Flashcards for Unit 1. Anything that has mass & occupies space. Matter.
Matter… has mass and occupies space. Mass is the amount of matter an object contains. Mass...
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Transcript of Matter… has mass and occupies space. Mass is the amount of matter an object contains. Mass...
Matter…
has mass and occupies space. Mass is the amount of matter an object contains. Mass never changes, but weight does.
The States of Matter
Matter exists in three states: Solid: a rigid substance with a definite shape Liquid: has a definite volume but takes the shape
of its container Gas: takes the shape and volume of its container
Matter can be classified as a mixture or a pure substance.
- Only one substance- Uniform and definite composition- All samples have identical physical properties
- Two or more substances mixed together- Indefinite composition- Can be physically separated into pure substances
- Only one type of element- Cannot be chemically separated into simpler substances
- More than one type of element chemically bonded together- Can be chemically separated into elements
Glucose
C6H12O6
CO2
H2H2O
FePb
Elements…
• contain only one type of atom
Each element has a name and a symbol.
The symbol usually consists of the first one or two letters of the element’s name.
Sometimes the symbol is taken from the element’s original Latin or Greek name.
Examples: oxygen O krypton Kr
Examples: gold Au aurum lead Pb plumbum
Compounds
• Compounds are substances that contain two or more different types of elements.
In general, the properties of compounds are quite different from those of their component elements.
Example:
Table salt is NaCl (sodium + chlorine), while sodium (Na) is a soft metal that acts explosively with water and chlorine (Cl) is a pale yellow- green poisonous gas
- Solutions(one phase)- Looks the same throughout- Uniform composition- Evenly mixed
- Suspensions(two phases)- Looks different throughout (chunks)- Not uniform in composition- Will usually settle over time
Muddy water
Tea Steel
Saltwater
Sample Problem – 1.1 Classify each of the following as an element, a compound, or a mixture:
a. spaghetti sauceb. milk shakec. table sugard. river watere. airf. nitrogen
Sample Problem – 1.2Which of the following are …homogeneous? …heterogeneous?
spaghetti sauce glass muddy water cough syrup
Separating Mixtures
Mixtures can be separated into pure substances by various means.
Separation of Mixtures
• Distillation – a liquid is boiled to produce a vapor that is then condensed again to a liquid.
•
Separation of Mixtures
filtration
Physical Properties
Any characteristic of a substance that can be observed or measured without changing the composition of the substance.
Ex: density, viscosity, melting point, boiling point, taste, hardness, color, odor
Chemical Properties –
describe a substance’s ability to change to a different substance.
Ex. burning, rusting, decomposing, fermenting, exploding and corroding
Intensive property- does not depend on the size of the system or the amount of material in the system.Examples- temperature, color, hardness, melting point, pressure and density
Extensive property- directly proportional to the amount of material in the system.Examples- mass, volume, length and total charge
Physical Change
A physical change involves a change in one or more physical properties but no change in composition.
The original substance is still the same material.
Liquid
Water
Water
VaporSolid
Water
Water is still H2O in all phases. Therefore, phase changes are physical changes!
Chemical Change
A chemical change transforms a substance into one or more new substances.
Cutting Wood
Burning Wood
Rain (water vapor => liquid water)
Melting Gold
Rust
Molding Bread
Chewing apple
Digestingapple
Sparkler
Dissolving Kool-Aid powder in water
Simplifying Mixtures and Compounds
The separation of a mixture is a physical change (such as distillation, filtration).
Breaking down a compound into simpler substances is a chemical change (such as decomposition).
Sample Problem – 1.3
Describe how a mixture of iron filings and aluminum filings can be separated. Is this process a physical or chemical change?
Sample Problem – 1.4
What physical properties could be used to separate a mixture of iron filings and salt?
Sample Problem – 1.5
State several physical or chemical properties that could be used to distinguish between each of the following pairs of substances.
a. gasoline and waterb. copper and silverc. water and salt water solutiond. aluminum and steel
Law of Conservation of Mass
Mass is neither created nor destroyed in a chemical or physical process.
reactants products
Mass reactants = Mass products
“What goes in, must come out!”
Mass of Reactants(before reaction)
Mass of Products(after reaction)
Reaction occurs
Notice the mass before and after the reaction are the same.
Law of Conservation of Mass
hydrogen + oxygen water
How much water is produced when 4.8 grams of hydrogen reacts completely with 38.4 grams of oxygen?
(Answer: 43.2 grams)
Summary: The Organization of Matter