Atomic Structure and Atomic Structure and ModellingModelling

General StructureGeneral Structure

central nucleus containing protons and central nucleus containing protons and neutrons, tightly packedneutrons, tightly packed

fast moving electrons move around nucleus in fast moving electrons move around nucleus in a clouda cloud

sizesize of an atom (radius) depends on size of of an atom (radius) depends on size of ____________________________

massmass of the atom is concentrated in the of the atom is concentrated in the __________________

General StructureGeneral Structure

History of Atomic ModelsHistory of Atomic Models1.1. ___________ (400 B.C.)___________ (400 B.C.)

- Greek philosopherGreek philosopher

- thought matter was made up of smaller thought matter was made up of smaller particles he called ______particles he called ______

Atomic TheoryAtomic Theory

2.2. ___________ (1766-1844) ___________ (1766-1844)- English chemistry teacher who studied the English chemistry teacher who studied the

ratios of elements in chemical reactionsratios of elements in chemical reactions- developed a theory about atomsdeveloped a theory about atoms

Dalton’s Atomic TheoryDalton’s Atomic Theory

1.1. All matter consists of _______.All matter consists of _______.- atoms of an element cannot be cut smaller and cannot be created atoms of an element cannot be cut smaller and cannot be created

or destroyedor destroyed

2.2. All the ______ of one element are ________ in All the ______ of one element are ________ in mass and other properties and are ________ mass and other properties and are ________ from atoms of any other element.from atoms of any other element.

- Ex. all oxygen atoms have same mass and properties which are Ex. all oxygen atoms have same mass and properties which are different than any other elementdifferent than any other element

3.3. Atoms of one element cannot be __________ Atoms of one element cannot be __________ into atoms of another element.into atoms of another element.

Dalton’s Atomic Theory cont’dDalton’s Atomic Theory cont’d4.4. Compounds are the chemical combination Compounds are the chemical combination

of two or more elements in a __________. of two or more elements in a __________. - Ex. the compound water (H- Ex. the compound water (H22O) always has a ratio of hydrogen to O) always has a ratio of hydrogen to

oxygen that is 2:1 (2 H for every 1 O)oxygen that is 2:1 (2 H for every 1 O)

Was Dalton correct??Was Dalton correct??Were any points of hisWere any points of histheory wrong??theory wrong??

Developing Atomic ModelsDeveloping Atomic Models

3.3. _____________ (1856-1940) _____________ (1856-1940)

- English physicist who discovered the English physicist who discovered the electronelectron

- proposed ___________ model, postively proposed ___________ model, postively charged mass with electrons distributed charged mass with electrons distributed all overall over

More ModelsMore Models

4.4. ______________ (1871-1937) ______________ (1871-1937)- English scientistEnglish scientist- proved that atom is mostly _____________ with mass proved that atom is mostly _____________ with mass

concentrated in small, central, positively charged middle concentrated in small, central, positively charged middle (__________)(__________)

More ModelsMore Models

5.5. ____________ (1885-1962)____________ (1885-1962)- Danish physicistDanish physicist- thought that electrons move around nucleus in ______ thought that electrons move around nucleus in ______

__________ (like planets orbiting the sun)__________ (like planets orbiting the sun)- paths (or orbits) farther away from the nucleus have paths (or orbits) farther away from the nucleus have

________________________________________

Dalton (1807) Thomson (1897)

             

  - Cannot be broken into smaller pieces - Solid - Small

                

- Raisin bun model - Positive mass with electrons embedded - Neutral atom

Rutherford (1911) Bohr (1885)

- Nuclease w/ protons - “Empty space w/ electrons” -Planetary model

                      

                    

                    

- Protons/neutrons in the middle (nucleus)- Electrons in energy levels orbits around nucleus