Units 14-15 Flashcards
True or False: The molecular model tells us something about the internal structure of molecules.
FALSE
True or False: Electrons have the same mass and charge in every type of atom.
True
Which part of the atom determines the unique nature of the atom?
The positive part.
True or False: Protons have the same mass and charge in every type of atom.
FALSE
Same charge, different mass
Which has smaller mass, electron or proton?
Electron
What is the Plum Pudding model?
The positive charge is spread equally throughout the atom. Electrons are sprinkled throughout the positively charged region.
What are alpha particles?
High energy, positively charged particles. Can break apart atoms.
It’s a helium nucleus emitted in radioactive decay.
True or False: The atomic nucleus is INCREDIBLY dense
True
Is the nucleus positive or negative?
Positive
What is the solar system model of the atom?
A model of the atom in which the electrons orbit the small, dense, positively charged nucleus in elliptical paths.
What is an emission spectrum?
The set of colors of light given off, or emitted by, an object.
Not always a rainbow
What are discrete emission spectra?
Spectra that don’t give off a rainbow, selective colors based on the properties of the materials.
What are emission lines?
The sharp, easily identifiable lines of emission from discrete emission spectra
True or False: The colors in the spectrum of a hot object depend only on the object’s temperature, not its material composition.
TRUE
True or False: Hot objects glow at all wavelengths
True
True or False: When atoms change from a high energy state to a low energy state, they emit the energy difference (conservation of energy) as light.
True
True or False: The colors in the spectrum of an object being heated depend only on the temperature and not on its material composition
True
True or False: Discrete colors = discrete energies
True
What does quantized mean?
The number of possible values has been restricted.
Quanta, quantum, quantized = some kind of restriction on the possible values, discrete
What properties of atoms have a dependence on discrete integers (quanta)?
Angular momentum
Energy
What is the modified solar system model?
AKA the Bohr model. With restricted circular orbits of electrons around a nucleus.
Takes Quanta integers into account (discrete)
What does n represent in the Bohr model?
The radius (distance) between the electron and the nucleus
What happens to the energy and radius of the electron orbit as the quantum number increases?
They increase
True or False: Electrons can occupy the space between the quantum orbits.
FALSE
They are restricted to their specific orbit
What is the postulate of quantization of the Bohr model?
Any electron in an orbit (n) possesses a specific energy.
How do electrons lose energy and fall down to a lower n state?
By emitting energy as a photon of LIGHT.
What determines the frequency and color of the light that is emitted by an electron?
It is the energy difference between the two orbits.
Energy of outer orbit - energy of inner orbit = energy of emitted photon.
True or False: Violet photons are more energetic than red photons
True
Where does the energy come from that causes electrons to be in a higher state (n orbit)?
Collisions.