Chapter 02: Atoms and Elements Flashcards Preview

Gen Chem 01 > Chapter 02: Atoms and Elements > Flashcards

Flashcards in Chapter 02: Atoms and Elements Deck (45):
1

Law of conservation of mass

Matter is neither created nor destroyed in a chemical reaction

Mass of reactants = mass of products

2

Law of definite proportions

All samples of a given compound have the same proportions of their constituent elements

Water is always H20

3

Law of multiple proportions

Atoms of two or more elements may combine in different ratios, producing various compounds

4

Subatomic particles

Election (e-) - negative charge, mass is minute

Proton (p) - positive charge, mass = 1840x an electron's

Neutron (n) - neutral particle, GREATEST MASS

5

Cathode rays

Beam of particles, negatively charged

6

Cathode

Negatively charged electrode

7

Anode

Positively charged electrode

8

Radioactivity

Spontaneous emission of particles and/or radiation

9

Radioactive element

Spontaneously emits radiation

10

Alpha particles

Positively charged particles

11

Beta particles

Negatively charged particles

12

Gamma rays

Neutral charge, high-energy radiation

13

Nuclear theory

Nucleus = most of atom's mass and all of its positive charge

Empty space = most of the atom

# of protons = # of electrons, so atoms are neutral

14

Periodic table

Elements are in order of increasing atomic number

Row = period
Column = group/family

15

Group 1A

Alkali metals

16

Group 2A

Alkaline earth metals

17

Groups XB

Transition metals

18

Groups XB - inserted rows

Inner transition metals

19

Group 7A

Halogens

20

Group 8A

Noble/inert gases

21

Atomic number

Z
Number of protons

22

Mass number

A
Number of protons + neutrons

23

Chemical symbol

X
Chemical abbreviation

24

X-A

Chemical-Mass #

25

Molecule

2+ atoms in DEFINITE arrangement, held together by chemical forces

26

Diatomic molecule

2-atom molecule

27

Diatomic molecules in nature (7)

Hydrogen (H)
Nitrogen (N)
Fluorine (F)
Oxygen (O)
Iodine (I)
Chlorine (Cl)
Bromine (Br)

H + N through F + F down to I

"Have No Fear Of Ice Cold Beer"

28

Polyatomic molecule

>2 atom molecule

29

Polyatomic molecules in nature

Phosphorus (P4)
Sulfur (S4)
Selenium (Se4)
(Oxygen (O3))

(remaining 3 Other Nonmetals angled in diatomic molecules N, O, F, Cl, Br

30

Cation

Positively charged ion

31

Anion

Negatively charged ion

32

Monatomic ion

1-atom ion

33

Polyatomic ion

2+ atom ion

34

Main-group/representative elements

A groups
Properties tend to be largely predictable based on location in table

35

Transition elements

B groups
Properties tend to be less predictable simply based on location in table

36

Metals

Solids at room temperature (EXCEPT MERCURY, Hg)
Lustrous (shiny)
Good conductors of heat/electricity
Malleable
Ductile
High melting points, high densities
Tends to lose electrons

Form ionic compounds with nonmetals
Rarely combine with other metals

37

Metals found in free states (3)
"Noble metals"

Silver (Ag)
Platinum (Pt)
Gold (Au)

38

Nonmetals

Not lustrous (shiny)
Poor conductors of heat/electricity
Not malleable
Not ductile
Fairly low melting points & densities
Tend to gain electrons

Form molecular compounds with each other (and metalloids)
Form ionic compounds with metals

BROMINE (Br) is liquid at room temperature

39

Metalloids

Properties are between metals and nonmetals
Some are semiconductors

Boron (B) through Astatine (At)
EXCLUDING Aluminum (Al) (and Polonium (Po))

40

Transition metals with predictable charge (3)

Silver (Ag) - Group 1B = 1+ charge

Zinc (Zn) - Group 2B = 2+ charge
Cadmium (Cd) - Group 2B = 2+ charge

41

Atomic mass

amu
Mass of an atom
Based on carbon-12

42

Average atomic mass

Weighted average of all naturally occurring isotopes of an element

Avg = (amu)(% abundance)+(amu)(% abundance)

43

Mass spectrometry

Separates particles according to mass
Used to determine masses of atoms & % abundances

44

1 mole (Avogadro's number)

6.022 x 10^23 objects

45

Molar mass

Mass of 1 mole of atoms of an element, expressed in grams

x amu = x g/mol