Chapters 1 and 2 COPY Flashcards
(62 cards)
1
Q
Chemistry
A
-The scientific study of matter
2
Q
Matter
A
- All the physical material in the universe
- Anything that has mass and occupies space
- Made up of atoms
- Subsets: Mixtures and pure substances
3
Q
Atoms
A
- The smallest building blocks of matter
- Nondivisible
4
Q
Molecules
A
-2 or more atoms joined in specific shapes
5
Q
Mixtures
A
- Homogeneous: same concentration throughout
- Heterogeneous: Inconsistent throughout, mixing phase
6
Q
Pure Substance
A
- Elements
- Made up of atoms
- Compounds: Combination of elements
7
Q
Property
A
-Any characteristic that allows us to recognize a particular type of matter and distinguish it from other types
8
Q
Elements
A
-Over 100 substances that matter is comprised of
9
Q
States of Matter
A
- Liquid
- Gas
- Solid
10
Q
Liquid
A
- Distinct volume independent of its container
- Takes the shape of its container
- Not compressible
- Molecules packed closely together but still move rapidly
11
Q
Gas
A
- No fixed volume or shape
- Uniformly fills its container
- Can be compressed or expanded
- The more it is compressed, the increase in collisions, and vice versa
12
Q
Solid
A
- Has a fixed shape and volume
- Not compressible
- Molecules tight together, wiggle only slightly
13
Q
Molecular Elements
A
Diatomic: N,O,H,F,Cl,Br,I
Polyatomic: P, S, Se
14
Q
Physical Properties
A
-Can be observed w/o changing identity and composition
Ex: color, classification
15
Q
Chemical Property
A
-Describes the way a substance may change or react
Ex: will disolve, flammable
16
Q
Intensive Properties
A
-Does not depend on the quantity of sample
Ex: density
17
Q
Extensive Properties
A
-Depends on quantity of sample
Ex: Mass and volume
18
Q
Physical Changes
A
-Change in appearance
19
Q
Chemical Changes
A
- Transforming into new or different substance
- Due to a reaction
20
Q
Separations
A
- Uses physical properties
- Filtration
- Distillation: Uses boiling point to separate homogeneous mixture
- Chromatography: Separation of colors
21
Q
Kelvin–> C or C–> Kelvin
A
Tk= Tc +273.15
22
Q
C–> F or F–> C
A
Tc= (Tf-32)/ 1.8
23
Q
Precision
A
- “Rreproducability” or consistency in measurements
- Hitting the same place every time
24
Q
Accuracy
A
- Agreement w/ the true value
- Hitting the bullseye
25
SigFigs
- Nonzeros= always significant
- Zeros
- Leading: 0.000123 = 3 sigfigs
- Trailing: 1,230,000= 3 sigfigs
- Captive: 0.1043= 4 sigfigs
- Decimal: start at left, no decimal start at right
- Exceptions: exact numbers in counting, in an equation, or definition
26
Statistic Error (Systematic)
-Can't be free of error
-Want to minimize error
3 types:
-Instrument error
-method error
-personal error
-Systematic category of errors, reproducible
-Random error: uncontrollable errords, ex= earthquake ruins measurements
27
Mean
- X with line over it
| - Sum of measurements/ number of measurements
28
Standard Deviation
Square root (sums of the individual measurements - average)^2 / n-1
29
Average Deviation
Sum of (individual measurements - average)/ n
30
% error
true value- actual value/ true value x 100%
31
3 Laws
1. Law of Conservation of Mass
2. Law of Definite Proportions
3. Law of Multiple Proportions
32
Law of Conservation of Mass
- LaVoisier
- Mass is neither created nor destroyed
- Total mass of reactants= total mass of products
33
Law of Definite Proportions
- Joseph Proust
| - A given compound contains same proportions of elements by mass
34
Law of Multiple Proportions
- Dalton
- When two elements form a series of compounds, the ratio of the second element to 1g of the first element is always reduced to whole numbers
35
Dalton's Atomic Theory
1. Each element= atoms
2. All atoms of same element =identical, atoms of one element are different from the atoms of other elements
3. Atoms of one element can't be changed to atoms of another element
- Atoms are neither created nor destroyed
4. Compounds are formed when atoms of more than one element combine; a given compound always has the same relative number and kind of atoms
36
JJ Thomson
- Electrons move from negative cathode to positive anode
- Described cathode rays as negatively charged (e-)
- Measured change to mass ratio
* Plum pudding model
37
Robert Millikan
- University of Chicago
| - Determined mass of an electron using oil drop experiment
38
Henri Becquerel
-Discovered radioactivity
39
Marie Curie
-Identified and isolated subatomic particles
40
Ernest Rutherford
- Discovered three types of radiation
1. Alpha particles, positive charge
2. Beta particles, negative charge
3. Gamma rays, uncharged and high energy
- Discovered protons
41
Plum Pudding Model
- JJ Thomson
- Debunked by gold foil experiment
- negative electrons within positive charge spread throughout sphere
42
Rutherford's gold foil experiment
- A small dense nucleus at center of atom
- Positively charged
- Atom= mostly empty space
43
James Chadwick
-Discovered neutrons
44
Subatomic Particles
- Proton= positive
- Neurton= neurtral
- Electron= negative
45
Mass number
Protons+ neutrons
46
Atomic number
of protons
47
Isotopes
Elements w/ same number of protons, diff # of neutrons
48
Atomic weight
```
sum of (% in decimal x atomic mass)
-Tested using mass spectrometer
```
49
Period
-Row on periodic table
50
Group
-Column on periodic table
51
Metals, Nonmetals, Metalloids
Metals: Left of zigzag
Nonmetals: Right of zigzag
Metaloids: B, Si, Ge, As, Sb, Te
52
Molecular Formula
-Actual formula of molecule
| Ex: H2O= water
53
Empirical
- Smallest, whole # ratio of the atoms
| - Does not exactly indentify formula
54
Ions
- A charged atom
- Cation= positive
- Keep name in ionic compounds
- Anion= negative
55
Prefixes
```
Mono- 1
Di- 2
Tri- 3
Tetra- 4
Penta- 5
Hexa- 6
Hepta- 7
Octa- 8
Nona- 9
Deca- 10
```
56
Hydrated Compounds
- Ionic compound w/ attached H2O
- Ex: MgSO4 x 7H2O
- Magnesium Sulfate Heptahydrate
57
Periodic Groupings
Hydrogen= nonmetal
- Alkali Metals= 1A
- Alkaline Earth Metals=2A
- Halogens= 7A
- Noble Gases= 8A
- Metalloids: B, Si, Ge, As, Sb, Te, Po
58
Derived Unit
- Come from the multiplication or division of SI Units
| - Ex: speed= distance/time
59
Qualitative Analysis
-The determination of the presence or absence of a particular substance in mixture
60
Quantitative Analysis
-The determination of the presence or absence of a given substance that is present in a sample
61
Structural Formula
-stick drawings that show how atoms are joined together
| Ex: H-O-H is h2o
62
Molecular Compounds
-Compounds composed of molecules that contain more than one type of atom
