Atomic theory

Question 1

Democrtius

Answer 1

Greek philosopher that stated matter could be infinitely divided

Question 2

John Dalton

Answer 2

developed the modern atomic theory

All matter is composed of atoms

All atoms of a given element are alike. Atoms of different elements are different

Compounds are formed when atoms unite in fixed proportions

Chemical reactions involve a rearrangement of atoms. Atoms are not created or destroyed

Question 3

Law of Conservation of Mass

Answer 3

Atoms cannot be created or destroyed; thus total mass of a reaction remains constant

Question 4

Law of Constant Composition

Answer 4

All samples of a compound have the same composition

Question 5

Law of Multiple Proportions

Answer 5

Atoms combine in simple whole number ratios

Question 6

Plum Pudding model

Answer 6

Atom is a solid positive sphere with negative charges imbedded throughout

Question 7

Ernest Rutherford performed the gold foil experiment

Answer 7

When he shot a beam of alpha particles at a sheet of gold foil, a few of the particles were deflected. He concluded that a tiny, dense nucleus was causing the deflections.

Question 8

Rutherford cont Nucleus

Answer 8

Nucleus carries a positive charge equal in magnitude to the electron

Question 9

What is the perecentage of a nucluasus in an atom

Answer 9

Nucleus contains 99.9% of the mass of an atom, while its diameter is only 0.01% of an atom

Question 10

Which scientist model is refered as the “Plum pudding¨

Answer 10

J.J thompson

Question 11

Bohr plantery model

Answer 11

the electrons encircle the nucleus of the atom in specific allowable paths called orbits

Question 12

cathode ray tube expirement

Answer 12

ran a electric current through a tube, placed a magnet atound the tube, it repels, negtive enegry is in the current.