ch 2 Flashcards Preview

Chem 200 > ch 2 > Flashcards

Flashcards in ch 2 Deck (33):
1

Who proposed the atomic theory?

John Dalton

2

Who discovered the electon?

Thomson

3

Who measured the electron and measured their charge to mass ratio?

Millikan

4

Who discovered the nuclear theory of the atom?

Rutherford

5

Nuclear theory

the atom is mainly empty space, with most of its mass concentrated in the nucleus and most of its volume occupied by very light electrons

6

Who discovered neutrons?

Chadwick

7

radioactivity

unstable nucleus of atoms

8

atomic mass

#neurons + #protons

9

atomic number (Z)

# of protons

10

Isotopes

atoms of an element with the same number of protons but different number of neutrons

11

Ions

charged atoms

12

cation

positive ion, lost electron

13

anion

negative ion, gained electron

14

how is the per table arranged?

rows of increasing mass and similar properties

15

in periodic table, the columns are called

groups

16

in the periodic table, the rows are called

periods

17

who arranged the periodic table?

Mendeleev

18

metals

good conductors of heat/electricity, malleability, ductility, shiny, tend to lose electrons

19

non metals

poor conductors of heat/electricity, can be found in any state, tend to gain electrons

20

metalloids

some are semiconductors, mixed properties

21

main-group elements

predictable based on their position in the periodic table

22

transition elements/ metals

less predictable based on the periodic table

23

noble gases

un-reactive, complete, stable filled p orbitals

24

alkali metals

reactive metals

25

alkaline earth metals

fairly reactive

26

halogens

very reactive non-metals

27

more metallic in color..

more likely to lose electrons

28

cation element

"ion"

29

anion element

" --ide ion"

30

molar mass

atomic mass, g/mol

31

mole

number of atoms in a specific element

32

avogadro's number

1 mol of anything = 6.022 x 10^ 23

33

moles are always related to

mass