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Solid/low energy/small movement

Liquid/more energy/more movement

Gas/high energy/large movement

A large amount of energy added to gas results in a..?

Gain or lose energy.

Example: When air is cooled condensation occurs as the molecules slow down and come together.

Example 2: When water is heated it boils on the stove changing water from liquid state to gas.

Convection is the transfer of heat by

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Heat rising and cooler substances sinking. A good example would be convection cells in the air and water boiling in a pot.

NOTE: Gases and liquids are good convection materials because they are free to move about and transfer the heat.

Periods

[image]Valence electron levels and their chemical properties are similar because of this.

Bonds are broken

Examples: 

Oxidation also known as Rust

Flammability also known as Burning

Bonds Remain Intact

Substance properties remain the same

Example:

Breaking or cutting up a substance

Change of state from solid to liquid

Reading and element block[image]

Atomic number=protons +

(Every positively charged proton will attract a negatively charged electron)

The Mass Number=protons and neutrons=mass

Protons and neutrons each weigh about one amu (atomic mass unit)

Electrons have too small a mass (weight here on Earth) to matter

Make predictions about how things will behave under certain conditions.

Example: Will sodium and chlorine bond or explode?

Can we build this bridge with this design and material?

Bottom to top and left to right

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Protons and neutrons are all attracted to each other as a result - the strong nuclear force. This is an attractive force that only has an effect over a very short range in the nucleus. The strong nuclear force binds protons & neutrons together to make the nucleus.

Go to the following web site and review the development of atomic theory

http://www.hyperhistory.com/online_n2/people_n2/science_n2/atomic_theory.html

New experiments verify or refine previous models and new data is gathered.

Allows us to predict atomic behavior in most circumstances

Will change as we get new information and technology improves

What are valence electrons?

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The Roman numerals found above each group specify the usual number of valence electrons.

That is the number of electrons in the outer most electron shell.

Full shells are unreactive or shells that have stable octets (8)

Is creativity important in science?

Yes, it is needed to solve problems and designing scientific models for unseen phenomena and forming new hypothesis.

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Halogens Family 17

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• Very high electronegativities
• Seven valence electrons (one short of a stable octet)
• Highly reactive, especially with alkali metals and alkaline earths

Alkaline Earth Metals

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• Two electrons in the outer shell
• Low electron affinities
• Low electronegativities
• Readily form divalent cations.

Metalloids

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• Electronegativities between those of metals and nonmetals
• Ionization energies between those of metals and nonmetals
• Possess some characteristics of metals/some of nonmetals
• Reactivity depends on properties of other elements in reaction
• Often make good semiconductors

How is DNA useful?

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Finding common ancestors for species

Mutations of DNA are used as an evolutionary and molecular clock

Reading Formulas

How many Hydrogens and how many Oxygens would be in

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The

There are 4 hydrogens and 2 oxygens[image]

Polar Bonds between Hydrogen atoms

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Other water facts

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Water dissolves many things including ionic compounds.

The high specific heat of water is the result of strong polar bonds.

Name that Chemical Reaction

A + B --> AB

Synthesis

Two substances combine to form a single new one.

Name That Chemical Reaction

AB --> A + B

Decomposition

One compound is broken down to simpler components

Name That Chemical Reaction

A + BC --> AC + B

Single Replacement Reaction

A metal replaces a metal, or a nonmetal replaces a nonmetal.

Name That Chemical Reaction

AB + XY --> AY + XB

Double Replacement

A metal replaces a metal, and a nonmetal replaces a nonmetal.

acid–base reaction

In a typical acid/base reaction the acid and base react to form a salt and water.

Explain the three types of heat transfer

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Conduction: the direct transfer of heat (kinetic energy)by object touching one another.

Convection: Convection is the transfer of heat energy in a gas or liquid by movement of currents. Warm substance rise and cooler one sink moving the energy around.

Radiation: Electromagnetic waves that directly transport kinetic energy over a distance.

Contrast endothermic and exothermic reactions

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"Endo" means "to draw into," and "Exo" means "to give off."

* Endothermic reactions draw heat in from their surroundings. (cold)

* Exothermic reactions give heat off to their surroundings. (heat)

By increasing the

Temperature:Speed  them up=equals more collisions

Pressure:Push them closer together=more collisions

Concentration: of the substance=more collisions

balance

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cm

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Line

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Bar

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Circle

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Peer reviewed scientific journals

Government or University documents and web sites

Lead

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Which form of radiation particle is a higher risk to humans? Alpha or Beta?

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(Alpha Radiation radiation is a heavy, very short-range particle and is actually an ejected helium nucleus.   Most alpha radiation is not able to penetrate human skin.)

 Beta Radiation is a light, short-range particle,and is actually an ejected electron. Beta radiation may travel several feet in air and is moderately penetrating. Beta radiation can penetrate human skin to the "germinal layer," where new skin cells are produced.

The hydrogen must be packed closely together to

overcome the electrostatic repulsion by the attractive nuclear force which is stronger at close distances.

be made of a material that will not undergo fission and be a good absorber of neutrons

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electron

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A nuclear reaction has occured

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Insect resistant crops

DNA specific cures for individuals

Crime solving

(many others)

Pesticide resistant insects

Antibiotic resistant bacteria

DNA identification of offspring traits resutling in designer babies

Crops that are genetically identical removing the natural protection of variation

What are the requirements for something to be considered a catalyst?

Which types of reaction will increasing the temperature speed up?

A.      Exothermic

B.      Endothermic

C.      Isothermic

Answer: All of them.  Adding energy in the form of heat will raise the energy of the reactants, increasing the number of particles with enough energy to make it over the activation energy hurdle.  The slowest part of any chemical reaction is making it over the big hill, so this has the effect of speeding up the reaction.   A rule of thumb that chemists use is that for every 10 degrees of temperature increase, the reaction rate will double.

How does a catalyst speed up a chemical reaction?

A catalyst provides an alternate reaction pathway with a lower energy of activation.  

Since the energy hurdle is lower, the reactants make it over it faster, speeding up the reaction. 

This effect does not depend on if the reaction is exothermic or endothermic, since it only changes the activation energy, not the energies of the reactants or products.