Defining the Atom: Mr. Smith's Section 4 Coggle (Determining an Atom…
Defining the Atom: Mr. Smith's Section 4 Coggle
The smallest particle of an element that retains its identity in a chemical reaction.
Believed that atoms were indivisible and indestructible.
Among the first to suggest existence of atoms.
Dalton's Atomic Theory
Atoms of the same element are identical. The atoms of any one element are different from those of any other element.
Atoms of different elements can physically mix together or can chemically combine in simple whole-number ratios to form compounds.
All elements are com posed of tiny indivisible particles called atoms.
Chemical reactions occur when atoms are separated, joined, or rearranged. Atoms of one element, however, are never changed into atoms of another element as a result of a chemical reaction.
Most Radii of Atoms fall between 5x10^-11 m and 2x10^-10 m
Discovered in 1932
Mass equal to the proton
Discovered in 1897
Physicist J. J. Thomson
Smallest part of the Atom
Discovered in 1886
Large Particle (1840x the mass of electron.)
Number of protons determines the atomic number of an atom.
In the nuclear atom, the protons and neutrons are located in the nucleus.
The electrons are distributed around the nucleus and occupy almost all the volume of the atom.
Determining an Atom
elements are different because then contain different numbers of protons.
determined by the number of protons in the nucleus of an atom of that element.
In a neutral atom, the atomic number = the # of protons and # of electrons.
the Total number of protons and neutrons in an atom.
Number of Neutrons = Mass Number - Atomic Number
Atoms with the same number of protons, but different numbers of neutrons.
10 protons, 10 Neutrons, 10 Electrons
10 protons, 11 Neutrons, 10 Electrons
10 protons, 12 Neutrons, 10 Electrons
Weighted average mass of the atoms in a naturally occurring sample of the element
Periodic Table of Elements
Ordered and arranged by the number of protons in the nucleus, aka. THE ATOMIC NUMBER
Have similar chemical and physical properties.