Science: Atomic Theory & Structure

What did Democritus state?

1) All matter is composed of indestructible units, called atoms. 2) The shape of the atom determined the characteristics.

What did John Dalton state?

1) All matter is made up of individual particles called atoms that cannot be divided. 2) Pictured atoms of solid spheres.

Erwin Schrodinger.... 1) Proposed the _________________ _____________ model, which encompasses all of the possible what of electrons?

1) Electron Cloud model 2) locations

Name the 2 details mentioned about J.J. Thomson's Plum Pudding Model.

1) Entire mass is positively charged. 2) Negative charges are evenly distributed throughout.

What did Neils Bohr do?

1) He focused on electrons in fixed orbits. 2) Identified the idea of energy levels.

Name the 2 details mentioned about Ernest Rutherford's experiment.

1) He sent positive charged "alpha" particles through thin, gold foil. 2) Particles all deflected from a central point.

In J.J. Thomson's Plum Pudding Model.... 1) The entire mass is ____________________ charged. 2) Negative charges are ______________ distributed throughout.

1) Positively 2) evenly

Democritus stated: 1) All matter is composed of indestructible units, called _____________. 2) The shape of the atom determined by _____________________________.

1) atoms 2) its characteristics

Neils Bohr: 1) Focused on _________________ in fixed orbits. 2) Identified the idea of what?

1) electrons 2) energy levels

John Dalton stated: 1) All matter is made up of __________________ particles called atoms that cannot be _________________. 2) Pictured atoms of __________ _________________.

1) individual; divided 2) solid spheres

In Ernest Rutherford's experiment.... 1) He sent positive charged "alpha" particles through what? 2) Particles all ___________________ from a central point.

1) thin, gold foil 2) deflected

Each element has a different what?

Atomic Number

Which scientist was the one who did an experiment?

Ernest Rutherford

What did Ernest Rutherford conclude from his experiment?

He concluded that the atom's positive charge is all concentrated in the center of the atom.

How did Dalton describe atoms?

He described atoms as solid spheres that cannot be divided.

Why did Erwin Schrodinger think Bohr was INCORRECT?

He thought electrons had NO fixed orbits.

What is the purpose of the Electron Cloud Model?

It encompasses all of the possible locations of electrons.

Which scientist created the "Plum Pudding Model"?

J.J. Thomson

Which two scientists proposed models?

J.J. Thomson (Plum Pudding) & Erwin Schrodinger (Electron Cloud)

Atoms are assumed _________________.

Neutral

Identify the relative masses (amu) of a proton, electron, & neutron.

Proton = 1 amu Electron = 1/1836 amu Neutron = 1 amu

Name the Subatomic particles.

Protons, Electrons, & Neutrons

Identify the symbol, location, and charge of an electron.

Symbol: e- Location: In the space outside the nucleus Charge: -1

Identify the symbol, location, and charge of a neutron.

Symbol: n OR n^0 Location: In the nucleus Charge: None

Identify the symbol, location, and charge of a proton.

Symbol: p+ Location: In the nucleus Charge: +1

What does the atomic number tell you about the atom?

The atomic number tells you how many protons are in the element.

In the Electron Cloud model, why does the cloud have different areas of density?

The cloud is denser in area where electrons are more likely to be found.

What is the atomic mass of an atom?

The number of protons & neutrons in an atom.

The amount of positive charge varies with the __________________.

element

In an atom, the number of protons _____________ the number of electrons.

equals

Each nucleus contains at least ________________ particle with a positive charge.

one