Chapter 4 Study Guide Flashcards
What was John Daltons Atomic Theory
- All matter is made of atoms
- Atoms of a element are the same in mass
- Combinations are made up of more than one kind of atoms
Describe in detail John Daltons model of the atom
A tiny solid sphere with a predictable mass for a given element
What did JJ thomsons experiments provide evidence for ?
That the Atom contains negatively charged particles
What did Rutherfords gold foil experiment provide existence for ?
There is a dense positively changed mass in the center of an atom
Who provided evidence for the existence of a nucleus in an atom ?
Ernest Rutherford
In an atomic model that includes a nucleus, where is the subatomic that has a positive charge located?
In the center of an atom
Which subatomic particle has a negative charge?
Electron
What are the subatomic particles, give the name, charge, location, and where it is located.
Subatomic particles are particles smaller than an atom
Elections: negative, election orbital, o Mass
Neutron: no charge, in nucleus, 1 mass
Proton: positive, in nucleus, 1 mass
What is unique for any given element?
Number of protons
How would you find the number of neutrons in an atom?
Mass-atomic number
In Niels Bohrs model of an atom, how do the elections move?
Like planets orbiting the sun
What does the electron cloud model describe?
The most likely location of elections in atoms
What is the difference between an atom in the ground state and an atom in an excited state?
Atoms in an excited state have more energy and is less stable than at ground state
The glowing of a neon light cause by electrons emitting energy as they do what?
Move from higher to lower energy levels
According to ______ all matter was made up of four elements: earth, air, fire and water.
Aristotle
John Dalton observed that elements always combine in the same ratio to form a particular _____.
Compound
The results of Rutherfords gold foil experiment demonstrated that the ___ occupies a very small amount of the total space inside an atom
Nucleus
Protons and ____ are found in the nucleus of an atom
Neutrons
In Bohrs model of the atom, _____ move in fixed orbits around the nucleus
Elections
The region in which an electron is most likely to be found is called an _____.
Orbital
An atom in which an electron has moved to a higher energy level is in a ____ state
Excited
What did Rutherford conclude about the location of positive charge in an atom?
The positive charge is concentrated in the nucleus
Which of the three subatomic particles-proton electron or neuron- has the least mass?
Electron
In an atom has 32 protons and 38 neurons, what is its mass number ?
70
If An atom of an element has a mass number of 31 and 16 neurons in its nucleus; what is the atomic number of the element?
15
In an atom of germanium has a mass number of 70 and an atomic number of 32 how many neutrons are in its nucleus
38
What did Bohrs model of the atom do that Rutherfords model did not ?
It focused on electrons
How did the electron cloud model of the Atom represent the locations of the elections in the atoms?
It is the visual model of the most likely location of electrons
How does the state of atoms in a neon light change when light is emitted
Atoms state changes from excited to ground state
What is the main difference between the atomic model In panel 1 and the model In panel 2.
Panel 1 doesn’t have subatomic particles while panel 2 does
What is the main difference between the atomic model in panel 2 and panel 3.
The subatomic particles are orbiting around the center in panel 2 and in panel 3 electrons are represented by a cloud
How is the atomic model in panel 2 helpful to your understanding of the atom? In what way is it not helpful?
Good- shows general location of subatomic particles
Bad- It implies that electrons travel in a fixed orbit
The Greek philosopher Democritus coined a what word for a tiny piece of matter that can not be divided?
Atom
