1. INTRODUCTION and CHAPTER ONE
General Chemistry 200
INTRODUCTION and CHAPTER ONE
Read the Introduction and Chapter 1.
Chemistry is NOT a spectator sport. Work out complete solutions for all the bold numbered problems.

2. Welcome to the World of Chemistry

3. Beginning Chemistry 200 Read the book before class!
Study the examples and do the practice exercises.
Be prepared for each class session, lecture and laboratory.
Don’t get behind.

4. Outline for Chapter 1 Definitions Homogenous and Heterogeneous
Matter ?
3 states of matter
Chemical –vs.- Physical Change
Calculations
Density
Temperature
Kelvin  Celsius  Fahrenheit
Fahrenheit  Celsius  Kelvin
Significant Figures (Sig Figs)

5. Matter

6. Mixtures (a)Heterogeneous (b)Suspension (c)Homogenous Cookie Blood
Salt water

7. The Language of Chemistry
CHEMICAL ELEMENTS - pure substances that cannot be decomposed by ordinary means to other substances.
Aluminum
Bromine
Sodium

8. The Language of Chemistry
The elements, their names, and their symbols are given on the
PERIODIC TABLE
How many elements are there?

9. The Periodic Table
Dmitri Mendeleev ( )

10. Sodium
Find sodium, Na, on the chart.

11. Copper atoms on silica surface.
An atom is the smallest particle of an element that has the chemical properties of the element.
Copper atoms on silica surface.
Find copper on the chart.

12. The Atom
An atom consists of a nucleus (of protons and neutrons) and electrons in space about the nucleus.
Electron cloud
Nucleus

13. CHEMICAL COMPOUNDS
are composed of atoms and so can be decomposed to those atoms.
The red compound is composed of • Ni- Nickel • C- Carbon • O- Oxygen • N- Nitrogen
Fixed composition

14. MOLECULE The smallest unit of a compound that retains the chemical characteristics of the compound.
MOLECULAR FORMULA
Composition of molecules
C8H10N4O2 - Caffeine
H2O

15. The Nature of Matter Mercury Gold Hg Au
Chemists are interested in the nature of matter and how this is related to its atoms and molecules.

16. Graphite layer structure of carbon atoms reflects physical properties.

17. We can write SYMBOLS to describe these worlds.
Chemistry & Matter
We can explore the MACROSCOPIC world
— what we can see —
Understand the PARTICULATE world
— we cannot see —
We can write SYMBOLS to describe these worlds.

18. A Chemist’s View Macroscopic Particulate Symbolic-
2 H2(g) + O2 (g) --> 2 H2O(g)

20. STATES OF MATTER
SOLIDS — have rigid shape, fixed volume. External shape can reflect the atomic and molecular arrangement.
Reasonably well understood.
LIQUIDS — have no fixed shape and may not fill a container completely.
Not well understood.
GASES — expand to fill their container.
Good theoretical understanding.

21. THE THREE STATES OF MATTER
Bromine (gas)
Aluminum (solid)
Water or H2O (liquid)

22. KINETIC NATURE OF MATTER
Matter consists of atoms and molecules in motion.

23. Physical Properties What are some physical properties? Color
Melting and boiling point
Odor
Conductivity
Density

24. Physical Changes Some physical changes would be boiling of a liquid
melting of a solid
dissolving a solid in a liquid to give a homogeneous mixture

25. DENSITY - an important and useful physical property=
mass ( g )
volume cm 3
Gold
19.3 g/cm3
13.6 g/cm3
Mercury

26. Which is more dense?

27. Relative Densities of the Elements

28. Sig Figs
Sig Fig PPT

29. Density = mass ( g ) volume cm 3
Problem: A piece of copper has a mass of g. It is 9.36 cm long, 7.23 cm wide, and 0.95 mm thick. Calculate density (g/cm3).

30. 95 mm • 1cm 10 mm 0.095 cm3 . = (9.36 cm)(7.23 cm)(0.095 cm) = 6.4 cm3
SOLUTION
1. Get dimensions in common units.
2. Calculate volume in cubic centimeters.
3. Calculate the density. 95 mm •
1cm
10 mm
0.095 cm3 . =
(9.36 cm)(7.23 cm)(0.095 cm) = 6.4 cm3
6.4 cm3
57.54g =
9.0g/cm3

31. PROBLEM: Mercury (Hg) has a density of 13. 6 g/cm3
PROBLEM: Mercury (Hg) has a density of 13.6 g/cm3. What is the mass of 95 mL of Hg? In grams? In pounds?
Solve the problem using DIMENSIONAL ANALYSIS.

32. PROBLEM: Mercury (Hg) has a density of 13. 6 g/cm3
PROBLEM: Mercury (Hg) has a density of 13.6 g/cm3. What is the mass of 95 mL of Hg?
First, note that 1 cm3 = 1 mL
Then, use dimensional analysis to calculate mass. 95 cm 3 •
13.6 g =
1.3 x 10 g
See next slide
What is the mass in pounds?

33. The milliliter and the cubic centimeter are equivalent
The milliliter and the cubic centimeter are equivalent. Notice the units of 10’s.
back

34. PROBLEM: Mercury (Hg) has a density of 13. 6 g/cm3
PROBLEM: Mercury (Hg) has a density of 13.6 g/cm3. What is the mass of 95 mL of Hg?
What is the mass in pounds? (1 lb = 454 g)
1.3 x 10 3 g •
1 lb
454 g =
2.8 lb

35. Density
PROBLEM: An object weighing g is placed in water starting at 6.8 mL, then displaces water to 20.2 mL. What is the density of the object?
20.2
6.8
20.2mL - 6.8mL = 13.4mL

36. PROBLEM: An object weighing 15. 67 g is placed in water starting at 6
PROBLEM: An object weighing g is placed in water starting at 6.8 mL, then displaces water to 20.2 mL. What is the density of the object? 1
15.67g
= 1.17g/cm3
( )ml

37. Chemical Properties and Chemical Change
Burning hydrogen (H2) in oxygen (O2) gives H2O.

38. Chemical Properties
Similar to Physical Properties only with reference to a Chemical reactions
Heat and or light produced
Color
Oder

39. Chemical Properties and Chemical Change
Burning hydrogen (H2) in oxygen (O2) gives H2O.
Chemical change or chemical reaction involves the transformation of one or more atoms or molecules into one or more different molecules.

40. Chemical Change
2 Al Br2
Al2Br6

41. Electrolyzing water

42. UNITS OF MEASUREMENT
We make QUALITATIVE observations of reactions — changes in color and physical state.
We also make QUANTITATIVE MEASUREMENTS, which involve numbers.
Use SI units — based on the metric system

43. UNITS OF MEASUREMENT Use SI units — based on the metric system
length (meter, m)
mass (kilogram, kg, and gram, g)
time (second)

44. Units of Length 1 kilometer (km) = ? meters (m)
1 meter (m) = ? centimeters (cm)
1 centimeter (cm) = ? millimeter (mm)
1 nanometer (nm) = 1.0 x 10-9 meter
O—H distance =
9.4 x m
9.4 x 10-9 cm
0.094 nm
94 pm

45. Measurement Learn the prefixes in Table 1.4 Other Relationships
1 cm3 = 1 mL = L
1.00 lb = 454 g
1.00 in = 2.54 cm
1.06 qt = 1.00 L
Significant figures Page 47
Precision and accuracy Page 43
Examples

46. Temperature Scales Fahrenheit Celsius Kelvin Anders Celsius 1701-1744
Lord Kelvin
(William Thomson)

47. Temperature Scales
Notice that 1 Kelvin degree = 1 degree Celsius

48. Calculations Using Temperature
Generally require temp’s in Kelvin
T (K) = t (°C)
Body temp = 37 oC = K
Liquid nitrogen = oC = 77 K

49. In Class Problems
A rectangular box has dimensions of cm  15.0 cm  8.00 mm. Calculate the volume of the box in liters.
A standard sheet of paper has dimensions of 8.5 inch by 11 inch. A sheet of paper weighs on the average g and has a density of g/cm3. Calculate the thickness of the paper in cm.
A gallon (3.78 L) of latex paint can cover 385 ft2 of the surface of a wall. What is the average thickness of one coat of paint (in micrometers)?

50. Sample problems
Calculate the volume of 525 g of mercury, d=13.534g/cm3.
The melting point of tin is K. Calculate the Celsius temperature.
Find the symbol for gold and the element name for K.
An iron sheet is 3.50 cm square and has a mass of g. The density of iron is 7.87 g/cm3. Calculate the thickness of the iron sheet in mm.
The End!

51. Dimensional Analysis “English-English” (one conversion) 1) 6 in = ? ft
2) 3.5 gal = ? qt
3.5 gal
4 qt
1 gal
= 14 qt

52. Dimensional Analysis “Metric-Metric” (one conversion) 1) 5.0 cm = ? mm
2) 4.0 dg = ? kg
4.0 dg
1 kg
104 dg
= x 10-4 kg

53. Dimensional Analysis “Metric-English” (one conversion)
1) cm = ? in
200.0 cm
1.00 in
2.54 cm
= in
2) 34 qt = ? L
34 qt
1.00 L
1.06 qt
= L

54. Dimensional Analysis “English-English” (two or more conversions)
1) 6 in = ? mile
6 in
1 ft
12 in
1 mile
5280 ft
= 9 x 10-5 mile
2) 3.5 gal = ? oz
32 oz
1 qt
3.5 gal
4 qt
1 gal
= oz

55. Dimensional Analysis “Metric-Metric” (two or more conversions)
1) 5.0 cm = ? km
5.0 cm
1 m
100cm
1 km
1000 m
= x 10-5 km
2) 4 kg = ? pg
103 g
1 kg
1012 pg
1 g
4 kg
= x 1015 pg

56. Dimensional Analysis “Metric-English” (two or more conversions)
1) 200 m = ? in
200 m
100 cm
1 m
1.00 in
2.54 cm
= in
2) 34 qt = ? mL
103 mL
1 L
34 qt
1.00 L
1.06 qt
= x 104 mL

57. Dimensional Analysis “Derived Unit Conversions” Area
1) 8.0 ft2 = ? cm2
(2.54)2 cm2
1.00 in2
8.0 ft2
144 in2
1 ft2
= cm2
2) 2.3 cm2 = ? nm2
2.3 cm2
1014 nm2
1 cm2
= 2.3 x 1014 nm2

58. Dimensional Analysis “Derived Unit Conversions” Volume
1) 445 dm3 = ? mL
445 dm3
103 cm3
1 dm3
1 mL
1 cm3
= x 105mL
2) 5 cm3 = ? mm3
5 cm3
103 mm3
1 cm3
= 5 x 103 mm3

59. Dimensional Analysis “Other Conversions Problems”
1) 100. km/hr = ? mile/hr
1 mile
5280 ft
105 cm
1 km
1.00 in
2.54 cm
1 ft
12 in
100. km hr
= mile/hr
2) 25 m/gal = ? nm/qt
109 nm
1 m
1 gal
4 qt
25 m
gal
= x 109 nm/qt

60. Dimensional Analysis “Other Conversions Problems” (continue)
3) Calculate the density of a material if 45 mL of it has a mass of 128 g.
128 g
45 mL
= 2.8 g/mL
4) Calculate the volume in mL of 2.5 g of a material that has a density of 3.65 g/mL.
2.5 g mL
3.65 g
= mL

61. Dimensional Analysis “Other Conversions Problems” (continue)
5) Calculate the mass of 20 L of a material that has a density of 8.54 g/mL.
20 L
103 ml
1 L
8.54 g ml
= x 105 g
6) How many grams of gold are in 48 g of an alloy that is 22.1% gold?
48 g alloy
22.1 g gold
100.0 g alloy
= g gold

62. Practice Problems 1) 6.45 m = ? cm 2) 12.4 kg = ? mg 3) 184 oz = ? g
4) 24 oz/hr = ? L/day
5) Determine the volume (in L) of 2 kg of sodium chloride. (density = g/mL)
6) How many grams of brass contain 50.0 g of zinc? (This brass contains 15% Zn)
1) 645 cm 2) 1.24 x 107 mg 3) 5220 g 4) 17 L/day
5) 0.9 L 6) 330 g
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