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Flashcards in 4.1 Deck (10)
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1
Q

the smallest unit of an element that maintains the properties of that element

A

atom

2
Q

a subatomic particle that has a negative charge

A

electron

3
Q

in physical science,an atom’s central region, which is made up of protons and neutrons

A

nucleus

4
Q

a region around the nucleus of an atom where electrons are likely to be found

A

electron cloud

5
Q

He though that matter is composed of atoms. He also believed that you would never end up with a particle that could not be cut.

A

Democritus

6
Q

He believed you would never end up with a particle that could not be cut.

A

Aristotle

7
Q

He though all substances are made of atoms. Atoms are particles that cannot be created, divided, or destroyed

A

Dalton

8
Q

He discovered that there are small particles inside the atom. This mean atoms can be divided into smaller parts. He invented a cathode-ray tube

A

Thompson

9
Q

He decided to test Thompson’s theory. He designed an experiment to study the parts of the atom. He aimed a beam of small, positively charged particles at a thin sheet of gold foil. He put a special coating behind the foil. The coating glowed when it was hit by the positively charged particles. He could see where the particles went after hitting the foil.

A

Rutherford

10
Q

disproved Bohr’s theory and present day experiments prove that electrons move randomly in space within the atom known as

A

Shrodinger and Heisenberg