Matter and Energy

DescriptionConservation LawsPeriodic TableEnergy

Revised 5/11/07

Previous Material

• Accuracy & precision

• Significant Figures

• SI Units LengthMassTemperatureMole

• Conversionswithin MetricEnglish-Metric

• Medical Dose Units

Simple Definitions

• Matter – anything which has mass and occupies space

• Energy – the ability to do work

Copper atoms on silica surface.

• An atom is the smallest particle of an element that has the chemical properties of the element.

Distance across = 1.8 nanometer (1.8 x 10-9 m)

Conservation

• Conservation of Matter - matter is neither created nor destroyed

must account for all matter during a reaction

• Conservation of Energy - energy is neither created nor destroyed, changed from one form to another

must account for all energy

Three States of Matter

• Solid – defined shape and volume• Liquid – adopt shape of container

and defined volume• Gas – adopt shape and volume of

container

(pages 55 – 57, table 2.7, textbook)

Matter ClassificationDescription of Matter

Heterogenous(mixtures)

Elements Compounds

Pure Substances Solutions

Homogenous

Matter

Matter Classification

ElementElement

Pure substance that cannot be Pure substance that cannot be decomposed any further by ordinary decomposed any further by ordinary meansmeansAbout 115 elements listed on Periodic About 115 elements listed on Periodic TableTable

metals, nonmetals, non--metals, metalloids,metals, metalloids,atomic number, atomic symbolatomic number, atomic symbol

Long FormLong Form--Periodic TablePeriodic Table

Periodic TablePeriodic TableDmitri Mendeleev developed the Dmitri Mendeleev developed the modern periodic table. Argued that modern periodic table. Argued that element properties are element properties are periodic periodic functions of their atomic weightsfunctions of their atomic weights..We now know that element We now know that element properties are periodic functions of properties are periodic functions of their their ATOMIC NUMBERSATOMIC NUMBERS..

p.79a

p.79b

Regions of the Periodic TableRegions of the Periodic Table

Group 1A: Alkali MetalsLi, Na, K, Rb, Cs

Group 1A: Alkali MetalsGroup 1A: Alkali MetalsLi, Na, K, Li, Na, K, RbRb, Cs, Cs

Cutting sodium metalCutting sodium metal

MagnesiumMagnesium

Magnesium Magnesium oxideoxide

Group 2A: Alkaline Earth MetalsGroup 2A: Alkaline Earth MetalsBe, Mg, Ca, Be, Mg, Ca, SrSr, , BaBa, Ra, Ra

Group 7A: HalogensF, Cl, Br, I, At

Group 7A: HalogensGroup 7A: HalogensF, F, ClCl, Br, I, At, Br, I, At

Group 8A: Noble Gases He, Ne, Ar, Kr, Xe, RnGroup 8A: Noble Gases Group 8A: Noble Gases He, He, NeNe, , ArAr, Kr, , Kr, XeXe, , RnRn

Group 6A: O, S, Se, Te, PoGroup 6A: O, S, Se, Te, PoGroup 6A: O, S, Se, Te, Po

Sulfuric acid dripping Sulfuric acid dripping from snotfrom snot--titetite in cave in cave

in Mexicoin MexicoElemental S has a ring Elemental S has a ring

structure.structure.

Transition ElementsTransition ElementsTransition Elements

Lanthanides and actinidesLanthanides and actinidesIron in air gives Iron in air gives iron(III) oxideiron(III) oxide

Forms of the ElementsForms of the Elements

Most are Most are monoatomicmonoatomic –– a single atom is the a single atom is the element, examples:element, examples: Zn (s), Al (s), Cs (s)Zn (s), Al (s), Cs (s)Some are Some are DiatomicDiatomic –– two atoms bound two atoms bound together form the element (not single atom together form the element (not single atom shown of Periodic Table)shown of Periodic Table)HH2 2 (g); N(g); N22 (g); O(g); O22 (g); F(g); F22 (g); Cl(g); Cl22 (g); (g); BrBr22 (l); I(l); I22 (s); (s);

Periodic TrendsPeriodic Trends

Properties of elements Properties of elements that may be predicted that may be predicted by relative position on by relative position on Periodic TablePeriodic Table

Metal CharacterMetal CharacterAtomic SizeAtomic SizeIonization EnergyIonization EnergyElectronegativityElectronegativity

See: Pages 99See: Pages 99--101,101,textbooktextbook

Atomic SizeAtomic Size

CompoundCompound

Pure substance composed of two or more Pure substance composed of two or more elements bonded together in a definite ratio by elements bonded together in a definite ratio by weight. weight.

Identified by a unique set of physical and Identified by a unique set of physical and chemical properties.chemical properties.

HH22O and HO and H22OO22

NaNa22CrOCrO44 and Naand Na22CrCr22OO77

CompoundsCompounds

Same three component elements Same three component elements –– Na, Cr, Na, Cr, but different weight ratiosbut different weight ratios

NaNa22CrOCrO44 NaNa22CrCr22OO77

Comparison of Physical PropertiesWater and Hydrogen Peroxide

Water Hydrogenperoxide

Melting point °C 0.0 - 2

Boiling point °C 100 158

Density, g/mL 1.0 1.46

Terms for Matter

• Heterogeneous• Homogeneous• Mixture• Solution• Physical process• Chemical process

• Element• Compound• Atom• Period• Family• Metal

Classification of Energy(pages 40 –41, textbook)

Description of Energy

Potential(position or stored)

Kinetic(motion)

Energy

Forms of Energy

HeatLightElectricity

Energy

ENERGYENERGY is the capacity is the capacity to do work or transfer to do work or transfer heat.heat.

HEATHEAT is the form of is the form of energy that flows energy that flows between 2 objects between 2 objects because of their because of their difference in temperature.difference in temperature.Other forms of energy Other forms of energy ——••lightlight••electricalelectrical••kinetic and potentialkinetic and potential

Gravitational Potential Energy:

E = mgh

h = height

g = * 9.82 m/s2

m = mass

* On Earth

Potential EnergyPotential energy is stored energy and the energy of position––There are

several forms of potential energy. Chemical Energy is energy stored in the bonds of atoms and molecules. It is the energy that holds these particles together. Biomass, petroleum, natural gas, and propane are examples of stored chemical energy. Stored Mechanical Energy is energy stored in objects by the application of a force. Compressed springs and stretched rubber bands are examples of stored mechanical energy. Nuclear Energy is energy stored in the nucleus of an atom––the energy that holds the nucleus together. The energy can be released when the nuclei are combined or split apart. Nuclear power plants split the nuclei of uranium atoms in a process called fission. The sun combines the nuclei of hydrogen atoms in a process called fusion. Scientists are working on creating fusion energy on earth, so that someday there might be fusion power plants.Gravitational Energy is the energy of position or place. A rock resting at the top of a hill contains gravitational potential energy. Hydropower, such as water in a reservoir behind a dam, is an example of gravitational potential energy.

Kinetic EnergyE = 1/2 mv2

E = energy (Joules)m = mass (kilograms)v = speed (meters/sec.)

Marion Jones Sprints to Victory in the 200 meter.

Kinetic Energy

Kinetic energy is motion––of waves, electrons, atoms, molecules, substances, and objects. Electrical Energy is the movement of electrical charges. Electrical charges moving through a wire is called electricity. Radiant Energy is electromagnetic energy that travels in transverse waves. Radiant energy includes visible light, x-rays, gamma rays and radio waves. Light is one type of radiant energy. Thermal Energy, or heat, is the internal energy in substances––the vibration and movement of the atoms and molecules within substances. Geothermal energy is an example of thermal energy. Motion Energy is the movement of objects and substances from one place to another. Wind is an example of motion energy.

Terms for Energy

• Energy• Potential Energy• Kinetic Energy• Heat• Light

• Temperature• Specific Heat• calorie, cal• Wave length