Presentation on theme: "Ch. 17 – Properies of Atoms and Atomic Structure I. Structure of the Atom Symbols Subatomic particles Electron cloud model."— Presentation transcript:
Ch. 17 – Properies of Atoms and Atomic Structure I. Structure of the Atom Symbols Subatomic particles Electron cloud model
A. Chemical Symbols Capitals matter! Element symbols contain ONE capital letter followed by lowercase letter(s) if necessary. Co vs. CO Metal that forms bright blue solid compounds. Poisonous gas.
B. Subatomic Particles Most of the atom’s mass. Atomic Number equals the # of... in a neutral atom NUCLEUS ELECTRONS PROTONS NEUTRONS NEGATIVE CHARGE POSITIVE CHARGE NEUTRAL CHARGE ATOM
B. Subatomic Particles Quarks 6 types 3 quarks = 1 proton or 1 neutron He
A. Orbital Region where there is 90% probability of finding an electron. Can’t pinpoint the location of an electron. Density of dots represents degree of probability.
B. Energy Levels Electrons can only exist at certain energy levels. Low energy levels are close to the nucleus. Each energy level (n) can hold 2n 2 electrons.
C. Bohr Model Diagrams Simplified energy levels using Bohr’s idea of circular orbits. e- Maximum e - Level 12e - Level 28e - Level 318e - Level 432e - Lithium Atomic #:3 Mass: 7 # of p:3 # of e:3 # of n:4 p p n n n n p e- Can replace with: 3p 4n
C. Bohr Model Activity Choose a number between 1 & 18. Find your element by the atomic number you picked. Draw a Bohr Model diagram for your element. Round off the mass listed on the table and subtract the atomic # to find the # of neutrons. Abbreviate the # of ‘p’ and ‘n’ in the nucleus. Have a partner check your drawing. Repeat with a new element.
II. Masses of Atoms Atomic Mass Mass Number Isotopes