General Chemistry Unit #4 Flashcards
Polyatomic Ion
- an ion composed of more than one atom
- composed of multiple covalently bonded atoms
Molecular vs Ionic
A “molecular” compound is formed when atoms share electrons through covalent bonds, typically between non-metals, while an “ionic” compound is formed when electrons are transferred between atoms, usually between a metal and a non-metal, creating positively and negatively charged ions that are attracted to each other
Molecular
relating to or consisting of molecules.
Ionic
type of linkage formed from the electrostatic attraction between oppositely charged ions in a chemical compound
Covalent Bonding
creating bonds with other atoms
Ionization
Gain or lose electrons (ion)
Compound
Two or more atoms joined together by a strong force (bond)
Covalent
Sharing of electrons
Ionic
Attraction of charged ions
Isoelectric
Two atoms, ions, or molecules that have the same electronic structure and same number of valence electrons (“equal electric charge”)
Solution
Mixture of a solute dissolved in a solvent
Homogeneous
Uniform, dissolved solution
Heterogeneous
(precipitate) The solute is visible, not dissolved solution
Concentration
The ratio of solute to solvent
Concentrated
more solute in the solution
Dilute
Less solute in solution
Dilution
Decreasing the concentration of a solution
VSEPR (Valence Shell Electron Pair Repulsion Theory)
electron pairs around a central atom will arrange themselves as far apart as possible to minimize repulsion, resulting in a specific molecular shape like linear, trigonal planar, tetrahedral, or bent.
Linear
a molecular structure where atoms are arranged in a straight line, with a bond angle of 180 degrees between them
Bent
a molecular shape where the central atom has two bonded atoms and two lone pairs of electrons, resulting in a V-shaped or angular arrangement,
Trigonal Planar
a molecule where a central atom is bonded to three other atoms, arranged in a flat plane around the central atom, forming a triangular shape with bond angles of 120 degrees between each atom
Tetrahedral
a molecule where a central atom is surrounded by four substituents, positioned at the corners of a tetrahedron, resulting in bond angles of approximately 109.5 degrees between each substituent
Dipole-Dipole
an attractive force that occurs between polar molecules, where the partially positive end of one molecule is attracted to the partially negative end of another molecule
London dispersion
the weakest type of intermolecular force that occurs between all molecules, arising from temporary fluctuations in electron distribution, creating momentary positive and negative poles that attract nearby molecules
Strong Acid
Completely dissociates in water - only ions remain
Weak Acid
Partially dissociates (ionizes)
Non polar covalent bond
No difference in electronegativity
Polar covalent bond
Difference in electronegativity
Polar molecular requirements
1) Contains polar bonds
2) Uneven e- sharing for whole molecule (molecular dipole) -sum of bonds
Determining steps of a polar molecule
1) Lewis Dot Structure (2D)
2) Molecular Structure (3D)
3) Identify Polar Bonds
4) Find (if there) molecular dipole
Hydrophobic
Water-fearing (nonpolar)
Hydrophilic
Water-loving (polar)
Phospholipids
Bilayers based hydrophobicity “like attracts like”
Hydrogen bonding
Interaction of partial positive [(S+) on H] [Donor] and [partial negative charge (S-) on O, N, F] [Acceptor]
