Please enable JavaScript.
Coggle requires JavaScript to display documents.
Ashwin Chandra's First Semester Coggle (Periodic Trends (MAIN TRENDS…
Ashwin Chandra's First Semester Coggle
Bonding
Covalent Bonding
Octet Rule:The octet rule is a chemical rule of thumb that reflects the observation that elements tend to bond in such a way that each atom has eight electrons in its valence shell, giving it the same electronic configuration as a noble gas
The HONC rule: A rule that states that in most molecules, H makes 1 bond, O makes 2 bonds, N makes 3 bonds, and C makes 4 bonds.
Polar Covalent Bonds
Electrons aren't shared equally
Nonpolar covalent bonds
Electrons are shared equally
Ionic Bonds
Metallic Bonds
AXE
A:Central Atom
X: Bonded electrons
E: Lone pairs
The sum of E and X is the steric number
Chemical Reactions
Intermolecular forces
The forces which mediate interaction between molecules, including forces of attraction or repulsion which act between molecules and other types of neighboring particles
IMF Trends: The stronger the attraction between molecules, the more energy it will take to seperate them
Balancing Equations:
Reaction types
Synthesis
A+B -> AB
Double Replacement
AX+BY -> AY+BX or AB + XY
Decomposition
AB-> A+B
Single Replacement
AX+B -> AB+X or BX+ A
Combustion equations
AB -> H2O + CO2
Periodic Trends
The shielding effect describes the balance between the pull of the protons on valence electrons and the repulsion forces from inner electrons, The effective nuclear charge is the net positive charge experienced by valence electrons.
The electron affinity of an atom or molecule is defined as the amount of energy released or spent when an electron is added to a neutral atom or molecule in the gaseous state to form a negative ion.
Electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself. An atom's electronegativity is affected by both its atomic number and the distance at which its valence electrons reside from the charged nucleus.
Ionization energy is significantly smaller down a group
The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding shells of electrons.
Ionic Radii
Anion- a negatively charged ion, i.e. one that would be attracted to the anode in electrolysis.
Cation- a positively charged ion, i.e. one that would be attracted to the cathode in electrolysis.
MAIN TRENDS
Ionization Energy
Electronegativity
Atomic Radius
Electron Affinity
Atomic Structure
Dalton's atomic theory proposed that all matter was composed of atoms, indivisible and indestructible building blocks. While all atoms of an element were identical, different elements had atoms of differing size and mass.
The modern atomic theory states that all matter is composed of atoms. Atoms themselves are composed of protons, neutrons, and electrons. Each element has its own atomic number, which is equal to the number of protons in its nucleus.
In 1897, J.J. Thomson discovered the electron by experimenting with a Crookes, or cathode ray, tube. He demonstrated that cathode rays were negatively charged. Thomson realized that the accepted model of an atom did not account for negatively or positively charged particles.
What makes up an Atom?
Proton:a stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron, but of opposite sign.
Neutron:a subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.
Electron: a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.
Nuclear/Radioactive Decay
Alpha Decay*
Beta Decay
Gamma Decay
Equation
Half-life:the time taken for the radioactivity of a specified isotope to fall to half its original value
Nuclear Chemistry:the subfield of chemistry dealing with radioactivity, nuclear processes, and transformations in the nuclei of atoms, such as nuclear transmutation and nuclear properties.
Electrons
.
Orbitals are regions within an atom that the electron will most likely occupy. Each subshell has a specific number of orbitals: s = 1 orbital, p = 3 orbitals, d = 5 orbitals, and f = 7 orbitals. One orbital can contain a maximum number of two electrons.
Electron Configuration rules
The aufbau principle, from the German Aufbauprinzip (building-up principle), also called the aufbau rule, states that in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels.
Hund's rule of maximum multiplicity is a rule based on observation of atomic spectra, which is used to predict the ground state of an atom or molecule with one or more open electronic shells.
The Pauli exclusion principle is the quantum mechanical principle which states that two or more identical fermions cannot occupy the same quantum state within a quantum system simultaneously.
ORBITAL ORDER
Definitions
Spetra
a band of colors, as seen in a rainbow, produced by separation of the components of light by their different degrees of refraction according to wavelength.
Electron
a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.
Orbital
relating to an orbit or orbits.
:
