El Camino College Chemistry 21A Dr. Dragan Marinkovic CHEMISTRY 21A Survey of General and Organic Chemistry Dr. Dragan Marinkovic [email protected]

El Camino College Chemistry 21A Dr. Dragan Marinkovic

CHEMISTRY 21ASurvey of General and Organic Chemistry

Dr. Dragan [email protected]

Spring Semester 2009

El Camino College, Torrance, CA


Dragan ≠


Dragan ≠

Dragan = +

(pronounce as)


CHEMISTRY

H2O, NaCl

Systematic (IUPAC) name

(2α, 4α, 5β, 7β, 10β, 13α)- 4, 10- bis(acetyloxy)- 13- {[(2R, 3S)- 3- (benzoylamino)- 2- hydroxy- 3- phenylpropanoyl] oxy}- 1, 7-

dihydroxy- 9- oxo- 5, 20- epoxytax- 11- en- 2- yl benzoate

TAXOL® (paclitaxel)

water table salt


CHEMISTRYMedicines containing derivatives of salicylic acid, structurally similar to aspirin, have been in medical use since ancient times. Salicylate-rich willow bark extract became recognized for its specific effects on fever, pain and inflammation in the mid-eighteenth century.

In 1897, scientists at the drug and dye firm Bayer began investigating acetylsalicylic acid as a less-irritating replacement for standard common salicylate medicines. By 1899, Bayer had dubbed this drug Aspirin and was selling it around the world. The name Aspirin is derived from A = Acetyl and "Spirsäure" = an old (German) name for salicylic acid.

At the beginning of 20th century heroin was touted as a wonder drug promising to solve all of life's maladies ranging from tuberculosis to a disagreeable stomach.


Question: What Is Chemistry?

Answer: If you look 'chemistry' up in Webster's Dictionary, you'll see:

"chem·is·try n., pl. –tries”

1. the science that systematically studies the composition, properties, and activity of organic and inorganic substances and various elementary forms of matter.

2. chemical properties, reactions, phenomena, etc.: the chemistry of carbon.

3. a. sympathetic understanding; rapport. b. sexual attraction.

4. the constituent elements of something; the chemistry of love.

CHEMISTRY


Chemistry (from Egyptian kēme (chem), meaning "earth“

1)Chemistry is the science concerned with the composition, structure,

and properties of matter, as well as the changes it undergoes

during chemical reactions.

2) Chemistry is a physical science for studies of various atoms, molecules, crystals and other aggregates of matter whether in isolation or

combination, which incorporates the concepts of energy and

entropy in relation to the spontaneity of chemical processes.

Modern chemistry evolved out of alchemy after the

chemical revolution (1773)

CHEMISTRY


Disciplines within chemistry include

Inorganic chemistry, the study of inorganic matter

Organic chemistry, the study of organic matter

Biochemistry, the study of substances found in

biological organisms

Physical chemistry, the energy related studies of

chemical systems at macro, molecular and

submolecular scales

Analytical chemistry, the analysis of material samples to

gain an understanding of their chemical composition

and structure.

Medicinal or pharmaceutical chemistry is a discipline

at the intersection of chemistry and pharmacology involved with designing, synthesizing and developing pharmaceutical drugs.

CHEMISTRY


Why Study Chemistry?

Because understanding chemistry helps you to understand the world around you. Cooking is chemistry. Everything you can touch or taste or smell is a chemical.

When you study chemistry, you come to understand a bit about how things work.

Chemistry isn't secret knowledge, useless to anyone but a scientist.

It's the explanation for everyday things, like why laundry detergent works better in hot water, or how baking soda works, or why not all pain relievers work equally well on a headache.

If you know some chemistry, you can make educated choices about everyday products that you use.

CHEMISTRY


CHEMISTRY 21A

The real importance of Chemistry is that it serves as the interface to practically all of the

other sciences, as well as to many other areas of human endeavor.

For this reason, Chemistry is often said (at

least by chemists!) to be the "central science".

Chemistry can be "central" in a much more

personal way: with a solid background in Chemistry, you will find it far easier to

migrate into other fields as your interests develop.

Chemistry: the central science


CHEMISTRY

HEALTH SCIENCES

NUTRITION

MICROBIOLOGY

BOTANY

PHYSIOLOGY

MATERIALS SCIENCE

CHEMISTRY


CHEMISTRY 21A

Chemistry 21A is the first semester of a two-semester sequence designed to provide students with the skills and knowledge needed to satisfy the requirements for several allied health related majors, especially the pre-Nursing major. This course presents the fundamental principles of inorganic chemistry and begins the study of organic chemistry.

Chemistry 21A fulfills the chemistry prerequisite for Biology 1B, Microbiology 33, and Physiology 31, and provides the foundation necessary for success in Chemistry 21B (the second course in the sequence).


CHEMISTRY 21AMaterials:1 . Seager and Slabaugh, Chemistry for Today: General, Organic, and Biochemistry, 6th Ed.

2. Campbell, Chemistry 21A Packet

3. Peller, Exploring Chemistry: Laboratory Experiments in General, Organic, and Biological Chemistry, 2nd Ed.

4. Safety goggles (Instructor approved - do not purchase until "fitted" in class)

5. Calculator (able lo handle exponential notation calculations and logarithms)

6. OPTIONAL: Study Guide and Solutions Manual for Seager and ,Slabaugh's Chemistry for Today: General, Organic, and Biochemistry 5th Ed.

7. A set of different colored pens or pencils is recommended for note taking!


CHEMISTRY 21A

Grading: Final letter grades will generally be assigned according to the following percentage of total points

earned:

Grade -- Percent A 90 - 100% B 80 - 90% C 65 - 80% D 55 - 65% F below 55%

Approximate distribution of points:Tests (3 @ 100 points each) ...........................................

300Quizzes (9 @ 20 points each) .........................................

180Laboratory (total points) .................................................

240Assignments/Other ................................... . ...................

30Final Exam ..................................................................

250Course Total ..................................................................

1000


CHEMISTRY 21A

Is it possible to do lots of hard work and have fun at the same time?


CHEMISTRY 21A


Maybe?


CHEMISTRY 21A


Maybe?

Maybe not?


CHEMISTRY 21A

But, we can certainly try and make the best of this very scientific course.

You will have to learn many new definitions, visualize many abstract concepts and start thinking like a scientist.

I compare learning chemistry to learning a foreign language. You have to learn words before you can speak. So, new chemical words are waiting for you!

I’ll try my best and I expect you will try your best too!

I am here to help you learn, and I MEAN IT! Let me know how I can help you learn.


Maybe?

Maybe not?


CHEMISTRY 21A



CHEMISTRY 21A


However, I am not going to give out “easy passes”.

Please, be prepared and ready for work.

Be attentive. (No cell phones, video games,snacks or fixing make-up during classes!)

Ask relevant questions!


CHEMISTRY 21A


I am here to help you learn, and I MEAN IT!

Let me know how I can help you learn.

However, I am not going to give out “easy passes”.

Please, be prepared and ready for work.

Be attentive. (No cell phones, video games,snacks or fixing make-up during classes!)

Ask relevant questions!


MATTER

Chemistry is the science concerned with the

composition, structure, and properties of matter, as well as the changes it undergoes during chemical reactions.


MATTER

Matter is anything that has mass and volume (occupies space).



Matter is basically everything around us, us included.

The amount of matter measured by its resistance to acceleration (movement)


MATTER






Mass is a measurement of matter present.


MATTER






Mass is a measurement of matter present.

Weight is a measurement of the gravitational force acting on an object.


MATTER

Characteristics of objects: shape, size, color…

(scientific terms): PROPERTIES OF MATTER

Physical properties can be observed or measured without changing the composition of matter.

Physical properties are used to observe and describe matter.

Physical properties include: appearance, texture, color, odor, melting point, boiling point, density, solubility, polarity, and many others.


MATTER

Chemical property is any of a material's properties that becomes evident during a chemical reaction.

Chemical property is any quality that can be established only by changing a substance's composition.

Simply speaking, chemical properties cannot be determined just by viewing or touching the substance.

The substance's internal structure must be affected for its chemical properties to be investigated.


MATTER

Physical properties :

NO CHANGE in the composition of matter.

Chemical properties :

CHANGE in the composition of matter.


SCIENTIFIC METHOD

Scientific method refers to bodies of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge.

To be termed scientific, a method of inquiry must be based on gathering observable,

empirical and measurable evidence subject to specific principles of reasoning. A scientific method consists of the collection of data through observation and experimentation, and the formulation and testing of hypotheses.

The essential elements of a scientific method are:

Characterizations (observations, definitions, and measurements of the subject of inquiry)

Hypotheses (theoretical, hypothetical explanations of observations and measurements of the subject)

Predictions (reasoning including logical deduction from the hypothesis or theory)

Experiments (tests of all of the above)

•Gather information and resources (observe)•Form hypothesis•Perform experiment and collect data•Analyze data•Interpret data and draw conclusions that serve as a starting point for new hypothesis•Publish results•Retest (frequently done by other scientists)


MEASUREMENTS

MEASUREMENTis a process to attach a numericalvalue to an observation. This is done to be able to compare or order two or more such observations.


MEASUREMENTS

MEASUREMENT UNITNUMBER +

(hr, oz, oF, ft, gal, $)(3, 16, 8.9)



MEASUREMENTS

MEASUREMENT UNITNUMBER +

(hr, oz, oF, ft, gal, $)(3, 16, 8.9)


Units of Measurement provide standards to compare against.


MEASUREMENTS

UNITS of length


MEASUREMENTS

The METRIC SYSTEM

Internationally adopted in 1960.

The METRIC SYSTEM is a DECIMAL system

length METERmass KILOGRAMvolume LITRE

Imperial Units

length FOOT, YARD, MILEmass OUNCE, POUNDvolume FLUID OUNCE, GALLON

(US units of measurement)

The fluid ounce in Britain is smaller than the fluid ounce in the US, but the US gallon is smaller than the British gallon

1 foot = 12 inches 1 yard = 3 feet (plural of foot) = 36 inches 1 mile = 1760 yards = 5280 feet

1 meter = 1000 millimeters 1 kilometer = 1000 meters


MEASUREMENTS

The SI decimal prefixesOwing to the wide range of values that quantities can have, it has long been the practice to employ prefixes such as milli and mega to indicate decimal

fractions and multiples of metric units. As part of the SI standard, this system has been extended and formalized.

prefix abbreviation multiplier -- prefix abbreviation Multiplier

exa E 1018 deci d 10–1

peta P 1015 centi c 10–2

tera T 1012 milli m 10–3

giga G 109 micro μ 10–6

mega M 106 nano n 10–9

kilo k 103 pico p 10–12

hecto h 102 femto f 10–15

deca da 10 atto a 10–18


MEASUREMENTS

Units of measurement provide standards to compare against.

Basic unit of measurementis a specific unit from which other units for the same quantity are obtained by multiplication or division.


MEASUREMENTS

Units of measurement provide standards to compare against.

Basic unit of measurementis a specific unit from which other units for the same quantity are obtained by multiplication or division.

Derived unit of measurementis a unit obtained by multiplication or division of oneor more basic units.

e.g. area = (length)(length) = (length)2 volume = (length)(length)(length) = (length)3


MEASUREMENTS

Conversion Factors for Units of Length1 inch = 2.54 centimeters1 foot = 0.305 meter1 yard = 0.914 meter1 mile = 1.609 kilometers1 nautical mile = 1.852 kilometers1 centimeter = 0.39 inch1 meter = 39.37 inches = 3.28 feet = 1.094 yards1 kilometer = 0.62 miles Conversion Factors for Units of Volume

1 cubic inch = 16.4 cubic centimeters1 cubic foot = 0.0283 cubic meter1 cubic yard = 0.765 cubic meter1 fluid ounce = 29.6 milliliters1 U.S. pint = 0.473 liter1 U.S. quart = 0.946 liter1 U.S. gallon = 3.8 liters1 cubic centimeter = 0.06 cubic inch1 cubic meter = 1.3 cubic yards1 milliliter = 0.034 fluid ounce1 liter = 1.06 U.S. quarts


MEASUREMENTS

Conversion Factors for Units of Weight or Mass

1 grain = 64 milligrams1 ounce = 28.35 grams1 pound = 0.45 kilogram 1 gram = 0.035 ounce 1 kilogram = 2.205 pounds 1 metric ton = 1.1 short ton

Standard1 lb = 0.45359237 kg1 kg = 2.204622621849 lb 1 kg = 35.27396194958 oz


MEASUREMENTS

Celsius

Fahrenheit

Kelvin

Temperature Conversion

°C = (100/180) X (°F - 32)°F = (1.8 X °C) + 32°K = °C + 273.15°C = °K - 273.15°K = [(100/180) X (°F - 32)] + 273.15°F = [1.8 X (°K - 273.15)] + 32


MEASUREMENTS/ENERGY

Energy Units Conversions

British Thermal Unit

Foot-pounds

Joules caloriesKilo-

caloriesKilowatt-

hours

1 British Thermal Unit 1 777.9 1055 252.0 0.252 2.93x10-4

1 Foot-pound 0.001285 1 1.356 0.3238 3.238x10-4 3.766x10-7

1 joule 9.481x10-4 0.7376 1 0.2388 2.388x10-4 2.778x10-7

1 calorie 0.003969 3.088 4.187 1 0.001 1.163x10-6

1 kilocalorie 3.969 3088 4187 1000 1 0.001163

1 kilowatt hour 3413 2.655x106 3.6x106 8.598x105 859.8 1

energy (from the Greek ἐνέργεια - energeia "activity, operation", from ἐνεργός - energos, "active, working") is a scalar physical quantity that describes the amount of work that can be performed by a force.

Energy is an attribute of objects and systems that is subject to a conservation law. Several different forms of energy exist to explain all known natural phenomena. These forms include (but are not limited to) kinetic, potential, thermal, gravitational, sound, light, elastic, and electromagnetic energy. The forms of energy are often named after a related force. Any form of energy can be transformed into another form, but the total energy always remains the same.


ENERGYThe forms of energy are kinetic, potential, thermal, gravitational, sound, light, elastic, and electromagnetic energy. KINETIC ENERGY

The energy a particle has asA result of its motion.

1KE = ----- mv2

2

POTENTIAL ENERGY

The energy a particle has asA result of attractive or repulsive forces acting on it.

COHESIVE FORCE

The attractive force between particles; it is associated with potential energy.

DISRUPTIVE FORCE

The force resulting from particles motion; it is associated with kinetic energy.


MEASUREMENTS






Conversion Factors for Units of Volume

1 cubic inch = 16.4 cubic centimeters1 cubic foot = 0.0283 cubic meter1 cubic yard = 0.765 cubic meter1 fluid ounce = 29.6 milliliters1 U.S. pint = 0.473 liter1 U.S. quart = 0.946 liter1 U.S. gallon = 3.8 liters1 cubic centimeter = 0.06 cubic inch1 cubic meter = 1.3 cubic yards1 milliliter = 0.034 fluid ounce1 liter = 1.06 U.S.quarts

Conversion Factors for Units of Length

1 inch = 2.54 centimeters1 foot = 0.305 meter1 yard = 0.914 meter1 mile = 1.609 kilometers1 nautical mile = 1.852 kilometers1 centimeter = 0.39 inch1 meter = 39.37 inches = 3.28 feet = 1.094 yards1 kilometer = 0.62 miles


MEASUREMENTS

High accuracy, but low precision

High precision, but low accuracy

ACCURACY is a MEASURE of the degree of agreement between a MEASURED value and TRUE value of the dimension measured.

PRECISION is a MEASURE of the degree of agreement between a SUCCESSIVE MEASUREMENTS of the SAME property of the SAME item.

All measurements are subject to two kinds of errors:

1. ERRORS due to the measuring instrument

2. ERRORS due to the person doing the measuring


CALCULATING PERCENTAGES

What is a percentage?

Percent means “for every 100” or "out of 100." The (%) symbol as a quick way to write a fraction with a denominator of 100. As an example, instead of saying "it rained 14 days out of every 100," we say "it rained 14% of the time."

12 people out of a total of 25 were female. What percentage were female?

The price of a $1:50 candy bar was to be increased by 20%. What was the new price?


MEASUREMENTS

The PERCENTAGE ERROR tells the degree of accuracy of your work, the agreement between your value and accepted value of the measurement.

(accepted value) – (experimental value)% error = --------------------------------------------------------- x 100

accepted value

(actual value) – (estimated value)% error = --------------------------------------------------------- x 100

actual value


LARGE AND SMALL NUMBERSScientific notation is simply a method for expressing, and working with, very large or very small numbers.

5.67 x 105

This is the scientific notation for the standard number, 567 000. Now look at the number again, with the three parts labeled.

5.67 x 105 coefficient base exponent

1. The coefficient must be greater than or equal to 1 and less than 10.2. The base must be 10.3. The exponent must show the number of decimal places that the decimal needs to be moved to change the number to standard notation. A negative exponent means that the decimal is moved to the left when changing to standard notation.

Changing numbers from scientific notation to standard notation. Ex.1 Change 6.03 x 107 to standard notation.

remember, 107 = 10 x 10 x 10 x 10 x 10 x 10 x 10 = 10 000 000 so, 6.03 x 107 = 6.03 x 10 000 000 = 60 300 000

answer = 60 300 000Instead of finding the value of the base, we can simply move the decimal seven places to the right

because the exponent is 7.So, 6.03 x 107 = 60 300 000

Now let us try one with a negative exponent.Ex.2 Change 5.3 x 10-4 to standard notation.

The exponent tells us to move the decimal four places to the left.so, 5.3 x 10-4 = 0.00053


LARGE AND SMALL NUMBERS

Rule for Multiplication - When you multiply numbers with scientific notation, multiply the coefficients together and add the exponents. The base will remain 10.

Ex 1. Multiply (3.45 x 107) x (6.25 x 105)first rewrite the problem as: (3.45 x 6.25) x (107 x 105)

Then multiply the coefficients and add the exponents: 21.5625 x 1012

Then change to correct scientific notation: 2.16 x 1013

NOTE - we add one to the exponent because we moved the decimal one place to the left.

Rule for Division - When dividing with scientific notation, divide the coefficients and subtract the exponents. The base will remain 10.

Ex. 1 Divide 3.5 x 108 by 6.6 x 104 rewrite the problem as: 3.5 x 108

--------- 6.6 x 104

Divide the coefficients and subtract the exponents to get: 0.530303 x 104 Change to correct scientific notation to get: 5.30303 x 103

Note - We subtract one from the exponent because we moved the decimal one place to the right.

Rule for Addition and Subtraction - when adding or subtracting in scientific notation, you must express the numbers as the same power of 10. This will often involve changing the decimal place of the coefficient.

Ex. 1 Add 3.76 x 104 and 5.5 x 102 move the decimal to change 5.5 x 102 to 0.055 x 104

add the coefficients and leave the base and exponent the same: 3.76 + 0.055 = 3.815 x 104


SIGNIFICANT FIGURES

"The population of our city is 157,872.""The number of registered voters as of Jan 1 was 27,833."

= RELIABLE FIGURES


SIGNIFICANT FIGURES


The first statement cannot possibly be correct. Even if a city’s population could be defined in a precise way (Permanent residents? Warm bodies?), how can we account for the minute-by minute changes that occur as people are born and die, or move in and move away?

= RELIABLE FIGURES


SIGNIFICANT FIGURES


The first statement cannot possibly be correct. Even if a city’s population could be defined in a precise way (Permanent residents? Warm bodies?), how can we account for the minute-by minute changes that occur as people are born and die, or move in and move away?

Making sure that numbers make sense

157900 (the significant digits are underlined here) implies that the population is believed to be within the range of about 157850 to about 157950. In other words, the population is 157900±50. The “plus-or-minus 50” appended to this number means that we consider the absolute uncertainty of the

population measurement to be 50 – (–50) = 100. We can also say that the relative uncertainty is 100/157900, which we can also express as 1 part in 1579, or 1/1579 = 0.000633, or about 0.06 percent.

The value 158000 implies that the population is likely between about 157500 and 158500, or 158000±500. The absolute uncertainty of 1000 translates into a relative uncertainty of 1000/158000 or 1

part in 158, or about 0.6 percent.

= RELIABLE FIGURES


SIGNIFICANT FIGURES

A significant digit is all the numerals in a measured quantity (counting from the left) whose values are considered as known exactly, plus one more whose value could be one more or one less.

The concept of significant digits has less to do with mathematics than with our confidence in a measurement.

Rounding off always leads to the loss of numeric information, what we are getting rid of can be considered to be “numeric noise” that does not contribute to the quality of the measurement.

The purpose in rounding off is to avoid expressing a value to a greater degree of precision than is consistent with the uncertainty in the measurement.

= RELIABLE FIGURES


SIGNIFICANT FIGURES

The concept of significant digits has less to do with

mathematics than with our confidence in a measurement.

It is "six point something": more than six but less than seven. With certainty we can say it is in the range of 6 to 7. Exactly where in that range is a estimate. We might guess it is 40% of the way, just less than halfway, between 6 and 7 or 6.4.

If we had more marks on the scale we could make a better guess.

It is clear that our estimate was close, but the measurement still does not align with a mark. Not only that, but we are having trouble reading the marks now because they are so fine. Now we can estimate with a higher precision that the measurement is 6.39, although you might say that it is 6.38 or even 6.40. Whatever it is, your best guess is 'correct' although it is not certain.Note the distinction between 6.4, 6.40, and 6.400. The three numbers indicate that the measurements were made with three different instruments. If you don't understand why they are different carefully readthe section on significant figures below.


SIGNIFICANT FIGURES

The rules for rounding off

If the first non-significant digit is less than 5, then the least significant digit remains unchanged. If the first non-significant digit is greater than 5, the least significant digit is incremented by 1. If the first non-significant digit is 5, the least significant digit can either be incremented or left unchanged, All non-significant digits are removed.


SIGNIFICANT FIGURES

The rules for rounding off

If the first non-significant digit is less than 5, then the least significant digit remains unchanged. If the first non-significant digit is greater than 5, the least significant digit is incremented by 1. If the first non-significant digit is 5, the least significant digit can either be incremented or left unchanged, All non-significant digits are removed.

number to round /no. of sig. digits result comment

34.216 / 3 34.2 First non-significant digit (1) is less than 5, so number is simply truncated.

2.252 / 2 2.2 or 2.3

First non-significant digit is 5, so least sig. digit can either remain unchanged or be incremented.

39.99 / 3 40.0 Crossing "decimal boundary", so all numbers change.

85,381 / 3 85,400 The two zeros are just placeholders

0.04597 / 3 0.0460 The two leading zeros are not significant digits.


SIGNIFICANT FIGURES

EXACT NUMBERS have no uncertainty

NUMBERS from defined relationships counting NUMBERS

NUMBERS that are part of reduced simple fractions (1/3, 5/9)

1 foot = 12 inches

There are 100 years in a century.

= RELIABLE FIGURES


USING UNITS IN CALCULATIONS

FACTOR-UNIT METHOD a systematical approach

(a.k.a. FACTOR-LABEL METHOD to solving numerical

or DIMENSIONAL ANALYSIS) problems.

How many inches in 3.0 feet ?

(given)(conversion) = answer

or Let's take 2.56 quarts and find out how many liters it is.



Which of the following is the longest length?

3.005 x 103 decimeters

1.522 x 10-3 megameters

6.563 x 104 inches

3.122 x 108 micrometers

3.242 x 102 feet






6.563 x 104 inches


3.242 x 102 feet






6.563 x 104 inches


3.242 x 102 feet






6.563 x 104 inches


3.242 x 102 feet






6.563 x 104 inches


3.242 x 102 feet






6.563 x 104 inches


3.242 x 102 feet






6.563 x 104 inches


3.242 x 102 feet








Conversion Factors for Units of Volume

1 cubic inch = 16.4 cubic centimeters1 cubic foot = 0.0283 cubic meter1 cubic yard = 0.765 cubic meter1 fluid ounce = 29.6 milliliters1 U.S. pint = 0.473 liter1 U.S. quart = 0.946 liter1 U.S. gallon = 3.8 liters1 cubic centimeter = 0.06 cubic inch1 cubic meter = 1.3 cubic yards1 milliliter = 0.034 fluid ounce1 liter = 1.06 U.S.quarts

Conversion Factors for Units of Length

1 inch = 2.54 centimeters1 foot = 0.305 meter1 yard = 0.914 meter1 mile = 1.609 kilometers1 nautical mile = 1.852 kilometers1 centimeter = 0.39 inch1 meter = 39.37 inches = 3.28 feet = 1.094 yards1 kilometer = 0.62 miles


MATTER

Matter exists in three distinct physical states:

GAS

LIQUID and

SOLID


MATTER

Gases take the shape of a container and fully fill the (closed) container – i.e. have the same

volume as the inside of the container.

Solids retain the shape regardless of the size or shape of the container they are in.

Liquids take the shape of a container, but retain their volume.


MATTER

Scientific models are explanation of observed behaviour.

A MODEL OF MATTER

All matter is made up of particles that are too small to see. These particles are named MOLECULES.

MOLECULES are the smallest particle of pure substance that has properties of that substance and is capable of stable independent existence.

MOLECULE is the limit of physical subdivision for a pure substance.Any further separation has to be done chemically creating new entities that would not have the properties of the larger sample.

The smaller particles that make up MOLECULES are called ATOMS.

Basic concepts of MODEL OF MATTER:


MATTER

A MODEL OF MATTER

3. Compounds consisted of atoms of different elements combined together.

4. Compounds have constant composition because they contain a

fixed ratio of atoms and each atom has its own characteristic weight, thus fixing the weight ratio of one element to the other.

5. Chemical reactions involve the rearrangement, separation or combinations of atoms, but the atoms are never created or destroyed

John Dalton developed first ATOMIC THEORY (1808).

1. Elements (and all matter) consist of tiny particles called atoms. 2. All atoms of an element are identical and they have the same mass.

The reason elements differ from one another is that atoms of each

element are different from one another; in particular, they have different masses.


MATTER

A MODEL OF MATTER

John Dalton developed first ATOMIC THEORY (1808).

Various atoms and molecules as depicted in John Dalton's A New System of Chemical Philosophy (1808).


MATTER

A MODEL OF MATTER

carbon dioxide

nitrogen carbon monoxide

ammonia

diatomic molecules

homoatomic

heteroatomic

triatomic

polyatomic


MATTER

water, sugar, table salt, carbohydrates, electrolytes (110 mg sodium, 30 mg potassium, 93 mg chloride), high fructose corn syrup, artificial colors, glucose, fructose


MATTER


MATTER

PURE SUBSTANCEMatter that has

constant composition and fixed properties

ELEMENTS

COMPOUNDS


MATTER

MIXTUREPhysical blend of matter

that technically can bephysically separated into two or more components

HOMOGENEOUS MATTERMatter that has the

same properties throughout the sample

HETEROGENEOUS MATTERMatter with propertiesthat are not the samethroughout the sample


MATTER

MIXTUREPhysical blend of matter

that technically can bePhysically separated into two or more components

HOMOGENEOUS MATTERMatter that has the

same properties throughout the sample

SOLUTION

Homogeneous mixture of two or more pure substances


DENSITY

Each box has the same volume. If each ball has the same mass, which box would weigh more? Why?


DENSITY


The box that has more balls has more mass per unit of volume. This property of matter is called density.

The density of a material helps to distinguish it from other materials.


DENSITY


The box that has more balls has more mass per unit of volume. This property of matter is called density.

The density of a material helps to distinguish it from other materials.

mass mdensity ------------ = ------ = d

volume V

High density: iron, lead, gold

Low density: styrofoam, fat, wood

Material Density(gm/cm3)

Water at 4oC 1.0000Water at 20oC 0.998Ice at 0oC 0.92Gasoline 0.70Mercury 13.6Milk 1.03Magnesium 1.7Aluminum 2.7Copper 8.3-9.0Gold 19.3Air 0.001293Carbon dioxide 0.001977Carbon monoxide 0.00125Hydrogen 0.00009Helium 0.000178Nitrogen 0.001251


DENSITY

mass mdensity ------------ = ------ = d

volume VSpecific gravity is defined as the ratio of the density of a given solid or liquid substance to the density of water at a specific temperature and pressure, typically at 4°C (39°F) and 1 atm (760.00 mmHg) , making it a dimensionless quantity.

dsubstance

SG = ---------- dwater

Balsa wood has a specific gravity of 0.2, so it is 0.2 times as dense as water. Aluminum has a specific gravity of 2.7, so it is 2.7 times as dense as water. Lead has a specific gravity of 11.35, so it is 11.35 times as dense as water. Mercury has a specific gravity of 13.56, so it is 13.56 times as dense as water.



MATTER


Documents

El Camino College Chemistry 21A Dr. Dragan Marinkovic CHEMISTRY 21A Survey of General and Organic Chemistry Dr. Dragan Marinkovic [email protected]