Properties
The characteristics of the matter
Matter classified by ____ and ____
State and composition classifies ____
3 states of matter?
Gaseous state, liquid state, and solid state are the 3 states of ____
Physical change
A recognizable difference in the appearance of a substance without causing any change in its composition or identity
Ex-water: snow-rain-humidity
Physical property
Observed or measured without changing the composition or identity of a substance
Chemical properties
Result in change of composition and can be observed only through chemical reactions
Chemical reactions
Chemical substance is converted to one or more different substance by rearranging, removing, replacing, or adding atoms.
Ex: carbon dioxide + water -(light, chlorophyll)-> sugar + oxygen
Chemical change
(Synonymous w/ chemical reaction)
Ex: process of formation of sugar
Intensive property
Property of matter that is independent of the quantity of substance
Extensive property
Depends on the quantity of a substance
Pure substance
Substance with only one component.
Ex- Pure water:made only of particles containing 2 hydrogen atoms and 1 oxygen atom (H2O)
Element
A pure substance that cannot be changed into a simpler form of matter by any chemical reaction
Compound
Substance resulting from the combination of 2 or more elements in a definite, reproducible way
Mixture
Combination of 2 or more pure substances in which each substance retains its own identity.
Ex: alcohol and water can be combined in a mixture.
They coexist as pure substances because they do not undergo a chemical reaction.
Mixture may be homogeneous or heterogeneous.
Homogeneous mixture
Mixture with uniform composition, its particles are well mixed, or thoroughly intermingled.
Ex: Alcohol and water is described as a solution.
Heterogeneous mixture
Mixture with nonuniform composition.
Ex: Salt and pepper
Atom
Basic structural of an element, which is the smallest unit of an element that retains the chemical properties of that element.
Made of proton, neutron, and electron.
Nucleus of atom
Small, dense, positively charged region in the center of the atom.
Composed of positively charged protons and uncharged neutrons.
Protons (p+)
Positive charge, in atom's nucleus.
Neutron (n)
Uncharged, in atom's neucleus
Electron (e-)
Negative charged, surrounding the nucleus.
Low mass compared to protons and neutrons.
Atomic number (Z)
Equal to the number of protons in the atom
Mass number (A)
Equal to the sum of the number of protons and neutrons
Notations of atom?
AZXE
A- mass number: # of protons & neutrons
Z- atomic number: # of protons
X- place for atom name
E- place for charge (+/-)
Isotopes
Atoms of the same element having different masses because they contain different number of neutrons. (Have different mass numbers)
Ex: carbon-12 (C-12), carbon-14 (C-14)
Atomic Mass
The weighted average of the masses of each isotope that makes up the element.
Measured in atomic mass unit (amu)
1 amu = 1.66 x10-24 grams (g)
Dalton's Atomic Theory
All matter consists of tiny particles called atoms
An atom cannot be created, divided, destroyed, or converted to any other type of atom.
Atoms of a particular element have identical properties
Atoms of different elements have different properties
Atoms of different elements combine in simple whole-number ratios to produce compounds (stable combination of atoms)
Chemical change involves joining, separating, or rearranging atoms
Ions
Electrically charged particles resulting from gain or loss of electrons by an atom
Anion
Result of parent atom gaining one or more electrons
Ex 8035Br-: Bromine-80 gains an electron
Cation
Result when parent atom lose one or more electrons
Ex: 3919K+: Potassium-39 loses an electron
Quantum level
Energy level: Orbit level an electron is at, thus fix energy at fix level
Only allowed location for electrons
Quantization
Concept of fix energy and fix levels
Absorb energy: closer neutron move farther from nucleus
Release energy: farther neutron move closer to nucleus
Quantum number
Orbit identification number (n)
Bhor Model
1st step to understanding an atom
Electrons exist in specific energy states, transition requires specific amount of energy
Quantum Mechanics
Schroedinger's theory.
Each level has sub level, which also has one or more atomic orbitals
Principal energy levels
Designated as n= 1,2,3,...
2(n)2
ex: n=1, 2(1)2= 2, 2 electrons
Sublevel
____is a set of energy-equal atomic orbitals within a principal energy level.
Symbols in order: s<p<d<f
1st principal energy level (n=1) has 1 possible levels: 1s
2nd principal energy level (n=2) has 2 possible levels: 2s and 2p
....
4th principal energy level (n=4) has 4 possible levels: 4s, 4p, 4d, 4f
Aufbau Principle
Electron fill the lowest-energy orbital available first
Energy configuration
The arrangement of electrons in atomic orbitals
Shorthand Electron configuration
Bismuth
Noble gas in bracket: Tin (Sn)1s22s22p63s23p64s23d104p65s24d105p2 krypton; [Kr]5s24d105p2 as shorthand configuration for tin, since [Kr]1s22s22p63s23p64s23d104p6
Highlight valence electrons