Physics Chapter 2
Define Compound?
A molecule that contains at least 2 different elements.
What is Dmitiri Mendeleev's Work?
Advanced Doltons work by organizing the known elements into the periodic table which demonstrates that elements arranged in order of increasing atomic mass.
Describe the Neutron?
Another componet of the nucleus, has no electrical charge and a mass of 1.625 X 10^-27kg.
What is John Daltons Theory?
Based on scientific evidence all elements were formed by atoms and compounds were formed by molecules and molecules by fixed ratios of Each type of consistent atoms,resulting in a predictable mass. This theory also recognized that elements combined in definite proportions to form compounds and a chemical reaction was a rearrangement of atoms.
Niels Bohr's work does what?
Brings us to the theory and model of the atom with which we are most familiar with.
Know how each electron shell is lettered?
Each electron shell of an atom is lettered beginning with K nearest to the nucleus and moving outward with L,M,N,O,P and so on.
Define positive Ion?
If the atom loses an electron, the positive charges will out # the negative charges and the atom will have a net positive charge which is called a positive ion.
Which shell has the greatest binding energy?
K- because it is closest to the nucleus
Each atom has a nucleus, what is the nucleus made up of?
Protons and Neutrons
Know the difference between the proton and neutron?
Protons have a positive charge and Neutron is neutral no charge.
what is the modern atomic theory?
States that the atom is the building block of matter and bohr's theory describes the atom as having 3 fundamental components; electrons, neutrons, and protons.
What is Democritus Theory?
The Earliest theory hypothesized that all things were made of tiny, invisible structures called atoms.
What is Joseph John Thomson's discovery?
The electron
Define Atomic Mass Number?
The number of Protons and Neutrons an atom has in its nucleus.
Define Atomic Number?
The number of Protons in an atom's nucleus(remember in a stable atom the # of electrons = the # of protons, so the atomic # indicates the # of electrons too)
Know how the electron shell fills?
These shells fill from the K shell outward
What are the 2 primary ways atoms bond?
To form molecules and subsequently more complex structures with covalent or ionic bonds
Define electron shells?
a defined energy level at a distance from the nucleus within which electrons orbit; this describes a sphere around the nucleus.
Define Binding Energy?
a force of attraction that holds the nucleus of an atom together and holds electrons in orbit around the nucleus.
Define Molecule?
a molecule is formed when 2 or more atoms join together
Where the word atom comes from?
atom comes from the greek word atomos meaning "indivisible" (inseparable, unbreakable)
What is ionic bonding based on?
based on the attraction of opposite charges
What is covalent bonding based on?
based on two atoms "sharing" electrons that then orbit the nucli,aka figure 8
Describe the electron?
electrons have a negative electrical charge and a mass of 9.109 X10^-31 has significant energy and very small..
Know the technical aspect behind a neutral charge atom (what makes it neutral)?
if an atom has equal # of protons and electrons it has no net charge there for making it a neutral atom.
Define Negative Ion?
if atom gains an extra electron the negative charges will out # the positive and the atom will have a net negative charge which is called a negative ion.
Describe the proton?
one component of the nucleus positive electrical charge and a mass of 1.673X 10^-27kg.
What binding energy is a measure of?
the amount of energy necessary to split and atom (break it apart)
Know what happens if the balance of an atom is disrupted?
the atom charge becomes positive if there are more protons or negative if there are more electrons.
Know how many electrons the 1st shell can hold?
the first shell con only hold 2 electrons
Define Valence Shell?
the outermost shell
