heterogeneous mixture       d.   a solution       e. a pure element

1.5. Milk is considered a heterogeneous mixture and yet it appears homogeneous to the naked eye.  Why heterogeoneous?

1.6. How are liquid water, ice and steam alike?  How are they different on a molecular level? How are they alike?

1.7. Why is a gas compressible whereas a liquid is not?

1.8.  When hydrogen gas (H2) is reacted with oxygen gas (O2), water (H2O) is produced along with a lot of ENERGY.  Is this a chemical or physical change?

1.9.  Electrical energy can be used to convert liquid water into H2 and O2 gas.  Is this a chemical or physcial change?

1.10. Identify each of the following substances as homogeneous or heterogeneous:
     a. Liquid water                b. sugar water        c. pizza           d. oil & water salad dressing         e. beer           f. beach sand          g. Snickers candy bar

1.11.  3D printers melt plastic filement and deposite it accurately to build an object.   If the temperature of the printer is set too high, the plastic will burn and this is an example of a ____________  change.

1.12.  Use your calculator to determine the correct results of the following calculations:

     a.  1.34 x 103      x    5.00 x 10-7                            ==    ?
     b.  9.95 x 10--12   x    6.76 x 10-4                           ==   ?
     c.  127.4               x    1.28 x 1024                          ==   ?
     d.  3.1415             x  (4.67 x 10-27)2                      ==   ?
     e.  4.98 x 1034     x    6.33 x 10-36                         ==    ?
     f.   12.5                 /     4.4 x 10-88                          ==    ?
     g.   5.555 x1045    /    2. x 10-25                             ==     ?
     h.   4.41 E-09       /     2.67 E+07                              ==    ?      (Note "E" is shorthand for "10x")
     i.    6.444 E-14     x     7.98E-05    /    6.3 E+22        ==   ?
     j.    (3.56 E-1   +   4.01 E-2)          /     3.836 E+45   ==   ?    (Watch your order of operations!)
     k.   (9.88 E -31  +  6.81 E -33)     /   (1.23 E+34  +   6.66 E+32)    ==   ?


Click and drag below for answers:

1.1. Molecules are made up of atoms.   
1.2. a. cake baking:  chemical changes taking place....impossible to reverse this change.     
1.3. d. hypothesis: an idea requiring experimental testing    
1.4. c. heterogeneous mixture 
1.5. Under a microscope, milk contains small, visible fat globules ... thus heterogeneous.
1.6. On a molecular level, all contain water molecules (H2O) but in ice, the molecules are held in place (crystaline lattice), in liquid the molecules are moving but still close together, and in steam, the water molecules are moving at high speed and are far apart. 
1.7. Gases contain a lot of empty space between the gas phase molecules or atoms.  In liquids, the molecules or atoms are close together with little space between them.
1.8.  This is a chemical change.  The product is something chemically different from the initial reactants.
1.9.  This is a chemical change.  The product is something chemically different from the initial reactants.
1.10.  a. Homogeneous     b. Homogeneous      c. Heterogeneous     d. Heterogeneous      e. Heterogenious    f. Heterogeneous      g. Heterogeneous
1.11.  Burning:  Chemical change
1.12.   a.   6.70 x 10-4            b.  6.7262 x 10-15            c. 1.63072 x 1026             d.  6.8512659 x 10-53               e.  3.15234 x 10-1
      f.    2.840909 x 1088    g.   2.7775 x 1070             h. 1.651685 E-16              i. 8.1624 E-41               j.  1.032586 E-46            k. 7.67245 E-65
             where non-significant figures are displayed as subscripts
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Tuesday January 9, 2024    Day 2
Energy!!!


Click  HERE  and memorize  these elements and symbols!  (Flashcards can be helpful)

Textbook Readings:

1.5: Energy: A Fundamental Part of Physical and Chemical Change


1.E: Matter, Measurement, and Problem Solving (Homework)

Energy KE and PE
 Conservation of Energy demonstrated
Chapter 1 objectives

     .....Know the definitions for work, energy, kinetic energy, potential energy  thermal energy

     .....Summarize the law of conservation of energy and provide examples demonstrating the idea

     .....Provide standard units for time, length, mass, and temperature

HOMEWORK QUESTIONS:

2.1. Identify the following as potential energy (PE)) or kinetic energy (KE):

      i. AAA battery                  ii. a flowing river         iii. falling rock    iv. light            v. dynamite  

      vi. Snickers candy bar        vii. heat                      viii. sugar           viii. Sound 

2.2. A large rock at the top of a cliff has 3,000. Joules of potential energy.  If the rock is pushed off the cliff, how much kinetic energy will it have just
       before it hits bottom assuming all of the PE is converted into KE?
        a. 0 Joules of kinetic energy       b. 1500 Joules of Kinetic Energy     c. 3000 Joules of Kinetic Energy      d.   6000 Joules of Kinetic Energy

2.3. Which of the following is NOT a form of energy?
     a.  Heat                                     b. temperature                                         c. sound                                           d. light                             e. electricity

2.4  Calculate the KE  in Joules of a 2500. pound car moving at 30.0 miles/hour (Convert pounds to kg and mile/hour to m/s first).

2.5   If the car in question 2.4 collides with a fixed brick wall, its kinetic energy is largely converted into sound and bent metal.  If the sound released has energy equivalent to 2500. J,   how much kinetic energy is available to bend the metal?

2.6  An atom releases 1.5 x 10-18 J of light energy.  How has the atom's energy changed?

2.7  The specific heat of water is 4.184 Joules/goC    This number describes how water responds to added or removed heat energy.  For example, if 4.184 Joules of heat energy
       is acquired by 1.00 gram of water, the water temperature will go up by 1oC.

       a. If 20.92 J of heat energy is acquired by 1 gram of water, what will be the temperature change?
       b. If 4.184 J of heat energy is acquired by 0.5 grams of water, what will be the temperature change?
       c.  If 20.92 J of heat energy is acquired by 2 grams of water, what will be the tempearture change?

2.8  Old-style incandescent light bulbs are not very effcient converting  approximately 5% of the electrical energy into light.  The remaining energy is released as heat energy.  If over a period of 1 hour, the light bulb consumes 3,600 Joules of electrical energy, how much heat energy is released?  Why are incandescent bulbs more desireable in the winter than in the summer?



Click and drag below for answers:
2.1. i.  PE      ii. KE    iii. KE   iv. KE     v. PE     vi. PE     vii. KE     viii. PE      viiii.  KE
2.2. All of the potential energy is converted to 3000 Joules of Kinetic Energy
2.3. b. Temperature.  Temperature is a measure of how hot something is but is not a form of energy.  The coming and going of heat energy produces changes in temperature.
2.4    101,979 Joules  (1.02 x 105 J with 3 significant figures)
2.5    101,979 J - 2500 J  = 99,479 J       (9.9 x 104 J)
2.6   The atom's energy decreases by 1.5 x 10-18 J    This is often denoted with a minus sign ( -1.5 x 10-18 J) to denotea decrease  in  energy
2.7   a. 5 oC     b. 2.0 oC (as there is less water, the heat is able to produce 2X the temperature change as for 1 g water)  c. 2.5oC
2.8  3420 Joules of heat are released.  In the winter, the released heat warms the building and supplements the  furnace which doesn't have to supply that heat).  During the summer, the home's AC unit will have to removed the heat generated by the lightbulb to keep things cool. costing more money,
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Wednesday  January 10, 2024   Day 3
Units, Measurement and Density   

Click  HERE  and memorize  these elements and symbols!  (Flashcards can be helpful)

Textbook Readings:

1.6: The Units of Measurement


1.E: Matter, Measurement, and Problem Solving (Homework)
Course Lectures:

1.2  pdf  Video*  Measurement
1.3  pdf  Video*  Density         


Units
Graduated Scales and Cylinders

Density
Density: Water Displacement

Objectives

1. Memorize the base units of the SI system of measurement.
2. Memorize the Common Unit prefixes, their symbols, and Factors (See text)
3. Apply and convert between prefix/base units
4. Given a graduated scale, determine the increment value (meaning of two adjacent lines)
5. Use a graduated scale to correctly measure length, temperature and volume
6. Calculate density given mass and volume.  Similarly, given any two of these variables, calculate the third.
7. Utilize water displacement to determine the density of an irregularly shaped object.

HOMEWORK QUESTIONS:

3.1  Provide the "factors" for each of the  symbols with their factors      µ    m    c   k    n    p    M    G   d

3.2  Provide the SI units for each of the following:   a. time     b. mass     c. length        d. temperature     e. time

3.3   Why doesn't volume have a fundemental SI unit?

3.4   If the mass of a rock is 3.4 grams and it's volume is 9.5 mL, what are the derived units for density in this case?

3.5  A derived quantity called momentum  is determined by multplying the mass and velocity of an object.  If mass is measured in kilograms and velocity is measured in meters per second, what are the derived units for momentum?

3.6 Another derived quantity is determined by dividing distance (meters) by velocity (m/s).  What are the derived units for this quantity?

3.7 For each of the objects available here, record the correct length with two deciemal places.

3.8  Draw a picture of a 10 mL graduated cylinder that has a 0.1 mL increment.  Then, carefully indicate on your figure the locations correspondng to...
a.  2.69 mL     b.    5.15 mL    c. 9.05 mL       d. 4.00 mL     e. 6.75 mL

3.9  Read the graduated cylinders available here and record your measurements.

3.10  If the mass of an object is 650 g and the volume of that object is 300 ml, what is its density including the correct units?

3.10 An average penny weighs  2.5 grams.  If one penny has a volume of 0.4418 mL, what is the density of the penny?   Determine if the penny will float
        or sink in a mercury filled beaker (Density of mercury = DHg  =  13.56 g/cm3)

3.11 A metal block is heated.  How do the following change for the metal block as it's heated?: i. volume    ii.  mass     iii. density

3.12  Pure gold has a density of 19.3 g/mL.  If a gold ring weighs 15.37 grams, what is the ring's volume in mL?

3.13.  A 112 g metal cube is placed in a graduated cylinder that initially contains 40.00 mL of water. The water level rises to 49.50 mL.
          Use this information to determine the density of the metal cube.

3.14   A (large) graduated cylinder is filled with 45.0 mL of distilled  water. The egg sinks to the bottom and the water level rises to 96.2 mL.
          If the mass of the egg is 52.2 grams, determine  egg's density.   If the same egg is placed in salt water, it floats.  Why?

3.15   The density of a gas can be determined by the formula D = (PM )/ (RT)  where P is pressure, M is molar mass, R is the ideal gas law constant and T is the temperature in Kelvin.  Explain the operation of a hot air balloon in terms of this equation.

Click and drag below for answers: 

3.1  Refer to the text
3.2  Refer to the text
3.3 Because volume is a derived unit involving the repeated application of length (e.g. cm x cm x cm = cm3 = centimeters cubed = cc = mL)
3.4 g/mL
3.5 (kg*m) / s
3.6   s
3.7   ...lookiing forward to checking these answers!  Discuss with classmatws as necessary
3.8  On your own for this one but it will be checked.
3.9  ...lookiing forward to checking these answers!  Discuss with classmatws as necessary
3.10   2.166 g/mL
3.11  a. Volume increases (This is true for many materials as they're heated)     b. Mass remains constant      c.  Density decreases since it is inversely proportional to volume
3.12  0.796 mL
3.13  11.8 g/mL
3.14  1.02 g/mL    Salt water contains dissolved salts and is therefore  more dense than the egg . Therefore, being less dense, the egg floats.  You are actually more buoyant in salt water than in lake water!
3.15 The equation tells us that for a gas, density and temperature are "inversely" related (assuming nothing else changes).  In otherwords, as temperature increases, the density of the gas decreases.  Hot air balloons have large propane fired burners that heat the air in the balloon's envelope.  As the temperature of the gas goes up, the density of the air in the balloon goes down.  As the density of the balloon air is now less than the cooler air around it, the balloon floats.
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Thursday  January 11, 2024  Day 4
Significant Figures and Temperature Conversion 

Click  HERE  and memorize  these elements and symbols!  (Flashcards can be helpful)
Textbook Readings:

1.7: The Reliability of a Measurement


 Course Lectures

1.6  pdf    Video   Rounding
1.7  pdf    Video   Significant Figures:
Our Simplified Rounding
Rules At Right->

We will not be using the text book's rules that utilize
even and odd rouding when the digit to be
dropped is a perfect "5".
 Our Rounding Rules

Rules for rounding
Significant Figures
Significant figures in Calculations
Significant figures and Mixed Calculations
Temperature Conversions
Objectives:

1. Determine correctly the number of significant figures and decimal digits in any measurement.  This includes knowing when "Zeros" are significant and when they are not.

2. Utilize significant figuresin simple multiplication and division calculations to round results correctly.

3. Utilize decimal digits in simple addition and subtraction calculations to round results correctly.

4. Perform mixed calculations involving mult/div   and add/subtr correctly rounding the results based upon sig. fig and decimal digit considerations.

5.  Mathematically convert oC, oF and K temperatures.

6.  Describe and define accuracy vs. precision
HOMEWORK QUESTIONS:

4.1  Determine the number of significant figures in each of the following measurements:
       a.  1.514 km      b.   0.556 g      c.   5.5040 s       d. 0.00159 uL        e. 0.0034500 L      f. 3.45 x 10-3 m     g.   2.4170 x 1023 atoms     h. 9.0800 x 10-4 g

4.2  How many significant figures are there in each of the following measurements?
    a.  1.05 cm     b. 0.034 sec    c. 0.000010 inches      d. 1000 miles        e. 10. acres        f. 1.02 x 105 m       g. 4.5050 x 10 -6 sec     h. 1,000,000 km

4.3  What is the result of the following calculation with the correct number of significant figures?  32.821  +  0.0034   +   121.2

4.4  What is the result of the following calculation with the correct number of significant figures?    100.   -  55.89   +    84.1

4.4  What is the result of the following calculation with the correct number of significant figures?    100   -  55.89   +    84.1      

4.6 What is the result of the following calculation with the correct number of significant figures?  (8.0001 x 102) x (2.88 x 103 ÷ 2.4 x 10-3)   

4.7   What is the result of the following calculation with the correct number of significant figures?  (4.519 x 10-8) / (0.25 + 3.9782)   
      (you will see a problem like #4 ... mixed calculations... on the Exam 1)

4.8  Convert 72.0 oF into Celsius degrees.

4.9  Convert 25.8 oF into Kelvins

4.10  Convert 310. Kelvins into Fahrenheit degrees.

4.11  What does it mean if you have an accurate result?  
        What does it mean if you have a precise series of measurements?
        Can measurements be precise but not accurate?



Click and drag below for answers:

4.1   a. 4 SF     b. 3 SF    c. 5 SF     d. 3 SF     e. 5 SF     f. 3 SF   g. 5 SF     h. 5 SF
4.2  a. 3 SF      b. 2 SF     c. 2 SF     d. 1 SF     e. 2 SF     f. 3 SF   g. 5 SF    h.  1 SF
4.3  154.0244  rounded to one decimal digit 154.0
4.4  128.21     rounded to zero decimal digits  128
4.5   128.21    rounded to 100  (Note decimal point in calculation is missing)
4.6   9.6 x 108 (2 SF all multiplcation or division .... using only SF)
4.7   1.07 x 10-8 (3 SF   The addition in the denominator produces a result with 2 decimal places and 3 SF.  The latter determines the SF of the overall result)
4.8   22.2 oC (3 SF)
4.9   25.8 oC   ----->     - 3.44444 oC (2 SF and one decimal digit)     -----> 269.70556 K rounded to one decimal place.....Final Answer 269.7 K
4.10  98 oF (2 SF)


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Friday  January 12, 2024    Day 5
Dimensional Analysis

Click  HERE  and memorize  these elements and symbols!  (Flashcards can be helpful)
Textbook Readings:

1.8: Solving Chemical Problems
 Course Lectures

1.4  pdf  Video*  Dim analysis and the metric system
1.5  pdf  Video*  Dimensional analysis example

Scientific Notation and Dimensional Analysis
Converting Units with Conversion Factors
HOMEWORK QUESTIONS:


5.1  What is the difference between an exact number and a measurement?  How does an exact number affect the signficant figures in a calculated result?

5.2  Use dimensional analysis to convert 10.0 km into cm. Express your answer in scientific notation.

5.3  Use dimensional analysis to convert 26.6 miles into feet (1 mile = 5280 feet exactly)

5.4  Use dimensional analysis to convert the following
        a. 0.0055 mL -->  uL      b. 12.35 psec --> sec       c. 550 nm ---> m      d. 1.89 x 10-3 m --> km    e. 1.87 x 104 J --> kJ         f. 3,501 Mm   ---> cm

5.5   Use dimensional analysis to convert the following   (1 inch = 2.54 cm exactly)
        a. 100. cm2   --->   ft2            b. 350. inch3  --->   cm3          c.  350. inch3  --->   mL               d.  9.81 cm/s2   ---->    in/s2       e.  9.81 cm/s2   --->   cm/min2

5.6. Convert 25.2 km into inches. 

5.7. Convert 55 miles/hr into m/s.  1 mile = 5280 feet exactly

5.8  Convert the density of water (1.0 g/mL) into  units of kg/L

5.9  Convert the density of water (1.0 g/mL) into units of mg/uL

5.10  Convert the density of water (1.0 g/mL) into units of pounds/gallon   (Useful information:  1 kg = 2.2046 pounds,  1 gallon = 3.78541 liters)
         NOTE:  You are required to know metric conversion factors AND 1 inch = 2.54 cm (exactly)
                        All other conversion factors non-metric conversion factors will be supplied on exams

5.11. Convert 5.50 m/s2 into units of ft/min2     (12 inches = 1 foot       5280 ft = 1 mile)

5.12. How many miles are there in 5340. uhgs?  (1 uhg = 4 miles exactly)


Click and drag below for answers:

5.1  Exact numbers are perfect and have no uncertainty.  They should not in any way affect SF appearing in final calculated results.  Exact numbers are often counted quantities.  For example, there are 12 eggs in a dozen; an exact relationship with no uncertainty.

5.2      1.00 x 106 cm

5.3       1.40 x 105 ft

5.4       a. 5.5 uL     b. 1.235 x 10-11 s      c. 5.5 x 10-7 m     d. 1.89 x 10-6 km     e. 18.7 kJ    f. 3.501 x 1011 cm

5.5       a. 0.108 ft2    b. 5740 cm3                 c. 5740 mL           d. 3.86 in/s2     e. 35300 cm/min2

5.6      992000 inches

5.7    25 m/s

5.8     1.0 kg/L

5.9     1.0 mg/uL

5.10    8.345 pounds/gallon

5.11    6.50 x 104 ft/min2

5.12    21360 uhgs
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