Title: Chapter 1 Chemistry: The Science of Matter
1Chapter 1 Chemistry The Science of Matter
- Section 1.1 The Puzzle of Matter
- Section 1.2 Properties and Changes of Matter
2Section 1.1 Objectives
- Classify matter according to its composition.
- Distinguish among elements, compounds,
homogeneous mixtures, and heterogeneous mixtures. - Relate the properties of matter to its structure.
3Composition, Structure and Behavior
- Chemistry- the science that investigates and
explains the structure and properties of matter. - Matter- anything that takes up space and has mass
- Mass- the measure of the amount of matter that
an object contains
4Matter
- Matter is all around you.
- Phone
- Your neighbor
- The desk
- The metal of your chair
- The air you are breathing
- What isnt matter
- Heat
- Light
- Thoughts
- Ideas
- Radio waves
- Magnetic fields
5Mass
- On earth we equate mass with weight.
- A bowling ball has a larger mass than a tennis
ball. - I have more mass than the text book.
6Matter
- The structure of matter refers to its
composition-what is it made of and how is it
organized - The properties of matter describe the
characteristics and behavior of matter. - Changes matter undergoes
7Comparing Composition and Behavior (Figure 1.2
page 5)
- Salt and Water
- Salt is Na and Cl
- Water is H and O
- You can wash you hair in water, but not in salt.
And you sprinkle water over popcorn. - Aspirin and Sucrose
- Both are composed of C, H, and O
- You wouldnt use aspirin to sweeten cereal or use
sucrose for a headache
8Properties
- You can determine some of the properties of a
particular chunk of matter by examination and
manipulation. - What is its color?
- Is it a solid, liquid or gas?
- Is it soft or hard?
- Does it dissolve in water?
9Properties of Iron
- Strong, but can be flattened and stretched
- Does not dissolve in water
- Turns to a liquid at high temperatures
- Is a gray, shiny solid
- Is attracted to a magnet
- Conduct electricity
10Properties and Composition
- You may be able to determine many properties of a
piece of matter by examining it and doing some
simple tests. - However, you can not determine what it is
composed of just by looking at it.
11Examining Matter The Macroscopic View of Matter
- The macroscopic view of matter is one in which
you touch, smell, taste and see.
12The Submicroscopic View of Matter
- Gives you a glimpse into the world of atoms
- You cannot see this world even with the most
powerful microscopic. - Matter is made up of atoms
- Atoms are so small that a period at the end of a
sentence is made up of 100,000,000,000,000,000,000
(100 quintillion) carbon atoms. - If you could count all 100 quintillion atoms at a
rate of three per second it would take you a
trillion years to finish counting.
13Macro, micro, submicro
- Macroscopic I can see with my naked eye
- Microscopic I need a microscope to see
- Submicroscopic I cant see even with the most
powerful microscope
14Scanning Tunneling Microscope (STM)
- Although you cannot see atoms the STM can produce
images on a computer screen that show the
location of individual atoms. - Platinum
15Using Models in Chemistry
- In chemistry you will use macroscopic and
sub-microscopic models to understand certain
concepts. - Scientific model- a thinking device, built on
experimentation, that helps us to understand and
explain macroscopic observations.
16Models
- A model for the atom was discussed in Greece
about 2,500 years ago. However, this was not a
scientific model. - The scientific model of the atom was not proposed
until the 1800s and it has with stood much
experimentation with little changes.
17Classifying Matter
- Matter can be classified by its composition
- There are two main types of classifications
- Qualitative- an observation made without
measurement. - Quantitative- an observation made with measurement
18Qualitative vs. Quantitative
- Qualitative
- There are students in this room
- Sucrose contains carbon, oxygen and hydrogen
- Quantitative
- There are 24 students in this room
- Sucrose contains 42.1 g of carbon, 51.4 g of
oxygen and 6.5 g of hydrogen.
19Pure vs. Mixture
- Matter can be classified by its purity.
- Is the matter pure or is it a mixture?
- Pure in chemistry means it contains only the same
substance. - Substance- matter with the same fixed composition
and properties. - Can be an element or a compound
- Any sample of pure matter is a substance
20Substances
- The bag of sugar you buy at the store is pure
sucrose. It all has the same properties and a
fixed composition. Therefore, it is a substance.
21Mixed Matter
- Mixed matter is referred to as a mixture.
- Mixture- combination of two or more substances in
which the basic identity of the substances are
not changed. - Mixtures do not have a specific composition.
- Mixtures can be separated into its components by
physical means.
22Separating Mixtures
- One way is by physical changes.
- Physical change- a change in matter that does not
involve a change in the identity of individual
substances. - Boiling
- Freezing
- Melting
- Evaporation
- Dissolving
- Crystallization
23Physical Properties
- Separation by physical changes takes advantage of
the physical properties of the mixture. - Physical properties- characteristics that a
sample of matter exhibits without any changes in
its identity - Solubility
- Melting and boiling point
- Color
- Density
- Electrical conductivity
- Physical state (solid, liquid or gas)
24Types of Mixture
- There are two types of mixtures
- Heterogeneous
- Hetero means different
- Homogeneous
- Homo means the same
25Heterogeneous Mixture
- Heterogeneous Mixture- a mixture that does not
have a uniform composition. - You can see the different composition.
- Examples
- Granite
- Chef Salad
- Lucky Charms Cereal
- Orange Juice with pulp
26Homogeneous Mixture
- Homogeneous Mixture- a mixture with a uniform
composition. - You cannot tell that it is composed of more than
one substance - Another name is a solution
- Examples
- Salt water
- Tea
- Sugar water
27Solutions
- Homogeneous mixture
- Examples
- Salt water
- Gasoline
- Air
- Steel
28Alloys
- Alloys- solid solutions that contain different
metals and sometimes nonmetallic substance - Table 1.1 page 23
29Table 1.1 Some Common Alloys
Name of Alloy Composition
Stainless Steel 73-79 iron (Fe) 14-18 chromium (Cr) 7-9 nickel (Ni)
Bronze 70-95 copper (Cu) 1-25 zinc (Zn) 1-18 tin (Sn)
Brass 50-80 copper (Cu) 20-50 zinc (Zn)
Sterling Silver 92.5 silver (Ag) 7.5 copper (Cu)
14-karat gold 58 gold (Au) 14-28 silver (Ag) 14-28 copper (Cu)
18-karat white gold 75 gold (Au) 12.5 silver (Ag) 12.5 copper (Cu)
Solder (electronic) 63 tin (Sn) 37 lead (Pb)
30Solutions
- When you are dissolving a substance into another
substance there are two important terms - Solute the substance being dissolved
- Solvent the dissolving agent
- Salt Water
- Solute NaCl
- Solvent H2O
31Aqueous Solution
- Aqueous Solution- a solution in which the solvent
is water. - Examples
- Soda
- Tea
- Contact-lens cleaner
- Clear cleaning liquids
- Most processes of life take place in aqueous
solutions.
32Substance Pure Matter
- You and everything around you is made up of
chemicals.
33Elements The Building Blocks
- If you classify an unknown piece of matter as
pure it means that it is made up of one
substance - There are two types of substances
- Compounds
- Elements
34Elements
- Elements- a substance that cannot be broken down
into simpler substances. - Simplest form of matter
- Building blocks for other types of matter
- All substance in the universe are
- Elements
- Compounds formed from elements
- Or mixtures of elements and compound
35Elements
- 118 elements
- Examples
- Gold
- Carbon
- Lead
- Elements combine to form millions of compounds.
- Chemical elements are often referred to as the
building blocks of matter
36Elements
- 118 elements
- 90 occur naturally
- Less than half of these are abundant
- The remainder are synthesized
37Organizing the Elements
- Elements are organized in the Periodic Table
- The periodic table tells you
- Name
- Symbol
- Atomic mass
38Symbols
- The symbols of the elements are extremely
important to know. - You will only have to know the most common ones.
- The symbols are a one to two letter
representation of the elements. - Not all the symbols are the first or second
letter of the elements name
39Symbols
- Oxygen
- O
- Hydrogen
- H
- Bromine
- Br
- Chlorine
- Cl
40Table 1.2 Some Historic Chemical Symbols
Element Symbol Origin Language
Antimony Sb Stibium Latin
Copper Cu Cuprum Latin
Gold Au Aurum Latin
Iron Fe Ferrum Latin
Lead Pb Plumbum Latin
Potassium K Kalium Latin
Silver Ag Argentum Latin
Sodium Na Natrium Latin
Tin Sn Stannum Latin
Tungsten W Wolfram german
41Compounds Are More Than One Element
- Compound a chemical combination of two or more
different elements joined together in a fixed
proportion. - Every compound has its own fixed composition
- Therefore, every compound has unique chemical and
physical properties. - The properties of a compound are different from
the properties of the elements that make them up.
42Compounds
- More than 10 million are known (still growing)
- New natural compounds are being isolated from
plants and colonies of bacteria. - New compounds are also being synthesized in labs.
- Examples
- Sucrose
- Salt
- Water
43Formulas of Compounds
- Formula a combination of the chemical symbols
that show what elements make up a compound and
the number of atoms of each element. - Sucrose Aspartame
44Table 1.3 Some Common Compounds
Compound Name Formula
Acetaminophen C8H9NO2
Acetic Acid C2H4O2
Ammonia NH3
Aspartame C14H18N2O5
Propane C3H8
Salt NaCl
Sodium Hydroxide NaOH
Sucrose C12H22O11
Water H2O
45Review
- What is the difference between an element and a
compound? - What is the difference between a homogeneous
mixture and a heterogeneous mixture? - What is the difference between a mixture and a
compound?