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