Hot seat: atomic history
The smallest particle of an element that retains that element’s properties is called a/an ______________________.
Atom
Who was the first to propose that matter is made up of atoms?
Democritus
What was Artistotle’s Contribution to our understanding of the atom?
He proposed that matter was made of 4 elements: earth, air, fire, water
What is the difference between inductive and deductive reasoning?
Inductive is based on specific examples or evidence while deductive is based on intuition or “feeling”
Who established the metric system that we still use today?
Antoine Lavoisier
What was the nickname of the first model of the atom?
“pool ball” model
Who developed the first model of the atom?
Dalton
How did Thompson discover the electron How did Thompson discover the electron? (summarize results from cathode ray experiments!)
Experiment 1: speculated negative charge present in ray Experiment 2: proved ray was negatively charged Experiment 3: figured out ray was made of particles smaller than an atom
Explain Thomson’s model of the atom.
“Plum pudding Model” where plums were negative electrons in the pudding of positive charge space
What did Chadwick discover in an atom?
Neutrons
Explain Rutherford’s Gold Foil Experiment.
Rutherford shot positive particles at a piece of gold foil and some went through to the other side, some reflected slightly and some reflected a lot. This helped him realize there was a small positive component in the atom. (Nucleus)
What is the same about all electromagnetic waves?
Can travel in a vacuum and travels at the speed of light
What is a photon?
A particle of energy or light
What are the differences in wavelength and frequency when looking at microwaves and gamma rays?
Microwaves have longer waves with lower frequency Gamma rays have smaller waves with higher frequency
What happens to the energy released by a wave as the wavelength gets larger?
The amount of energy in a wave gets lower/smaller
Which rays have more energy than UV rays?
Gamma rays
What is the frequency of a 7.43 x 10-5 m wave?
What is the wavelength of a 1.528 x 10-13 J wave?
How is Bohr’s Model of the atom different than Rutherford’s Model?
Bohr said electrons travel at certain energy levels Bohr said electrons travel at certain energy levels. They can jump energy levels through absorbing or releasing energy.
What does a bright-line spectrum look like?
It has a black background with various “bright” color lines throughout
What is the name for the name given for the study of the energy which is given off and absorbed when atoms?
Spectroscopy
What is the difference between the excited and ground state of an electron?
Ground state: electrons are at their lowest possible energies Excited state: electrons have gained energy to move to a higher energy level
How do we see the specific colors for different chemicals when performing a flame test?
The color is produced because atoms will absorb energy to move to an excited state, but will then quickly release that energy in the form of light to move back to their stable state.