Untitled Flashcards Set

Science Notes

A. Pure substances - Has a definite Composition

1. Elements - Composed of only one type of atom

2. Compounds - composed of two or more elements held together by a chemical bond

B. Mixtures - variable composition

1. Homogeneous - A type of mixture that has only one phase. known as solution.

2. Heterogeneous - A type of Mixture that has two or more phases.

PHASES OF MATTER

1. Solid

- shape and the volume are fixed.

- small space between atoms and molecules

- difficult to compress

2. Liquid

- has a definite volume

- assumes shape of the container

- relatively farther apart molecules

- molecules move freely and low

- medium compression

3. Gas

- no definite shape and volume

- can be compressed easily.

- Far distance for molecule

PROPERTIES IN MATTER

A. Physical - properties of matter that can be observed without changing its composition.

1, Intrinsic property - properties of matter that does not depend on amount of matter.

- Density, melting point. boiling pointing

2. Extrinsic property - properties of matter that depend on the amount of matter

- Mass and length

B. Chemical change - properties of matter that can be observed when a chemical reaction occurs.

- undergo corrosion and combustion

CHANGES IN MATTER

A. Physical change - does not change its composition or chemical properties

B. Chemical change - Changes its composition of matter thereby producing new compounds that has a new set of properties

Element - fundamental unit of matter composed of only one type of atom

Atom - Is the basic unit of an element. deprived from Greek word "Atomos"

SUBATOMIC PARTICLE

A. Proton - positively charged particle.

B. Electron - Negatively charged particle

Atomic number of an atom - total number of protons in an atom

Mass number of an atom - total number of protons and neutrons

nuclear symbol - represents the symbol of the element with its atomic number or mass number.

Cation - positively charged species that is formed by the loss of electrons. (+n)

Anion - is a negatively charged particle that is formed when an neutral atom gains electrons (-n)

(n) - represents electrons gained.

Isotopes - are atoms of the same element that differs in the number of electrons.

ELECTRON CONFIGURATION

Aufbau principle - Describes the order in which the electrons fill the orbitals in an atom

Valence electrons - Are the electrons found in the outermost energy level.

Order - 1s - 2s - 2p - 3s - 3p - 4s -3d -4p - 5s - 4d - 5p - 6s - 4f - 5d - 6p - 7s - 5f - 6d

S - 2

P - 6

D - 10

F - 14

RENDS IN THE PERIODIC TABLE

atomic radius - defined as one half the distance from the nuclei of two atoms of the same element

effective nuclear charge - nuclear charge felt by valence electrons

Electron affinity - is the amount of energy released when an electron is added to gaseous atom

Electro negativity - Tendency of an atom to attract electrons

ionization energy - minimum amount of energy required to remove an electron.

orbital diagram - Electron orbital diagrams are diagrams used to show the energy of electrons within the sublevels of an atom or atoms when used in bonding

- two or one arrow in a box

GAS LAWS

CHARLE'S LAW - gives the relationship between volume and temperature if the pressure and the amount of gas are held constant

- Directly proportional

- T1,V1 = T2,V2

BOYLE'S LAW - states that the pressure and volume of a gas are inversely proportional,

- Inversely proportional

- P1,V1 = P2,V2

​GAY LUSSACS LAW - Gay-Lussac’s Law states that the pressure of a gas is directly proportional to its absolute temperature (Kelvin)

- Directly proportional

- P1/T1 = P2/T2