Unit 2

Question 1

What was Democritus known for?

Answer 1

Developed the 1st ideas of atomic structure

Question 2

What are the 4 components of Dalton’s Atomic Theory?

Answer 2

1. Matter is composed of small indivisible particles
2. An element is composed entirely of one type of element
3. Compounds contain atoms of 2 or more different elements
4. Atoms do not change their identities in chemical reactions

Question 3

Who discovered the electron and what did he use to discover it?

Answer 3

JJ Thomson, with cathode ray tubes

Question 4

Developed the Plum Pudding Model

Answer 4

JJ Thomson

Question 5

Who conducted the gold foil experiment?

Answer 5

Rutherford

Question 6

What were discovered in the gold foil experiment?

Answer 6

1. Alpha particles have a helium nucleus

2. Proved existence of a positively-charged nucleus

Question 7

Who discovered the nucleus?

Answer 7

James Chadwick (in 1932)

Question 8

What is the order of the evolving atomic models?

Answer 8

1. Democritus
2. Thomson’s Plum Pudding Model
3. Rutherford’s model

Question 9

Ion

Answer 9

Atom in which there are more or less electrons than protons

Question 10

What is radioactivity?

Answer 10

Loosing energy to gain stability

Question 11

What are the types of radiation

Answer 11

1. Alpha
   particle
2. Beta Particle
3. Gamma Particle

Question 12

What are the 4 types of radioactive decay?

Answer 12

1. Alpha Decay
2. Beta Decay
   3 Positron Emmision
3. Electron Capture

Question 13

neutron symbol

Answer 13

^1_0 n

Question 14

Proton symbol

Answer 14

^1_1 p

Question 15

Fission

Answer 15

Splitting of a nucleus into smaller nuclei

Question 16

Fusion

Answer 16

Combines 2 small nuclei to make one larger one

Question 17

What temp. Is needed for a thermonuclear reaction to occur?

Answer 17

40,000,000K to sustain it

Question 18

How many tons of coal does 1g of fission file create

Answer 18

3 tons of coal

Question 19

How many tons of coal does 1g of fusion fuel create?

Answer 19

20 tons of coal

Question 20

What is a half-life?

Answer 20

The time required for half the atoms of a radioactive nuclei de to decay.

Question 21

What does a shorter half life mean?

Answer 21

The nuclide is less stable.