Energy & MatterEnergy & Matter2.1, 1.1, 1.2, 1.32.1, 1.1, 1.2, 1.3
1. Energy (2.1)A. Energy: The capacity to do work or produce
heat.1. 7 types of energy:
• mechanical• thermal (heat)• radiant (light)• sound• electrical• chemical• nuclear
2. Kinetic Energy: Energy of motion.
Ex. thermal,
mechanical
3. Potential Energy: stored energy; determined by position.
Ex. Electrical PE, chemical PE
Potential and Kinetic Energy
4. Energy can be transferred from a system to its surroundings.
Ex. Photosynthesis is light → chemical
Energy Transformations:
5. Energy absorbing changes are called endothermic. If energy is released the change is called exothermic.
B. Measuring Energy:B. Measuring Energy:
1. Common Unit: 1. Common Unit: caloriecalorie The amount of The amount of heatheat needed to raise needed to raise 11 g of water g of water 11 ooC. (One C. (One calorie = 1g°C)calorie = 1g°C)
2. SI Unit for energy: 2. SI Unit for energy: JouleJoule (J) (J)
C. Law of Conservation of Energy:C. Law of Conservation of Energy: Energy is neither Energy is neither ccreatedreated nor nor destroyeddestroyed, it just , it just
changes changes formform. .
Temperature (2.1):Temperature (2.1):
1. Energy can be transferred in the form of 1. Energy can be transferred in the form of
heatheat. .
2. Temperature is a measurement of heat or 2. Temperature is a measurement of heat or
kinetic energykinetic energy. (how fast the average . (how fast the average
particle is moving!)particle is moving!)
Heat vs. Temperature AnimationHeat vs. Temperature AnimationKinetic Energy (Temperature) and MeltingKinetic Energy (Temperature) and Melting
3. Common TemperaturesFahrenheit (F) Celsius (°C) Kelvin (K)
Background InformationPopular
(1686-1736)
scientists
(1701-1744)
SI Unit
Absolute scale
(1824-1907)
Boiling Point of Water 212 100 373
Body Temperature 98.6 37 310
Room Temperature 70 20 293
Freezing Point of Water 32 0 273
Absolute Zero -459.67 -273 0
Room Temp 20°C →
Room Temp 70°F →
← Room Temp 293 K
98.6°F
4. Kelvin:4. Kelvin: °C = K°C = K
5. The zero point on the Kelvin scale is called 5. The zero point on the Kelvin scale is called absolute zeroabsolute zero ( (--273°C) 273°C)
6. All motion of particles 6. All motion of particles stopsstops! Therefore the ! Therefore the kinetickinetic energy is energy is zerozero..
K = °C + 273
°C = K - 273
2. 2. MatterMatter is anything that has is anything that has massmass and takes up and takes up spacespace..1.1. Volume Volume: Amount of : Amount of spacespace an object takes up. an object takes up.
2.2. Mass Mass: Quantity of : Quantity of mattermatter in a substance. in a substance. ConstantConstant everywhere. Ex) the moon everywhere. Ex) the moon
3. 3. WeightWeight: Force produced by : Force produced by gravitygravity acting on a acting on a mass. This is mass. This is differentdifferent in different locations. in different locations.
Mass Vs. WeightMass Vs. Weight
Mass does not depend on gravity. The mass of an object remains the same in all locations.
Weight depends on gravity. Weight equals Mass x gravity. The weight of an object changes with location.Weight and Mass Demo
B. Properties of Matter (1.2):
1. Physical: density, color, melting point, viscosity, surface tension, specific heat
2. Chemical: flammability, reactivity with other
chemicals or air (O2)
C. States of Matter (1.1):
State Shape Volume Movement Structure
Solid definite definite vibrational - slow highly organized - crystal
Liquid indefinite definite translational - medium medium - fluid
Gas indefinite indefinite translational - fast low - random
Plasma is the 4th state of matter – “ionized gas” like the sun
D. Kinetic Theory of Matter (2.1)D. Kinetic Theory of Matter (2.1)
1. 1. GasesGases possess the greatest amount of kinetic energy. possess the greatest amount of kinetic energy.
2. Two factors that determine the state of matter of a 2. Two factors that determine the state of matter of a substance: substance: speed of the particlesspeed of the particles and the and the distance distance between thembetween them..
3. These two factors contribute to the 3. These two factors contribute to the attractionattraction between the between the particles.particles.
4. Substances 4. Substances changechange phasephase when they overcome these when they overcome these attractions.attractions.
5. The overall 5. The overall kinetickinetic energyenergy (temperature) will remain (temperature) will remain constant until the entire substance has completely constant until the entire substance has completely changed phase. changed phase.
6. Heating Curve for Water6. Heating Curve for Water
melting
freezing0
(C)
100Vaporization
(boiling/evaporation)
condensation
Solid
Liquid
Vapor (gas)
Cooling Curve
Heating Curve
E. Changes in Matter (2.1): E. Changes in Matter (2.1):
1.1. Physical Changes Physical Changes:: a. Do NOT change the a. Do NOT change the identityidentity of the substance. of the substance. b. Often change what the b. Often change what the substancesubstance looks like. looks like. c. Examples: c. Examples: cutting, dyeing, changes of statecutting, dyeing, changes of state
States of Matter & Phase Changes
melting
freez
ing
condensation
vaporizationevaporation –at the surface
boiling - throughout
depositionsublimation
Solid
Liquid Gas(Vapor)
States of Matter
Comparison of the three states of matter
Density = .92g/mL
Density = 1.00g/mL
22. Chemical Changes. Chemical Changes::a. Alter the a. Alter the identityidentity of the substance. of the substance.b. The new substance has b. The new substance has different propertiesdifferent properties than the original substance.than the original substance.c. Examples of Chemical Changes: c. Examples of Chemical Changes: burning, rustingburning, rustingd. Signs that a chemical change has occurred:d. Signs that a chemical change has occurred:
1. 1. gas released (bubbles/odor/fizz/smoke)gas released (bubbles/odor/fizz/smoke)2. 2. color change (can be physical too)color change (can be physical too)3. 3. formation of a precipitate (insoluble solid that formation of a precipitate (insoluble solid that
falls out of solution.)falls out of solution.)4. 4. temperature change temperature change (can be physical also) (can be physical also)
F.F. Law of Conservation of Matter (2.2): Law of Conservation of Matter (2.2): Matter is neither Matter is neither createdcreated or or destroyeddestroyed it just changes it just changes formform..
G. Classification of Matter (1.3)G. Classification of Matter (1.3)
1. 1. Pure substancesPure substances: Substances that have a : Substances that have a uniqueunique set of set of
physicalphysical and and chemicalchemical properties. properties.
a. a. ElementsElements: The smallest part of an element is : The smallest part of an element is
an an atomatom..
1. Cannot be separated into 1. Cannot be separated into simpler substancessimpler substances..
2. Represented by 2. Represented by symbolssymbols that have that have 11 or or 22 letters. letters.
Ex) K, Na, Au, Ag, Hg, FeEx) K, Na, Au, Ag, Hg, Fe
(three lettered symbols are temporary)(three lettered symbols are temporary)
3. Examples:3. Examples:
1H
Hydrogen
1.008
Atomic Number: # of protons
Element Symbol: 1 or 2 letters (1st is a capital)
Element Name
Atomic Mass: (weighted average of all an elements’s isotopes)
b. b. CompoundsCompounds::1. Made up of 1. Made up of 22 or more kinds of atoms or more kinds of atoms
chemicallychemically combined in a fixed proportion. combined in a fixed proportion.2. Represented by 2. Represented by formulasformulas..
3. Examples: 3. Examples: CO, COCO, CO22, H, H22OO
2. Mixtures:2. Mixtures:a. a. Heterogeneous MixtureHeterogeneous Mixture: Visibly : Visibly differentdifferent
throughout. Will separate upon standing.throughout. Will separate upon standing.
Ex) Ex) salad dressing (salad dressing (emulsionemulsion), ), chocolate chocolate
chip cookies, sand & water (chip cookies, sand & water (suspensionsuspension))
b. b. Homogeneous MixtureHomogeneous Mixture: The : The samesame
throughout. May be clear, will not separate.throughout. May be clear, will not separate.
Ex) Ex) Kool-aid (Kool-aid (solutionsolution))
milk (milk (colloidcolloid))
gold jewelry (gold jewelry (alloyalloy))
Examples of AlloysExamples of Alloys
Brass is an alloy of copper and zinc.
Steel is an alloy of carbon and iron.
Bronze is an alloy of copper and tin.
Gold – Element & Alloys
Microscopic look at mixtures
Suspensions Colloids Solutions Alloys
ex) sand & water ex) milk ex) Kool-Aid ex) gold jewelry
H. Separating Mixtures (1.3)
1. Heterogeneous Mixtures can be separated by:
a. Filtration- Material remaining on the filter paper is called the residue. The filtrate goes through the filter paper. Ex) sand & water
Separation of Homogeneous Mixtures:
a. Distillation- separates liquids (and 1 solid) by differences in boiling point. The remaining material is called the residue. The material that goes through is called the distillate.
Ex) alcohol & H2O
Another Look at Distillation
• Distillation Demo
• A Closer Look at Distillation
Separation of Homogeneous Mixtures
b. Crystallization- Evaporate liquid and the solid will crystallize. Ex) salt and water
c. Chromatography – used to separate pigments and ink by differences in solubility (density) on a strip of paper.Ex) black ink - rainbow
Another look at Paper Chromatography
3. Separating Compounds:
a. Electrolysis – decomposes a compound into its elements. Ex) water into H2 and O2