Atomic Theory 1
Atoms that have a net positive or negative charge.
What are ions?
Electrons have a _______ charge.
Negative
What was discovered by Rutherford?
Substances made of particles that have mass and volume.
What is matter?
What is 22?
An atom has an equal number of protons and electrons.
What is electrically neutral?
This Greek philosopher was the first to imagine everything is made of tiny, indivisible particles.
Who is Democritus?
The Scientist who stated that atoms can't be created, divided, or destroyed?
Who is Dalton
The scientists who came up with the "Plum-Pudding" model.
Who is Thompson?
The average atomic mass of Bromine
79.9
Thomson was the first person to discover...
Atoms have electrons
The scientist who stated that negatively charged electrons are embedded in a positively charged atom?
Who is Thomson
Which scientist first determined that electrons are found outside of the nucleus?
Rutherford
Who is Dalton?
The weighted average of all naturally occurring isotopes
What is average atomic mass?
Why did the positively charged alpha particles bounce back in Rutherford's Gold Foil Experiment?
They collided and were repelled by the positively charged nucleus
Most of the atom's mass is located here.
Where is the Nucleus
The Cathode Ray Tube experiment led to the discovery of the ________.
This scientist is credited for the discovery of the neutron.
Who is Chadwick?
This isotope has: Protons=50, Electrons=50, & Neutrons=70
What is Tin-120?
These particles make up the nucleus
What are the protons and neutrons
These make up all matter.
What are atoms?
Where are protons, neutrons and electrons located?
Where is the nucleus, nucleus, and electron cloud?
There were two major findings of Rutherford's Gold Foil Experiment. Name one.
The atom is mostly empty space
OR
There is a positively charged nucleus
This element has two isotopes:
Element- 40 (96.94%) & Element- 41 (3.06%)
Calcium