Chapter Two Flashcards
Were did the earliest recordings of matter come from?
in the fifth century BC by Ancient Greek philosophers
What did the word atom mean in intent Greek and what did they think of them?
The word atom meant “invisible” and they thought atoms as moving particles that differed in shape and size witch could join together.
What conclusion did these philosophers come to about matter?
That matter is consisted of various combinations of the four element fire, earth, air and water and could be infinitely divided.
Did they ever conduct experiments with to counter there theories?
No.
What was John Dalton’s atomic theory?
All matter is composed of small particles called atoms.
What dose an atom participate in?
The smallest part of an element, an atom takes effect in chemical change.
Can atoms be created or destroyed during a chemical change and what else?
Atoms can’t be created nor destroyed during a chemical change.
Who Conducted ted the electron experiment.
J.J. Thomson
What was a cathode ray tube?
A sealed class tube from witch all air had been removed, within were two metal electrodes.
What happened when voltage was applied to the electrodes?
A visible beam called a “Cathode Ray” appeared between them.
What was the effect of the beam?
It was deflected toward the positive charge and away from the negative charge.
What similar experiment was Cindi Ted and was was the result?
The ray was deflected by a magnetic field and the particles were much lighter than atoms.
What are the charges of protons, electrons and neutrons?
Protons = positive (+)
Electrons = negative (-)
Neutrons = natural ( )
Are atoms invisible and why or why not?
They are invisible due to the being too small to deflect light waves.
In the gold foil experiment ran by Rutherford why did some particles of the bream go through and why did some reflect of ?
Some passed though because of the presumed empty space inside the atom, while others reflected due to the alpha particles are positive and like charges repel each other.
