Atomic Theory
Who was the Greek Philosopher who theorized that all matter was made of invisible particles called atoms?
Democritus
Who's theory stated all elements consists of atoms that cannot be divided?
John Dalton
Which subatomic particles are located inside the nucleus of an atom?
Protons & Neutrons
Group 16 is called _____________________
The Oxygen Group
The sum of the number of protons and neutrons inside the nucleus is called the ______________
Mass Number
Atomos means.....
Uncuttable
This Scientist was responsible for discovering the electron
J.J Thomson
What is the proper charges for protons, neutrons and electrons?
Protons = Positive
Neutrons = Neutral
Electrons= Negative
Elements in Group 17 are called
Halogens
Elements on the modern periodic table are arranged by their ________
Atomic Number
The smallest particle that still can be considered an element
Atoms
Did Ernest Rutherford conduct a Gold Foil Experiment?
True or False
Yes, True
The number of protons an atom contains is identified by the ________________ of the periodic table.
Atomic Number
Elements in Group 15 are called _____________
Carbon Group
Elements that have chemical and physical properties of both metals and nonmetals are called ______________
Metalloids
The year 1590 saw the invention of the ........
Microscope
Which scientist discovered a nucleus with a positive charge making up the center of an atom, he called it a proton?
Ernest Rutherford
Who organized the first periodic table that was based on the elements' atomic masses?
Dimitri Mendeleev
Elements in groups 3-12 are called ________
Transition metals
Valence Electrons are located on the __________
On the outer layer orbiting the nucleus.
Who believed in all matter being composed of the four elements: earth, fire, water and air
Aristotle
A Danish scientist who worked with Rutherford, described the motion of electrons around the nucleus.
Bohr
Group 1 elements are also called _________________
Group 13 is called ____________
The Boron Group
The periodic table is organized by __________ & _____________
Periods and Groups