Midterm 1 (Chapters 1-4) Flashcards
Metric System
Peta 15 Tera 12 Giga 9 Mega 6 Kilo 3 Deci -1 Centi -2 Milli -3 Micro (u) -6 Nano -9 Pico -12 Femto -15
Cathode Rays
- electrons move from cathode (-) to anode (+)
- rays are deflected by magnet
- no air in the tube
Millikan Oil Experiment
- found the charge of an electron: 1.602 x 10^-19
- used x rays to charge drops of oil between two plates, one positive and one negative
charge of an electron
1.602 x 10^-19 C
radiation
alpha: protons
beta: electrons
gamma: neutral
ammonium
NH4+
aluminum ion
Al+3
oxyanions
per ate (ClO4- perchlorate)
at (ClO3- chlorate)
ite (ClO2- chlorite)
hypo ite (ClO hypochlorite)
nitrate
NO3-
nitrite
NO2-
sulfate
SO4-2
phosphate
PO4-3
nitride
N-3
oxyanions –> acid
ate –> ic
ite –> ous
ClO4: perchlorate –> HClO4 perchloric acid
ClO3: chlorate –> HClO3 chloric acid
ClO2: chlorite –> HClO2 chlorous acid
ClO: hypochlorite –> HClO hypochlorous acid
sulfite
SO3-2
7 strong acids
HBr, HI, HCl, HClO4, HClO3, H2SO4, HNO3
8 strong bases
group 1 and heavy 2's LiOH NaOH KOH RbOH CsOH CaOH SrOH BaOH
is NH4 weak or strong?
ionic compounds containing NH4+ are weak
ionized vs. dissociated
molecular compounds ionize in water and ionic compounds dissociate in water
which anions are always soluble?
NO3- and CH3COO- and NH4+
acetic acid
CH3COOH
Cl- solubility rules
always soluble except compounds of Ag+, Hg2+2, Pb+2
Br- solubility rules
always soluble except compounds of Ag+, Hg2+2, Pb+2
I- solubility rules
always soluble except compounds of Ag+, Hg2+2, Pb+2
SO4-2 solubility rules
always soluble except compounds of Sr+2, Ba+2, Hg2+2, Pb+2
S-2 solubility rules
insoluble except compounds of NH4+, alkali metals, Ca+2, Sr+2, Ba+2
CO3-2 solubility rules
insoluble except compounds of NH4+ and alkali metals
PO4-3 solubility rules
insoluble except compounds of NH4+ and alkali metals
OH- solubility rules
insoluble except compounds of NH4+, alkali metals, Ca+2, Sr+2, and Ba+2
ammonia
NH3: common base, weak base, weak electrolyte
strong electrolytes?
all ionic compounds and strong acids/bases are strong electrolytes
weak electrolytes?
all weak acids/bases, water, NH3
nonelectrolytes?
all other compounds, usually molecular compounds like sugars, alcohols
reaction of CO3-2 or HCO3-2 with an acid?
first gives carbonic acid (H2CO3) which then breaks down into H20 and cO2
what combine with acids to form gases?
carbonates CO3 form CO2
sulfites SO3 form SO2
sulfides S form H2S
what are the driving forces of chemical reactions?
1) precipitation formation
2) neutralization - formation of weak electrolyte (H20)
3) formation of a gas
oxidation of hydrogen?
+1 when with nonmetals
-1 when with metals
chromium oxidation states
Cr+3 is green
Cr+6 is orange
activity series
- elements at the top are most easily oxidized and react readily
- metals on the list can be oxidized by the ions of the elements below it
what is a pure substance?
matter that has distinct properties and a composition that does not vary from sample to sample: water/NaCl
the observation that the elemental composition of a compound is always the same is known as…..
the law of constant compositions
what are some physical properties?
color, odor, density, MP, BP, hardness, conductivity
what are some chemical properties?
flammability, bubbles, heat, ppt, light
intensive vs. extensive
intensive does not depends on the amount of sample: temperature, MP, BP
extensive properties: depend on amount of sample: mass/volume
Kelvin to Celcius conversion
K = C + 273.15
1 mL = 1 cm^3
conversion factor
exact vs. inexact
s obtained by measurement are always inexact
precision vs. accuracy
precise: you get the same answer multiple times
accurate: you get the right answer
hypothesis
a possible explanation for certain phenomena based on preliminary experimental data
theory
more general, has a significant body of experimental evidence to support it, an explanation of natural behavior, explains why matter behaves the way it does
scientific law
summary or statement of natural behavior, tells how matter behaves
determinate errors
the source can be identified and theoretically eliminated : e.g. you read the top of the meniscus instead of the bottom
indeterminate error
cannot be identified: e.g. estimating the last digit
density
g/mL or g/cm^3usually
John Dalton’s Atomic Theory
1) each element is composed of extremely small particles called atoms
2) all toms of a given element are identical but the atoms of one element differ from the atoms of all other elements (false because of isotopes)
4) compounds are formed when atoms of more than one element combine; a given compound always has the same relative number and kind of atom
in a given compound, the relative numbers and kinds of atoms are constant
law of constant compositions - ratios are the same - this is pertaining to 1 molecule - no matter how much of the sample there is, the ratio will be the same H2O has 2 hydrogens and 1 oxygen no matter what
the total mass of materials present after a chemical reaction is the same as the total mass present before the reaction - atoms are neither created nor destroyed
law of conservation of mass
when two elements A and B form two different compounds, the masses of element B that combine with a fixed mass of element A can be expressed as a ratio of small whole numbers
law of multiple proportions: CO vs CO2
AB, AB2, AB3
if all masses of A are 1 g, then the mass of B in compound 1 vs. 2 vs. 3 are ratios X,Y,Z, and they’ll be ratios that are small whole numbers
C + O –> CO(AB) and CO2(AB2)
C is 1.0 g then O must be 1.33 g in CO and 2.67 g in CO2
2.67g/1.33g = 2
J.J. Thomson
charge:mass ratio 1.76 x 10^8 coulombs/g
angstrom to meters
1 A = 1 x 10^-10 m
mass number
superscript number: protons + neutrons
isotopes
same number of protons but different number of neutrons
atomic number
number of protons - all atoms of the same element have the same number of protons - # e- = protons in a neutral atom
average atomic weight
isotopes mass x fractional isotope abundance
groups
vertical columns - usually have similar physical and chemical properties
naming ionic and molecular compounds
ionic: metal and nonmetal: calcium chloride - name cation then anion
molecular: nonmetal and nonmetal: diphosphorous pentoxide - use prefixes
anions derived by adding H+ to an oxyanion are named by adding….
hydrogen or bi as a prefix
CO3-2 carbonate ion –> H2CO3 hydrogen carbonate/bicarbonate ion
deflection of particles between charged plates
if the particle is only slightly deflected then it has a large mass because heavier molecules are harder to move and linear momentum increases
what happens when metal carbonates decompose?
metal carbonates decompose to form metal oxides and carbon dioxide
what happens when metal chlorates decompose?
metal chlorates decompose to form metal chlorides and O2
what happens when hydrocarbons combust?
hydrocarbons combust in air to form CO2 and H20
molar mass
grams/mol
MM to formula weight
MM in grams is equivalent to formula weight in amu
empirical vs. molecular
empirical formula is the smallest whole number ratio combination - to get the molecular formula: molecular weight/ empirical formula weight to get a whole # multiple
combustion analysis
you get a certain amount of CO2 and H20 and you find H and C from it and possibly another compound
limiting reactant
USE ICE CHARTS
percent yield
actual/theoretical (actual is the amount of product actually obtained, usually given to you)
avogadro’s number
6.022x10^23 atoms
molarity
moles of solute/liters of solvent
