unit 2 lesson #1 types of matter. matter anything that has mass & take up space mass =...
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Unit 2 Lesson #1Types of Matter
Matter Anything that has mass &
take up space
Mass = measurement of the amount of matter an object contains
Chemistry = the study of matter & the changes that it undergoes
Classifying Matter
Quantitative – numerical information
how much, how little, how big, how small
Qualitative – descriptive information
condition, color, size, shape, odor, texture
Matter Flowchart
MATTER
Can it be physically separated?
Homogeneous Mixture
(solution)
Heterogeneous Mixture Compound Element
MIXTURE PURE SUBSTANCE
yes no
Can it be chemically decomposed?
noyesIs the composition uniform?
noyes
Pure Substances
Every sample has same:1. Characteristic properties
2. Composition
Are made of: 1. one type of atom: element
Ex: iron, gold, oxygen
2. Two or more types of atoms: compound Ex: salt, sugar, water
Which are pure substances?
Element Simplest form of matter that has its own unique
set of properties Can not be separated into simpler substances
by physical or chemical means Each element is made up of a single type of
atom
ex. hydrogen, nitrogen, lead
Compound1. A substance that contains 2 or more elements
chemically combined in a fixed proportion (Law of Definite Proportion) Ex.
2. Properties are different than the individual elements
ex. Glucose (sugar)
Glucose – sweet, white solidCarbon – black, tasteless solidOxygen – colorless, tasteless gas Hydrogen – colorless, tasteless gas
Breaking Down Compounds Physical methods do not work Recall…
Chemical changes – a change that produces matter with a different composition than the original matter
Symbols & Formulas Chemical Symbol
each element is represented by a one- or two-letter symbol
Trends:1st letter = always capitalized2nd letter (for an element) = always lowercaseSubscripts = indicate the relative proportions of the elements
in a compound
H K Au H2O C6H12O6
Hydrogen Potassium Gold Water Glucose
Mixtures1. A combination of 2 or more types of matter2. Each component keeps its own identity & properties 3. Components are only physically mixed & can be separated using physical means
Chicken noodle soup
Cinnamon & Sugar
Air
Types of Mixtures1. Heterogeneous mixture -
a mixture in which the substances are not evenly distributed
Salad
Ice tea with ice
Oil & vinegar
2. Homogeneous mixture –
a mixture or ‘solution’ in which the substances are evenly distributed
Kool-Aid
Water
Stainless Steel
Phase – used to describe any part of a sample with uniform composition & properties
Homogeneous mixture
1 phase
Heterogeneous mixture
2 phases
Practice Examples:
graphite
pepper
sugar (sucrose)
paint
soda
Type of Matter
element
hetero. mixture
compound
hetero. mixture
solution
1. Filtration – a technique that uses a porous barrier to separate a solid from a liquid
Can you think of any common applications?
Separating Mixtures
‘Plays’ on differences in physical properties
2. Distillation – a technique that can be used to physically separate most homogeneous mixtures based on differences in the boiling points of the substances involved
3. Chromatography – a technique that is used to physically separate the components of a mixture based on the tendency of each component to travel or be drawn across the surface of another material
Crystallization
Separation technique that results in the formation of pure solid particles from a solution containing the dissolved substance
As one substance evaporates, the dissolved substance comes out of solution and collects as crystals
Produces highly pure solids Rocky candy is an example of
this
Practice Examples:
tea
muddy water
fog
saltwater
Italian salad dressing
Answers: Solution
Heterogeneous
Heterogeneous
Solution
Heterogeneous
Substances vs. Mixtures
Unit 2 Lesson #2Properties of Matter
Properties of Matter1. Extensive – a property that depends on the amount of
matter in a sample ex. mass, volume, amount of energy 2. Intensive – a property that depends on the type (or
identity) of matter in a sample ex. hardness, density, boiling point, electrical
conductivity
Substances – matter that has uniform & unchanging composition have identical intensive
properties… Why?
because every sample has the same composition
Extensive vs. Intensive
Examples:
boiling point
volume
mass
density
conductivity
Answers:
intensive
extensive
extensive
intensive
intensive
3. Physical Properties – a characteristic that can be observed or measured w/out changing the identity of a substance
ex. color, odor, taste, hardness, density, melting/boiling points, state of matter
States of Matter – the physical forms in which all matter exists on Earth
Can you identify these 3 states?
Solid def. shape & volume shape
independent of container
particles are packed together
Liquid def. volume shape depends on container particles can move freely
Gas indefinite volume & shape particles move quickly & spread apart
Chemical Properties Chemical Property
describes the ability of a substance to undergo changes in identity
any of the properties of matter that may only be observed and measured by performing a chemical change or chemical reaction.
Ex. heat of combustion, reactivity with water, pH
Properties of Copper
Physical vs. Chemical Properties
Examples:
melting point
flammable
density
magnetic
tarnishes in air
Answers:
physical
chemical
physical
physical
chemical
Unit 2 Lesson #3Changes in Matter
Phase Changes Evaporation =
Condensation =
Melting =
Freezing =
Sublimation =
Liquid -> Gas
Gas -> Liquid
Solid -> Liquid
Liquid -> Solid
Solid -> Gas
All Physical Changes
Physical Change – a change that occurs in the physical
appearance of a substance, but does not change its identity
breaking, splitting, grinding, cutting, crushing
Ex. melting, boiling, freezing, evaporating, dissolving, condensing
Physical Changes
Chemical Properties – relates to a substance’s ability to undergo changes that transform it into a different substance easiest to see when a chemical is reacting
Chemical changes – a change that produces matter with a different composition than the original matter
ex. burning, rotting, rusting, reacting, cooking, digestion, respiration
Chemical Changes
The process of photosynthesis is a chemical reaction in which light energy, carbon dioxide and water, are transformed to create glucose and oxygen.
The photosynthetic chemical reaction can be shown by writing out the element symbols for each compound.
Reactants substances to the left of the arrow ‘ingredients’ CO2 and H2O
Products substances to the right of the arrow ‘what is made’ or produced C6H12O6 and O2
1. Ammonium Chloride + Water
2. Sodium Bicarbonate + Calcium Chloride
3. Sodium Bicarbonate + Acetic Acid
Did a Chemical Reaction Occur?
Recognizing Chemical Changes
1. Transfer of energy
Energy may be given off
in the form of heat or light
2. Change in color
or odor
Substances may
‘brown’ Indicators
How can you tell whether a chemical change
has taken place?
3. Precipitate
A solid that settles
out of a liquid mixture
4. Gas production
Indicated by the formation
of ‘gas bubbles’
1. Ammonium Chloride + Water
NH4Cl(s) + H2O(l) + Heat ----> NH4 + (aq) + Cl -(aq) + H2O(l)
2. Sodium Bicarbonate + Calcium ChlorideNaHCO3(s) + CaCl2(s) ----> CaCO3(s) + NaCl(aq) + HCl (aq)
3. Sodium Bicarbonate + Acetic Acid NaHCO3(s) + CH3COOH(aq) ----> NaCH3COO-
(aq) + CO 2(g) + H2O(l)
Did a Chemical Reaction Occur?
Physical vs. Chemical Changes
Examples:
rusting iron
dissolving in water
burning a log
melting ice
grinding spices
Answers:
chemical
physical
chemical
physical
physical
Law of Conservation of Matter During any chemical reaction, the mass of the
products is always equal to the mass of the reactants
+ O2
+ CO2 + H2O vapor
I. Law of Conservation of Mass
Although chemical changes occur, mass is neither created nor destroyed in a chemical reaction
Mass of reactants equals mass of productsmassreactants = massproducts
A + B C
Conservation of mass also applies to physical changes…
10g of ice 10g of liquid H2O