The Old Days
What was the word Aristotle used to describe "matter"?
Hyle
The "plum pudding" model included these two subatomic particles.
A proton with electrons inside
____ are atoms of the same element with a different number of neutrons
Isotopes
The time it takes for half the amount of a radioisotope to decay
Half-life
An atom has an atomic number of 17 and a mass number of 35. What are its protons, neutrons, and electrons?
Protons: 17, Electrons: 17, Neutrons: 12
Democritus
Rutherford was known for this experiment that tried to prove atoms were mostly empty space
Gold Foil Experiment
A weighted average based on the mass and relative abundance of all naturally occurring isotopes.
Atomic mass
This kind of radioactive particle is made of electrons, has a negative charge, and has intermediate penetrating power
Beta particles
An element has 30 protons and 35 neutrons. What are its atomic number and mass number?
Atomic number: 30, Mass number: 65
He worked on gas laws, even creating one of his own
Robert Boyle
This model for an atom included energy levels for electrons.
The Bohr Model
Atoms always have what kind of charge?
This type of radiation has a positive charge and usually involves Helium
An atom has a mass number of 39 and 19 electrons. What are its protons and neutrons, and what element is it?
Protons: 19, Neutrons: 20, Potassium
The Father of Modern Chemistry
Antoine Lavoisier
Erwin Schrödinger had a strange idea: electrons were found around the nucleus not in fixed orbitals but in this kind of shape
Clouds (The electron cloud model)
0. An electron is not considered to have weight. Protons are 1, and Neutrons are 1
True or False: Nuclear Reactions violate the conservation laws
True. Matter gets converted to energy, and elements can change to different elements
A mystery element has three isotopes:
What is its atomic mass?
(50 × 0.20) + (51 × 0.30) + (52 × 0.50)
= 10 + 15.3 + 26
= 51.3 amu
The man who came up with atomic theory
John Dalton
In Neil Bohr's model, electrons could "jump" levels. The energy required to do so was called this
Quantum
On the periodic table, does atomic number increase or decrease as you go down?
Increase
The term for when one element converts to another element in a nuclear reaction
Transmutation. Trans means to change
If you are given an isotope of a random element and only its atomic number and not the mass number, could you find out the number of neutrons?
No. Since it is an isotope, you need to know the mass number to find the number of neutrons