Chem 1: Ch 5-9 UMT Dwyer Flashcards
Midterm I
Petrochemical
substance that is made from petroleum or other related substances such as coal or natural gas
Petroleum
a thick, flammable, yellow to black substance found in selected locations on earth, usualy in underground resevoirs; central to modern life in industrialized nations
water
clear, colorless, tasteless substance found almost everywhere on earth; essential to life support
petrochemical era
the period of time in which petrochemicals are used to manufacture products that are central to all aspects of life. generally agreed to have started inthe 1940s and is accelerating and continuing today
3 phases of matter
s, l, g
solid
constant shape and volume; vibration in a fixed position
liquid
variable shape (bottom of a container) and constant volume; touch one another & move around each other
gas
variable shape and volume (same as closed container); move independently, very widely spread
pure substance
one kind of matter, distinct and unue physical and chemical properties
mixture
sample of matter composed of 2 or more chemicals/substances; properties depend on relative amounts of parts
eg gin/water
element
a pure substance that cannot be decomposed into other pure substances by ordinary chemical means
compound
a pure substance that can be broken down into 2 or more pure substances by a chemical change.
Do NOT confuse element/compound with pure/mixture eg water is a pure compound that can be chemically separated into pure elemnts
physical properties
measurable and detecable by senses; eg water boils at 100*C
freezing point, boiling pt, density, color
physical change
new form of same substance
chemical properties
list of chemical changes possible; eg water reacts with sodium to form hydrogen, sodium ions, and hydroxide iions
chemcial change
old substance destroyed, new substance formed (eg hindenburg disaster)
homogenous
uniform appearance and composition throughout
heterogeneous
visibly different phases and/or different composition in a sample of matter
distillation
process of separating the components of a mixture by heating the liquid and collecting the gaseous components that sepearate formt he remainder of the liquid
separation of mix based on differences in volatility, speed of evaporation
element with lower boiling point evaporates first
3 major substances extracted from earth
petroleum, coal, natural gas
Pure substances that are compounds
water, sugar, baking soda, aspirin
pure elemental substances
gold, copper wire, lead fishing sinks
fractional distillation
The vapor enters the bottom fo the column and rises through the column, with the substances with the higher boiling points condensing back to the liquid state nearer the bottom of the columna and the lower-boiling liquids condensing higher in the column
cracking
less valuable fractions are subjected to a process called cracking- where the fraction is transformed, or cracked into gasoline
Macroscopic appearance… bubbles
the terms homogeneous and heterogeneous refer to the macroscopic appearance of a sample. a container fileld with ice and liquid water is hetergeneous in appearance but is also pure, as long as in both phases the water is pure
electrical charge
a property of matter that causes it to experienc a force when near other electrically chaged matter
2 types of charged matter
- attracted to the other type
2. same type repels the same type
Ben Franklin
proposed the hypothesis that the two types of charged matter resulted from an excess or deficiency of a single kind fo charge
Alessandro Volta
Italian Scientist- invented the first battery “voltaic pile” after learning that he itneraciton of brass and steel and a solution could cause a muscular contraction in a frog’s leg
Nicholson & Carlisle
used the current generated by a voltaic pile to decompose liquid water into hydrogetn and oxygen, finding that the volume of hydrogen produced was twice that of oxygen
Nicholson & Carlisle’s discovery led to…
Law of Combining Volumes
Law of Combining Volumes
the volume ratios in which gases react are always a ratio of small, whole numbers
Avogadro’s Hypothesis
explains the Law of Combining Volumes by proposing that equal volumes of gases contain equal numbers of molecules
led to distinguishing btwn monoatomic and diatomic elements based on the nature of the combining volumes
Monoatomic
Adjective
Consisting of one atom.
Monovalent.
Diatomic
Adjective
Consisting of two atoms.
“plum pudding” model
By 1911 the components of the atom had been discovered. The atom consisted of subatomic particles called protons and electrons. However, it was not clear how these protons and electrons were arranged within the atom. J.J. Thomson suggested the”plum pudding” model. In this model the electrons and protons are uniformly mixed throughout the atom:
Rutherford “gold foil” experiment
Rutherford tested Thomson’s hypothesis by devising his “gold foil” experiment. Rutherford reasoned that if Thomson’s model was correct then the mass of the atom was spread out throughout the atom. Then, if he shot high velocity alpha particles (helium nuclei) at an atom then there would be very little to deflect the alpha particles. He decided to test this with a thin film of gold atoms. As expected, most alpha particles went right through the gold foil but to his amazement a few alpha particles rebounded almost directly backwards.
These deflections were not consistent with Thomson’s model. Rutherford was forced to discard the Plum Pudding model and reasoned that the only way the alpha particles could be deflected backwards was if most of the mass in an atom was concentrated in a nucleus. He thus developed the planetary model of the atom which put all the protons in the nucleus and the electrons orbited around the nucleus like planets around the sun.
Rutherford “gold foil” experiment
- discovered the proton via further experiments with alpha particles
What are the products when Nitrogen is bombarded with alpha particles?
protons are one product of the reaction
Oxygen
Who discovered the neutron?
many contributed, but it was Chadwick who ultimately conducted the highest quality experiments and interpreted the results correctly
What are the products when Berryllium is bombarded with alpha particles?
A particle with no charge and a mass similar to a proton
carbo
Electron
e or e- negative charge mass= 9.109 x 10%-28g 0.000549 u ~0 discovered in 1897 by Thomson
Proton
p or p+ positive charge mass= 1.673 x 10^-24 1.00728 u ~1 discovered in 1919 by Rutherford
Neutron
n or n0 zero charge mass= 1.675 x 10^-24 1.00867 u ~1 discovered in 1932 by Chadwick
Curvature of track is directly proportional to
the charge divided by (mass x velocity)
eg cloud chamber
Cloud Chamber
- charged particles leave a track
compare the mass of a proton and an electron
if the mass of a proton =1 then comparatively, the mass of an electron is 1/2000
What modern modifications have been made to Dalton’s Atomic Theory?
- atoms are made up of even smaller subatomic particles
2. atoms of an element can vary in mass
Isotope
atoms of the same element with different #s of neutrons and thus different masses
eg H can have 0, 1 or 2 protons
Nuclear symbol- what are the top and bottom numbers to the left of the chemical symbol?
the top left is the mass number, the bottom left is the atomic number
eg an Argon with 40 as the mass # is called Argon-40
mass number
protons + # neutrons
atomic #
of protons
1 atomic mass unit (u) is defined as
1/12 the mass of a carbon-12 atom
also know as…
amu
u
Dalton
6.02 x 10^23 u = ? g
1g
Atomic mass
the average mass of the naturally occurring isotopes of an element, accounting for the relative abundance of each isotope
Periodic Table
arrangement of elements according to atomic number left to right with elements with similar reactivities in columns. Each box in the periodic table has 3 items. The top most number isthe atomic #, the # of protons in atoms of that element. The centered symbol is the chemical symbolused to represent the element. The bottom # is the atomic mass of the naturally occurring isotopes of the element.
Period
horizontal rows, numbered 1 (top) to 7 (bottom). usually not printed
Group
vertical columns of elements with similar reactivity
U.S. numbering for Groups: “tall” columns are labeled A, and “ditch” columns are labeled B. The A groups are numbered 1-8 from left to right. The B groups are numbered 3-4-5-6-7-8-8-8-1-2
Main group elements
U.S. A groups
Transition elements
U.S. B groups
stair step line
separates the metals on the left from the nonmentals on the right
Modern defn of chemistry
the study of particles as large as molecules and as small as the subatomic particles proton, neutron, and electron
Modern defn of biochemistry
the science that starts at the small end with molecules of biological relevance and continues up in size to the level of cells
Chemical Nomenclature
the system by which substances are named
IUPAC
The International Union of Pure and Applied Chemistry, the committee that recommends official names for all substances
Elements that occur as diatomic in nature
H2, N2, O2, F2, Cl2, Br2, I2
Horses Need Oats For Cl ear Br own Iz
Polyatomic molecules
(many atom)
Phosphorus P4
Sulfur S8
Physical states of elements at 25*C and 1 bar…
Most are solids
11 gases: All 6 elements in Group 8A, H2, N2, O2, F2, Cl2
2 liquids: Hg, Br2
Binary Molecular Compound
Compound formed by 2 nonmetals or a nonmetal and a metalloid (element that borders on the stair step line)
How do you name binary molecular compounds?
A. First word is the name of the first element with a prefix to indicate the # of atoms of that element in the molecule
B. Second word is the name of the second element, changed to end in -ide, also with the appropriate prefix
Prefixes & the number of atoms they indicate
mono = 1 di = 2 tri = 3 tetra = 4 penta = 5 hexa = 6 hepta = 7 octa = 8 nona = 9 deca = 10 if the compound is binary, then it ends in -ide
How do u identify an isotope?
By its mass number, A, the total # of protons and neutrons in the nucleus
A = Z + N
Interpolation
Predicting something within the range of your data
Extrapolation
Predicting something beyond the range of your data
Why r some atomic masses of elements inthe periodic table in parantheses?
They are radioactive, and there is no atomic mass in the sense that we have defined it. Instead, parantheses enclose the mass # of the most stable isotope
1 u = ?g
1.66 x 10 ^-24 g
7 diatomic elements
H2 N2 O2 F2 Cl2 Br2 I2
Polyatomic molecules
Phosphorus P4
Sulfur S8
Physical states of elements at 25*C
Most are solids
11 gases (group 8A) H2 N2 O2 F2 Cl2
2 liquids Hg Br2
Noble gases
Group 8A He (g) Ne (g) Ar (g) Kr (g) Xe (g) Rn (g)
Binary molecular compound
Formed by 2 no metals or a nonmetal and…
Metalloids
Border stair line
How do you name a binary molecular compound?
- First word…
Exceptions to binary molecular compound nomenclature rules
H2O is water… Not dihydrogen oxide
NH3 is ammonia …not nitrogen trihydride
Which 2 diatomic elements have different state symbols?
Br2 (l)
I2 (s)
Ion
Charged particle formed when a neutral atom or molecule loses or gains electrons
Cation
Pos
Loses or gains e-
Anion
Neg
When gains 1 or more electrons
Monoatomic ion
Ion formed from a single atom
Formula of a monatomic ion
Z
Name of a monatomic ion
Name of element followed by the word ion
Name of monatomic anion
-ide followed by the word ion
Memorize common ions
Especially the group B with more than one
& Exceptions:
Zn2+
Ag+
Naming acids
- ic -> -ate
- ous -> -ite
polyprotic acids
acids with more than one hydrogen ion
Oxoacids Nomenclature: Prefix/Suffix
per- -ic one more O -ic the -ic acid -ous one fewer O hypo- -ous 2 fewer O hydro- -ic NO O
naming intermediate ions of a polyprotic acid: eg H3PO4
H3PO4 phosphoric acid
H2PO4 - dihyrdogen phosphate ion
HPO4 2- hydrogen phosphate ion
PO4 3- phosphate ion
Ammonia v. Ammonium
NH3
steals H from somewhere & gets NH4+
in pure water and in solutions, can one water molec react with another?
yes and it forms ions
H20 + H20 -> H3O+ + OH-
hydroxide ion
this only occurs to a very, very slight extent
how do you name an ionic compound?
cation first then anion
hydrate
ionic compound that contains water molecules
Nomenclature: Element
Name; Formula
Name of element
Symbol of element; exceptions: H2, N2, O2, F2, Cl2, Br2, I2
Nomenclature: Compounds made up of 2 nonmetals
Name; Formula
- First element in a formula followed by second, changed to end in -ide, each element preceded by prefix to show the number of atoms in the molecule
- Symbol of 1st element in name followed by symbol of second element, with subscript to show number of atoms in molecule
Nomenclature: acid
Name; Formula
Most common: middle element changed to end in -UC
One more oxygen than -ic acid:add prefix per- to name of -ic acid
One fewer oxygen than ic acid: change ending of -ic acid to -ous
2 fewer oxygens than -ic acid: add prefix hypo- to name of -ous acid
No oxygen: prefix hydro- followed by name of 2nd element changed to end in -ic
H followed by symbol of nonmetal followed by O (if necessary), each with appropriate subscript.
Memorize: Chloric acid: HClO3 Nitric acid: HNO3 Sulfuric acid: H2SO4 Carbonic acid: H2CO3 Phosphoric acid: H3PO4
Nomenclature: monatomic cation
Name; Formula
Name of element followed by ion; if element forms more than one monatomic cation, elemental name is followed by ion charge in Roman numerals and in parentheses
Symbol of element followed by superscript to indicate charge
Nomenclature: monatomic anion
Name; Formula
Name of element changed to end in -ide
Symbol of element followed by superscript to indicate charge
Nomenclature: polyatomic anion from total ionization of oxoacid
Name; Formula
Replace -ic in acid name with -ate, or replace -ous in acid name with -ite, followed by ion
Acid formula without hydrogen plus superscript showing negative charge equal to number of hydrogens removed from acid formula
Nomenclature: polyatomic anion from step-by-step ionization of oxoacid
Name; Formula
.
Nomenclature: other polyatomic ions
Name; Formula
.
Nomenclature: ionic compound
Name; Formula
.
Ch9: A3
Explain how an anion can behave like an acid. Is it possible for a cation to be an acid?
An anion or cation that contains an ionizable hydrogen, such as HSO4- and NH4+ can lose the hydrogen as thus behave like an acid.
Nomenclature: hydrate
Name; Formula
.
