Chem chapter 2

Atomic #

Number of p+

Atomic mass

P+ and N

Greek philosophers

Introduce atoms

Made of 4 elements

Earth 

Wind 

Fire 

Water

J.j. Thompson 

Discovered plum pudding model 

Plum pudding 

Jj Thompson Shot cathode rays(-) at an atom and the rays repelled so he discovers the electron 

John dalton

Hard sphere model

Hard sphere 

1. Elements are made of extremely small particles

2. Atoms of a given element are identical in size mass and other properties

3. Atoms cannot be subdivided created or destroyed

4. Atoms of different elements combine in simple whole number ratios to form chemical compounds.

5. In chemical reactions atoms are combined separated or rearranged

T/f Elements are made of extremely small particles

True

T/f Atoms of a given element are identical in size mass and other properties

False

T/f Atoms cannot be subdivided created or destroyed

False

T/f Atoms of different elements combine in simple whole number ratios to form chemical compounds.

True

T/f In chemical reactions atoms are combined separated or rearranged

True

Rtherford 

Gold foil

Gold foil

Rutherford shot alpha (+) rays at gold foil a small amount deflected so there must be a small dense positive nucleus in the middle