Chap. 2 (Vocab) Flashcards
Compound
Atoms joined by bond; substance of 2 or more different elements combined
Matter
Anything that takes up space + has mass
Elements
Any substance that cannot be broken down into any other substance
Essential Elements
Chemical element required for an organism to survive, grow, and reproduce
Trace Elements
Indispensable element for life but required in extremely minimum amounts
Atom
Smallest unit of matter (properties of elements)
Subatomic Particle
Particles in an atom that form its structure
Proton
A single positive charge
Electron
A single negative charge
Atomic Nucleus
An atom’s central core made of protons and neutrons
Neutron
No electrical charge
Dalton
Measure of mass for atom and subatomic particles (atomic mass/ AMU)
Atomic Number
Number of protons in the nucleus of an atom
Mass Number
Total number of protons + neutrons in nucleus of atom
Isotopes
element with = number of protons and different numbers of neutrons
Radioactive Isotope
Isotope that is unstable, nucleus decays and gives off energy
Half-life
Amount of time it takes 50% of a radioactive isotope to decay
Radiometric Dating
Method to determine age of rocks/fossils based on half-life of R. Isotopes
Energy
Capacity to cause change
Potential Energy
Energy stored with potential to be released
Kinetic Energy
Energy in motion and being used for movement
Electron shell
Energy level of electrons at an average distance from the nucleus of an atom
Valence Electrons
Electron in outermost electron shell
Valence Shell
Outermost energy shell of atom
Orbital
3D approximation of where electron is found in valence shell
Chemical Bonds
Attraction between 2 atoms
Covelant Bonds
Strong chemical bond where atoms share PAIRS of valence electrons
Single Bond
Single covalent bond; sharing pair of valence electrons by 2 atoms
Lewis Dot Structure
Electron distribution of electron sharing; DOts represent valence electrons
Structural Formula
Line represents pair of shared valence electrons
Double Bond
Double covalent bond; sharing of 2 pairs of valence electrons by 2 atoms
Electronegativity
2 atoms participating in a covalent bond; The more elect. an atom the stronger it pulls electrons
Nonpolar Covalent Bond
Electrons are shared equally between 2 atoms of similar electroneg.
Polar Covalent Bond
Electrons are shared unequally between atoms/ diff. electroneg. ; SHared electron is pulled closer to the more electneg.
Ions
Group/atom that has gained or loss 1 or more electrons
Cation
Positively charged ion
Anion
Negatively charged ion
Ionic Bond
Attraction between 2 oppositely charged ions= Chemical Bond
++-=x
Ionic Compound (Salts)
Compound resulting from formation of an ionic bond
Hydrogen Bond
Weak chemical bond formed when positive hydro. atom of a Polar CB. in one molecule is attracted to a negative atom of a Polar CB in another molecule
Von Der Woals Interactions
Weak interactions between molecules (when atoms + molecules are close together)
Chemical Reactions
Making/ Breaking of chemical bonds bonds, leading to change in composition of matter
Chemical Equilibrium
In chemical reaction, state where rate of forward reaction = rate of reverse reaction
Equilibrium
Products and reactant concentrations have stabilized at a ratio (ex. Decomposes as fast as it forms.)
Valence
Covalent bonding capacity between atoms
