FINAL STUDY GUIDE-101

1 kilogram =

2.2 pounds

Fundamental units

Base ( basic) units from which others are built

Quarks in the nucleus are held together by

Gluons, gluons act as mediators of the storing nuclear force which flow between all the protons and the neutrons to hold the nucleus together

Energy

Kgm^2/s^2 is a unit called joules (J)

The ionization of an atom by an x-ray results in the creation

Of an ion pair , one negative and one positive

The ionized atom may form an ionic bond with an atom of

Opposite charge

Derived units

Special units that are a combination of the base units

Lenght

Unit of lenght in SI units is the meter

Electrical energy

Utilizes the movement of electrons through the application of an electric potential difference ( voltage)

Radioactivity might be considered as a measure of the substance's current effectiveness in

emitting radiation, whereas the radioactive half-life might be thought of as a measure of the substance's long-term effectiveness over time.

Matter

- Anything that occupies space - fundamental building block of matter is the atom - all matter has mass - matter can exist in many forms but the quantity of matter ( mass) is maintained through transformations

There are two major ways in which atoms combine

- Covalent Bonding - Ionic Bonding

Ionization

- acquisition or loss of an electron by an atom is termed ionization

Niels Bohr

- applied Quantum Theory to the Rutherford model - electrons travel in stationary orbits around the nucleus - led to calculation of possible energy levels for these orbits - light is emitted when an electron moves into a lower energy unit

Dmitri Mendeleev

- arranged the 63 known elements into a periodic table based on atomic mass and similarity of properties

John Dolton

- atoms of different elements could be distinguished by their weight - all matter composed of atoms - atoms cannot be made or destroyed - all atoms of the same element are identical - different elements have different types of atoms - chemical reactions occur when atoms are rearranged Compounds are formed from atoms of the constituent elements

Bonding

- certain elements can be brought together chemically to form molecules - different molecules may come together to form compounds - a molecule is the smallest recognizable particle of any compound ' - there are many different types of molecules and compounds in our body, through there are relatively few elements - 80% of our body is water, and 95% of our body is composed of four elements , They are ; Nitrogen, Hydrogen, Carbon, Oxygen - compounds may have very different chemical and physical properties than the elements that make them up.

Periodic table elements structure

- column ( group) numbers indicate the number of electrons in the outermost shoe of an element - group number increases by 1 as we move from left to right on the table - since octet rule, after group 8 we must start a new shell around atom - period ( number) on the periodic table of elements equals the number of the outermost electron shell of the element . 1=K, 2=L..... - from period 4 down we see block of columns in the middle of the table called "transitional" elements

Ernest Rutherford

- developed an atomic model with a positive nucleus surrounded by negative orbiting electrons - most of the atom was empty space, and most was contained within the nucleus

Organization elements within the table

- elements in the same groups have the same number of valance electrons ( electrons in their outermost shell ) - elements with similar valance numbers have similar physical properties and react similarly chemically - Groups 1 and 11, are light metals ( except hydrogen, which is a gas). Group 1 are called "alkali metals" - between Group 11 and 111 are the transitional metals - Groups 111 and V11 are "non-metals" - Group V11 are "halogens" - Group V111 contains inert (noble) gases

Force- Newton's Second Law

- force is equal to the product of the mass and acceleration of an object - mathematically described as - F=ma - Derived unit for acceleration is kgm/s^2 called a Newton (N) - weight can be though of as the force of an object due to gravity, mathematically this is described as Wt= mg - also expressed in the derived unit , N

Ionic bonding

- ion is any electrically charged particle - possible for an atom to acquire, from a chemical interaction with another atom, an extra electron in its shells such that the total number of electrons outnumbers the sum of the protons in the nucleus, such an atom will have net charge minus 1 - also possible for an atom to lose an electron through chemical processes or by some types of radiation, including interactions with x-rats, such an atom with a net electrical charge of plus 1, is considered a positive ion -atoms with an opposite charge will be strongly drawn toward opposite ions, and may form an ionic bond - ionic bonding is very strong much stronger than covalent bonding

Electron and shell designations

- number of electrons an atom possesses is equal to the number of proteins in a nucleus - up to seven orbits (Shells) are arranged in concentric circles at different distances to the nucleus - the shells are frequently labeled alphabetically with "K" for the first shell, "L" for the second shell, and so on to the letter Q for the seventh shell - shells also representative of different electron binding energies0 the closer the shell to the nucleus, the higher the binding energy ( K shell always the highest) - binding energy of all electrons is any given shell is greater in larger and more complex atoms than in smaller, simpler atoms

Covalent bonding

- orbitals associated with the electron shells - each orbital can contain two and only two electrons, the reason us related to magnetism - each orbital represents a pair of vacancies in which electrons may reside - when there is an even number of electrons in the outermost shell , there must be an orbital which contains only one electron within its pair of vacancies - occurs between two atoms with an odd number of electrons - unpaired electrons are shared - mist common form of chemical bonding Between atoms

Electromagnetic energy

- travels through space ( radiating) at the speed of light - electrically neutral and has no mass Only difference among the different forms of EM photons is their energy

Electron must be arranged according to the two specific rules :

1. Maximum number of electrons, which can occupy a shell under any conditions is equal to 2N^2, where N is the shell number 2. Outermost shell of an atom can never hold more than 8 electrons, This "octet rule" overrides rule #1 - chemical behavior of an atom is determined only by the number and configuration of electrons in the outermost shell - by the octet rule, outermost shell is considered filled when there are 8 electrons in it - Neutral atoms with exactly 8 electrons in the outermost shell have no tendency at all to connect with other atoms, They are said to be clearly inert

1 inch=

2.54 centimeter

1 meter =

3.3 feet

Electromagnetic energy

A type of energy that consists of tiny bundles of energy called photons or quanta

Electromagnetic energy that processes a great deal of energy has the ability to remove

An orbital electron from an atom- an interaction called IONIZATION

Number of protons in an atom is called

Atomic number

Standard units

Basic units in any particular system of measurement ( traditional British system or the system international

Newton's First Law ( inertia)

Body at rest will remain at rest and a body is motion will remain in motion at a constant velocity- UNLESS they are acted on by an external force

Acceleration

Change in speed in a straight line with respect to time Mathematically - v ( final) - v( initial) / time Might be positive ( object speeding up), negative ( object slowing down) or zero ( object is moving at a constant speed) Derived unit is- m/s^2

All of the Kroger particles comprising the atomic nucleus are

Collectively referred to as nucleons -include protons and neutrons

Sir Joseph JohnThomson

Discovered the electron - established an atomic model in which electrons were embedded within a uniform sphere of positively charged matter ( The plum pudding Model)

Besides changing forms from one type of energy to another, energy can also be converted into mass and vice versa, this is expressed in equation..

E=mc^2 E= energy M= mass in kg C= speed light constant

Isotopes

Each element can be found in different forms based on altering the number of neutrons present. These variations are called the isotopes of each element.

The excess energy will be emitted in the form of radiation; either particulate or

Electromagnetic energy

As a form of electromagnetic energy x-ray is a wave that has no mass or weight, it does however, pocess an incredible amount of

Energy

Potential energy

Energy a body possesses based strictly on its position or its temporary deformed state , potential energy of an object can be expresssed as follows : PE= mgh

Kinetic energy

Energy of motion, kinetic energy of an object can be expressed as follows : KE= 1/2 mv^2 KE= kinetic energy M= mass kg V= velocity in m/s

Chemical energy

Energy released by a chemical reaction

Nuclear energy

Energy that is contained within the nucleus of an atom

Newton's Third Law ( Action/ Reaction)

For every action there is an equal and opposite reaction

Matter and energy

From a physics standpoint everything in the universe can be classified as either matter or energy

It may also emit excess energy in the form of an electromagnetic wave, such as a __________

Gamma ray

The energy of the x-ray is deposited into the electron which then,

Has too much energy to remain in its orbit or shell

Shorthand format for A

In shorthand format, the abbreviation for the element (from the periodic table) is written with the A number (atomic mass) in superscript. This A number may appear either in front of or behind the element symbol, but is always in superscript.

Shorthand format for Z

In shorthand format, the atomic number Z is always written in front of the element in subscript.

When an atomic nucleus becomes unstable, it is spending too much energy trying to keep the nucleons together.

It is in a "hyper" state, and its tendency is to get rid of the excess energy.

The electron may be acquired by another positively- charged atom, neutralizing

It's charge and thereby breaking its bond with another atom

Heat

Kinetic energy of a system on a molecular level Calorie

Atomic number is abbreviated by

Letter Z

Nucleons are

Made of quarks , elementary particles that are the building blocks of all matter

Temperature

Measure of the average energy of motion of the molecules of matter Kelvin (K), thought Celsius and Fahrenheit are much more popular

Time

Measure of the duration of events, it is measured by the seconds ...questionable this one wasn't sure

Newton's third law

Momentum - the quantity of motion that an object has - momentum is conserved through any interactions - mathematically described as p=mv Derived unit for momentum is the kg m/s Work - a force acting upon an object for a distance - mathematically this is described as W= Fd - the derived unit for work is the Joule (J) Power - the rate of doing work - mathematically this is described as P=W/= Fd/t - derived unit for power is the Watt (W)

Unit

Quantity adopted as a standard of measurement by which other quantities of the same kind can be measured

Mass

Quantity of matter contained in any physical object, does not consider differences in gravitational pull as weight does, unit os mass is the kilogram

Velocity ( distance over time)

Rate of change of an objects position in a given direction with time Mathematically described as- v=d/t Derived unit is - m/s

If one of its electrons acquires extra energy, it cannot

Remain in that shell or orbit

If the atomic mass and atomic number are known ( from periodic table) , we can find the neutron number by

Subtracting the atomic number from the atomic mass, according to the formula A-Z= N

Conversions from one system to another

Temperature Celsius= 5/9 ( temperature Fahrenheit-32) Temperature Fahrenheit= 9/5 temperature Celsius + 32 Temperature kelvin = temperature Celsius + 273

The half-life is a characteristic of the particular radioisotope.

That is, each radionuclide has a distinct half-life different from other radioactive elements.

Brief history of the atom

The Ancient Greeks- "atom" meaning "indivisible" A=without (not) and temon=cut Four substances of matter from which all was made; Earth, water, air, and fire

Radioactivity

The ________________________________________ of a particular substance is the rate at which it is decaying, usually measured as the number of decay events per second.

New chemical compounds form, which can be

The basis for disease such as cancer

Thermal energy ( heat)

The energy of kinetic energy or motion at the molecular level, three ways in which the flow of thermal energy may occur : - radiation - any time energy is emitted and transferred through space - Conduction- occurs when a hot object or substance comes into direct contact with a cooler one - ( two types ) - Convection- refers simply to stirring hot molecules into cooler ones though the mixing of fluids or air

One- half

The half-life of a particular radionuclide (radioactive element) is defined as the time required for the rate of its radioactivity to decrease to _________________-____________________________ of the original.

Density

The mass per unit volume of a substance- kg/m^3

Volume

The measure of a capacity of a container - m^3

Area

The measure of a given flat ( two dimensional) surface - m^2

Atomic mass

The sum total of protons plus neutrons (the number of all nucleons) is the atomic mass, abbreviated

Conduction types

Thermal conductors- materials that radiate or conduct heat energy well Thermal insulator- materials that do not radiate heat energy well

A specific shell or orbit around the nucleus of an atom is synonymous

With a certain energy level

Radioactive nucleus

an unstable nucleus that undergoes radioactive decay

We define a radionuclide as

any atom which is radioactive.

It is possible for an atom to have too few or too many neutrons in its nucleus. If this is the case, the nucleus.

becomes unstable

Unlike radioactivity, which decreases over time, the half-life is absolutely

constant for a particular radionuclide.

Nuclear fission

described the "splitting" of atomic nuclei into smaller fragments

If it emits a particle, it loses mass, so it no longer has so much "weight" to hold together. But remember that mass and energy are interchangeable, so losing mass is

equivalent to losing energy.

As we progress up the periodic table, the ratio of neutrons to protons increases

exponentially as the elements get heavier and heavier.

This stable configuration puts the nucleus at its lowest possible energy state This is called its

ground state, and all nuclei seek out that lowest energy state.

Atomic weight

is slightly different than atomic mass; the atomic weight is an average of relative isotopic masses for a given element from different sources. Standard atomic weights are subject to natural variation, and are rarely a whole number.

Nuclear fusion

is the forcing together of two smaller nuclei to form a single, larger nucleus.

Radioisotopes disintegrate into stable isotopes

of different elements at a decreasing rate so that the quantity of radioactivity never quite reaches zero.

Both processes, fission and fusion,

result in the release of large amounts of energy that can be used for power.

For each particular element (# of protons) there is an "ideal" number of neutrons to have in the nucleus which

results in the most stable configuration.

There are two aspects of an unstable substance that make it more dangerous (or more effective);

these are its decay rate (radioactivity) and its radioactive half-life.