Atomic Models
Who first suggested that matter is made of tiny, indivisible particles called atomos?
Who is Democritus?
Which subatomic particle determines the identity of an atom?
What is a proton?
Whose atomic theory said that atoms can’t be created, destroyed, or divided into smaller particles?
Who is John Dalton?
Who created the first periodic table of elements?
Electrons that are farthest from the nucleus are called what?
Which philosopher argued that all substances were made of earth, air, fire, and water?
Who is Aristotle?
Which subatomic particle has no charge but adds mass to the atom?
What is a neutron?
What scientific law says matter cannot be created or destroyed, only changed?
What is the law of conservation of mass?
The columns on the periodic table are called what?
What are groups (or families)?
When electrons absorb energy, they jump to ___ energy levels.
What are higher energy levels?
Which scientist proposed the "plum pudding" model of the atom?
Who is William Thomson (Lord Kelvin)?
Which subatomic particle orbits the nucleus and has a negative charge?
What is an electron?
Dalton’s theory said that atoms of the same element have the same ___ and ___.
The rows on the periodic table are called what?
When electrons fall back down to lower levels, what do they release?
What is energy (often as visible light)?
Whose gold foil experiment showed that atoms have a dense, positively charged nucleus?
Who is Ernest Rutherford?
Which subatomic particle is most important in determining an atom’s chemical properties?
What are electrons?
Which model describes electrons as moving in a cloud of probability rather than fixed orbits?
What is the quantum mechanical model (electron cloud model)?
Elements in the same group share what in common?
What are similar properties?
Why do fireworks release different colors of light?
Which scientist’s model described electrons moving in fixed orbits around the nucleus?
Who is Niels Bohr?
Isotopes have the same number of these but different numbers of neutrons.
What are protons?
What lesson did Rutherford teach us about unexpected experimental results?
What is to let unexpected results lead to new questions and discoveries?
Which group of elements is the most stable and least reactive?
What are the noble gases (Group 8A)?
Going down Group 1 (the alkali metals), what happens to reactivity?
What is it increases?