Chem Chapter 2 Study Cards Flashcards
1808
Dalton proposed the atomic theory of matter
1897
Thomson described the atom by using the “raisin bun model”
1922
Bohr proposed that electrons orbit the nucleus in shells
1935
Chadwick discovered that the nucleus contains protons and neutrons
4 atom diagrams
Thomson, nagota, bohr and quantum
Family 1-18
Each vertical column, have very similar chemical properties and characterisctics
Period 1-7
Each horizontal row on the table
Mass number
represents the sum of the number of protons and neutrons in an atom
Atomic number
Shows how many protons are in the nucleus of one atom
How to calculate for neutrons
Mass number - atomic number= neutrons
Metals
shiny, malleable and ductile
Non-metals
solid or gas and are dull,brittle insulators
Metalloids
both non mateallic and metallic properties
Alkali metals
most reactive metals
Alkaline-earth metals
reactive but not as reactive as alkali metals