ch1- atomic structure

Question 1

whatre the 3 states of matter

Answer 1

liquids solid and gas

Question 2

describe movement and arangement of particles in gas molecules

Answer 2

-easily compressed
-particles are widely spaced
-have no fixed volume so theyt take shape of container
-move rapidly and quickly

Question 3

describe movement and arrangement of particles in liquid molecules

Answer 3

-closely packed little spaces
-can flow
-no fixed volume so they take shape of their container
-flow

Question 3

describe movement and arangement of particles in solid molecules

Answer 3

-fixed shape and volume
-particles packed closesly in a fixed pattern
-vibrate which generates kinetic energy
-cant be compressed

Question 3

whatre the 2 changes of states that involve particles coming closer together and where do they transfer energy

Answer 3

-condensation (gas to liquid)
-freezing (liquid to solid)
they transfer energy to their surroundings since theyre reforming bonds between particles (exothermic)

Question 4

whatre the 2 changes of states that involve particles seperating and where do they transfer energy

Answer 4

-melting (solid->liquid)
-evaporation (liquid->gas)
they take in energy from surrounding (endothermic)

Question 5

whatre the 2 factors that effect diffusion

Answer 5

• state of matter (diffusion takes place faster in gasses than liquids)
  -density of particles (small and light particles diffuse faster than heavy larger ones)

Question 6

stronger forces between particles=…

Answer 6

more energy required to break up the intermolecular forces

Question 7

define and give an example of a molecule

Answer 7

2 or more atoms held by chemical bonds ex-oxygen or water

Question 8

define a compound

Answer 8

2 or more different elements held together by chemical bonds

Question 9

define and give an example of mixture

Answer 9

-2 or more substances that are physically but not chemically bonded
ex- air, since it has oxygen carbon dioxide and nitrogen

Question 10

state the relative mass of each subatomic particle

Answer 10

proton-1
neutron-1
electron- very small (0)

Question 11

state the relative charges of each subatomic particle

Answer 11

proton +1
electron -1
neutron- 0

Question 12

whats the atomic number

Answer 12

number of electrons=protons in an element

Question 13

what does the mass number constist of

Answer 13

proton+neutron

Question 14

what do groups share

Answer 14

similar chemical properties due to same amount of electrons on outer shell

Question 15

what 4 scientists were involved in the nuclear model

Answer 15

• jj thompson
  -niels bohr
  -ernest rutherford
  -james chadwick

Question 16

describe the plum pudding model

Answer 16

-jj said that the atom was a dense sphere with equally distributed mass. electrons embedded into the sphere

Question 17

how was the nuclear (nucleus) model disovered

Answer 17

alpha particle scattering experiment
-ernest found that atoms were mainy empty space with a dense and positively charged nucleaus that orbits electrons

Question 18

what did niels bohr dicover

Answer 18

that electrins orbit the nucleaus at specific energy levels

Question 19

what did chadwick discover

Answer 19

that a the nucleas also contained neutrons

Question 20

define an isotope

Answer 20

an atom with the same number of proton but different neutrons

Question 21

whats relative atomic mass

Answer 21

the average mass of an isotope

Question 22

whatre ions

Answer 22

atoms with an overall charge due to loosing or gaining an electron

Question 23

why do atoms have no overall charge

Answer 23

cause proton = electron so the charges cancel eachother out

Question 24

whats the max number of electrons held in the 1st,2nd,and 3rd shell

Answer 24

2,8,8

Question 25

why do elements in the same group have similar chemical properties

Answer 25

because they all have the same amount of electrons on their outter energy shells