A-LEVEL PHYSICS: 8.1.2: Changning Models of the Nucleus (SaveMyExams)

Question 1

John Dalton’s Atomic Model (1803):

Answer 1

all tiny solid particles

Question 2

Dalton’s atomic model proposed that: (3)

Answer 2

-atoms are the smallest constituents of matter and cannot be broken down any further

-atoms of a given element are identical to each other, & atoms of different elements are different from one another

-when chemical reactions occur, the atoms rearrange to make different substances

Question 3

J.J. Thomson’s Atomic Model (1897):

Answer 3

plum pudding model

Question 4

Thomson discovered the…

Answer 4

electron

Question 5

Thomson’s atomic model proposed that: (2)

Answer 5

-atom consists of + & - charges in equal amounts, so neutral overall

-atoms can be modelled as spheres of + charge with uniformly distributed charge & density. e- suspended throughout

Question 6

Rutherford, Geiger and Marsden set out to test the…

Answer 6

plum pudding model

Question 7

Niels Bohr’s Atomic Model (1913):

Answer 7

improved upon Rutherford’s model

used mathematical ideas to develop the ‘planetary model of the atom’

Question 8

Bohr’s atomic model proposed that: (2)

Answer 8

-electrons orbit the nucleus

-electrons occupy energy levels (shells) around the nucleus