Atomic Stucture, Scientists and Average Atomic Mass Test

review notes, labs, practice sheets

Erwin Schrodinger

developed quantum wave equation

James Chadwick

discovered neutrons

Ernest Rutherford

performed the Gold Foil Experiment that showed atoms were made up of mostly empty space and a nucleus in the middle

JJ Thomson

proposed Plum Pudding Model - discovered electrons but was incorrect in their location

Neil Bohr

proposed that electrons were in specific orbits around the nucleus

John Dalton

Dalton Atomic Theory

1. All elements made up of atoms

2. Atoms of a particular element are identical

3. Atoms can’t be created or destroyed

4. Chemical compounds are formed when different kinds of atoms combine

5. Chemical reactions are formed when atoms are rearranged — changes the way atoms are combined but not the atoms themselves

“label” the element

A - atomic number

B - element symbol

C - element name

D - atomic mass

atomic number

the number of protons

atomic mass

number of protons + number of neutrons; average of all atoms of that element in the world

neutral atoms

when the number of protons = number of electrons

ion

when the number of electrons are different than the number of protons

cation

less electrons; more protons

anion

more electrons; less protons

isotope

same number of protons, different number of neutrons

nuclear notation?

A - atomic mass

B - atomic number

C - element symbol

how to calculate average atomic mass?

sum of (% natural abundance)(atomic mass) for all isotopes given

Copper has two isotopes. Copper-63, which has an atomic mass of 62.93 amu and copper-65, which has an atomic mass of 64.93 amu. In any sample of copper atoms, 69.1% will be Copper-63 and 30.9% will be Copper-65. Calculate the average atomic mass of naturally occurring copper.

63.54 amu