Chem-Phys1 Flashcards
Scientific Notation
method of writing numbers that takes advantage of powers of 10: significand and exponent
Significand
absolute value in the rang 1-10, cant be 0
Converting #s to Scientific Notation
move the decimal point until the signficand is bigger than or equal to 1 and less than 10
What is 34,600, 0.0003201, 1.10 and 525,600 in scientific notation?
34,600, 3201, 1.10, 525,6
When rounding two numbers containing decimals, in which direction should each number for multiplication go?
adjust the two decimal points in opposite directions: as one moves up, move the other down
When rounding two numbers containing decimals, in which direction should each number for division go?
adjust the two decimal points in the same direction
Scientific Notation Tips
- Count all numbers between the first nonzero digit on the left and the last nonzero digit on the right
- any 0s to the left of the first nonzero is consider NS
- 3,490 has 3 sig, 3,490.4 has 4- watch for decimal places
Rounding of Sig Figs
round to the number of sig figs that is the same as the least number of sig digits in any of the factors given
X^0 =
1
X^A x X ^B =
X^(A +B)
X^A/ X^B =
X^(A-B)
(X^A)^B =
X^ (A x B)
(X/Y)^A =
X^A/ Y^A
X^-A
1/X^A
X^(A/B)
square root with B on the outside of X^A
Perfect Squares Example: square root of 180 =
square root of 4 x square root of 9 x square root of 5 = 2 x 3 x square root of 5 = 6 square root 5
square root of 2
1.414
square root of 3
1.732
LogA 1=
0
LogA A=
1
Log A x B =
Log A + Log B
Log A ^ B
BLogA
Log (A/B)
Log A - Log B
Log (1/A)
-log A
Henderon-Hasselbalch equation
pH= pKa + Log [A-/HA]
(a + b) ^2
a^2 + 2ab + b
Log (n x 10^m) = log (n) + log(10^m)
= m + log (n)
values of sin, cos and tan range
sin and cos range from -1 to 1, tan ranges from - infinity to positive infinity
inverse of sin, cos and tan used to find
angle of interest
0 degrees sin, cos and tan values
sin = 0, cos = 1, tan = 0
30 degrees sin, cos and tan values
1/2, root 3 over 2, root 3 over 3
45 degrees sin, cos and tan values
root 2 over 2, root 2 over 2, `
60 degrees sin, cos and tan values
root 3 over 2, 1/2, root 3
90 degrees sin, cos and tan values
1, 0, undefined
180 degrees sin, cos and tan values
0, -1, 0
Fahrenheit equation from C
F= 9/5C +32
Kelvin equation with C
K= C +273
Conversion between metric prexies is accomplished by what?
by muiltpication or divine by appropriate power of 10. For example, millimeters (10^-3) to kilometers (10^3), multiply by 10^-6
scientific method
set of steps that defines the appropriate order of event to structure and carry out an experiment
scientific method steps
generate testable question, gather data, hypothesis (if-then and testable), collect new data (experimentation or observation), analyze data, interpret data, publish, verify results
FINER method
method to determine whether the answer to ones question will dd to the body of science knowledge in practical way and within reasonable period
FINER method 5 questions
- is research study going to be feasible? - obtain necessary supplies, financial or time restraints, gather enough subjects
- Do other scientists find this question interesting?
- Is this question novel?– gain any new knowledge?
- Would the study obey ethical principles?
- Is the question relevant outside scientific community?-more important if impact more people
errors or biasing during publication are most likely to affect which stages of scientific method?
affect the quality of future experimentation since their is a flawed research base and therefore subsequent hypothesis will be flawed
basic science research
experimenter has so much control because done in lab not on people
controls
acts as a method of verifying results
postitive controls
ensure a change in the DV when it is expected
administer HIV test to HIV positive people
negative control
ensure no change in the DV when no change is expected – placebo effect (observed change when people given a sugar pill)
administer HIV test to HIV negative people
positive and negative controls create ___
the upper and lower bounds
IV
manipulate
DV
measure or observe
causal relaionships
if the change in the IV always precedes the change in DV< and the change in the DV does not occur in absence of intervention, then causal
basic science researcher errors
experimental bias is minimal, except if have faulty hypothesis, failing to publish results that may contradict hypothesis
instrument error
may affect accuracy, precision or both
accuracy
also called validity- ability of an instrument to measure a true value
precision
or reliability - ability of an instrument to read consistently or within a narrow range
accurate but not precise
persons weight between 150-190 pounds
inaccurate but precise
129 and 131 pounds, but rlly 140 pounds
inaccurate tools (but precise) produce
systematic error/bias
controls purpose
controls experimental help establish casualty by demonstrating that the outcome does not occur in absence of the intervention. controls are suet keep the manipulation of diff systems as similar as possible, or as known standard against which to judge an experimental manipulation
human subjects research
experimental control is low (because of ethics) and relationships are weaker
experimental and observational studies
randomization
control for differences between subject groups in biomedical research
placement of each subject into a control group or treatment group
coin toss random
blinding
researchers have no information about which group the subject is in
single blinded experiments
only the patient or assessor (person who makes measurement on patient) is blinded
double blinded experimetns
both investigator, assessor and patient do not know subjects group
confounding variables
internal validity decreases, alternative explanations for the data
gender, age, lifestyle things, etc
types of questions: binary
yes or no, better or worst
continuous variables
on a range- percent improvement, weight loss
categorical variables
SES, where do you live
observational approach
cohort, cross sectional or case -control studies
no experiment/manipulation
no causality
cohort studies
subjects sorted into groups based on differences in risk factors (exposures) and then assessed at various intervals to determine how many subject sin each group had a certain outcome
count how many people get lung cancer with 20 people who smoke and 20 people who dont smoke over 40 years
cross sectional studies
attempt to categorize patients into different groups at a single point in time
prevalence of lung cancer in smokers or nonsmokers at a given point in time
case control studies
look at how many subjects have a particular outcome to not, and then look backwards to see how many subjects in each group had exposure to a certain risk factor.
100 patients with lung cancer and 100 people without lung cancer are assessed for smoking hisotry
Hill’s criteria
observed relationships components that increase the likelihood of causality in the relationship
described as correlation for any observational study
dose response relationship
as IV increases, increase in response
consistency
relationship found in many settings
plausiblity
reasonable mechanism for the IV to impact the DV with support by literature
specificty
change in DV is only produced by associated change in IV
coherence
new data and hypotheses are consistent with the current state of scientific knowledge
systematic error bias
does not impact precision, but skews data in one direction or another
bias
a result of flaws in the data collection systematic error (unidirectional) that occurs when selected subjects or collecting data
confounding
error during analysis
selection bias
subjects used for study are not representative of target population
people who volunteer vs. people who dont volunteer
gender in study, age
detection bias
educated professionals using their knowledge in an inconsistent way. because prior studies indicate there is a correlation, researchers will expect to find one
Hawthorne effect
or observation bias, behavior of the study participants us altered because they recognize they are being studied
want to look good- exercise more than normal
confounding
data analysis error
incorrect relationship is characterized
third party variables
alt explanations
causality 3 things
temporal precedence, correlation (associated) and internal vliaidty (no 3rd v)
observational relationships
no manipulation of the subjects environment. less conclusive and more subjective than experimental research
ethics
beneficence, nonmalefience, autonomy, justice
beneficence
obligation to act in the pt best interest
nonmalefience
obligation to avoid treatnetrs or intverntions in which harm would outweigh benefits
autonomy
responbsity to respect patients decisions and choices about own healthcare
justice
responsibility to treat similar patients with similar care, and distribute healthcare fairly
Belmont report
respect for persons, justice and benfieince
respect for persons
honesty between subjects and researcher
informed consent - know al the Risks, benefits, goals to make a knowledgeable decision if want to participant
no coercive influence
can withdraw consent at any time
IRB
protection against unethical studies
vulnerable people
prisoners, women and children have special protection with research
justice
morally relevant differences - diff between individuals that are ok to treat them differently (age)
NOT ok: race, ethnicity, sexual oretination- treat the same
important in selection subjects and executing research
no harm to any group
beneficence
intent to cause a net positive change for both the study population and general population, minimizing potential harms - least invasive, painful or traumatic way
catheter or finger poke - equipoise- finger poke Is superior
compensatory influence
no impact the decision to participant, coercive influence is which subject loses autonomy to make the decision
population
complete group of every individual that satisfies that attributes of interest
humans- 7 billion people
American F between 18-20 YO
parameter
information that is calculated using every person in a population
sample
making generalizations about populations based on sample data
any group taken from a population that does not include ALL the people
random samples!! to ensure represenatative
low generalizabilty
narrow conditions for sample selection that do not reflect target population
statistically significant
not as a result of random chance
internal validity
tendency for same experiment to produce the same results when repeated and provides support for causality
external validity
ability to take the info generated and apply it to larger group. also called generalizabilty
small sample isses
subject to more random variation than larger samples. if only 1 person is selected, may be an outlier. If larger sample, an outlier has less of an effect on results
clinical significance
impact patients - notable change in health status as a result of research intervention
protons
found in the nucleus
+1 charge
atomic number of an element= number of protons (Z)
all oxygens have the same amount of protons (8)
neutrons
neutral, no charge. mass number (A)- sum of the protons and neutrons mass (which makes up most of the atoms mass) a given element can have a variety of neutrons, so have different mass number (same atomic number tho)
isotopes
atoms with the same atomic number but different mass numbers
determined by neutrons
A/Z X
mass number/atomic number Element
electrons
-1 charge.
very small mass.
move around nucleus at varying distances, corresponding to varying levels of electrical potential energy.
electrons closer to nucleus have
lower energy levels
electrons farther from nucleus (higher electron shells) have
higher energy! strongest interactions with the surrounding environment and weakest interactions with the nucleus. Called valence electrons- more likely to bond with other atoms since dont feel nucleus electrostatic pull.
determine reactivity of the atom
donating or sharing increases stability in reaching highest energy level
positively charged atom
cation
negatively charged atom
anion
charge is determined by
electrons
atomic number is determined by
protons
heaviness of an element
atomic weight is constant for a given element, atomic mass or mass number vary from 1 isotope to another (because neutrons)
atomic mass
mass of 1 proton= 1 amu= mass of 1 neutron
atomic mass of an atom is nearly equal to
its mass number in amu, in sums of protons and neutrons
atomic weight
the weighted average of these different isotopes of an element
represents both the mass of the average atom of that element in amu and the mass of 1 mole of the element in grams
half life corresponds with
stability and proportions of these isotopes
a mole is
a number of “things” (atoms, ions, molecules) that equal to Avogadros number (6.02 x 1023)
example of atomic weight
atomic weight of C is 12.0 amu, which means that the average carbon atom has a mass of 1 amu and 6/02 x 10^23 C atoms have a combined mass of 12 g.
Planck relation
the energy of a quantum
E= hf
h= Plancks constant = 6.626 x 10^-34 J x s
f= frequency of the radiation
angular momentum
L=mvr
kinetic energy
1/2 m v ^2
Bohr Model
angular momentum
angular momentum
L = nh/2 pi
n= quantum number (+ integer)
h=plancks constant (6.626 x 10^-34)
angular momentum changes with regards to quantum number
energy of the electron equation
E = -(R sub H)/n^2)
R sub H = Rydberg unit of energy= 2.18 x 10^-18 J/electron
energy of electrons changes with regards to quantum number
the energy of the electron increases- becomes less negative- the farther out from the nucleus it is located (increasing n)
electrons jump when
the amount of energy exactly is equal to the difference between 1 orbit and another
like a staircase, not a ramp
the orbit with the smallest, lowest energy radius
ground state (n=1)
excited state
when an electron moves to a sub shell of higher than normal energy - an orbit with a larger radii
Bohr model importance
explain atomic emission and absorption spear of atoms
electrons can be excited with the addition of
heat or energy forms, bu brief and electrons will return to ground state, leading to emission of energy in the form of photons. these energy transition do not form a continuum, but rather are quantized to
electromagnetic energy of photons equation
E= hc/lambda h= planks constant (6.626 x 10^-34) c= speed of light in a vaccum (3.00 x 10^8 m/s) lambda= wavelength of the radiation
line spectrum
each line on the emission spectrum (frequency of light) corresponds to a specific electron transition. Because each element can have its electrons excited to a diff set of distinct energy levels, each possess a unique atomic emission spectrum (fingerprint for element)
Lyman series
hydrogen emission lines corresponding to transition from energy levels n > 2 to n= 1
Balmer series
hydrogen emission lines corresponding to transition from energy levels n >3 to n=2
4 wavelengths in visible region
Paschen series
Hydrogen emission lines corresponding to transition from energy levels n >4 to n=3
the energy associated with a change in the principal quantum number from a higher initial value ni to lower final value nf is equal to
the emerge of the photon predicted by plancks quantum theory.
Combining Bohr and PLancks calucations
E= hc/lambda= R sub H [1/ni^2 - 1/nf^2
the energy of the emitted photon corresponds to the difference in energy between higher energy initial state and the lower energy final state
absorption spectrum
when an electron is excited to a higher energy level, it must absorb exactly the right amount of energy to make that transition. energy absorption at a specific wavelength to exciterse electrons of a particular element.
each element has a unique
emission spectrum and absorption spectrum (correspond together because the difference in energy between levels remains unchanged )
absorb energy in forms of light and emit in forms of light
Bohr’s model failed to
explain the structure and behavior of atoms containing more than 1 electron (only did Hydrogen)
did not take into account repulsion between many electrons surrounding the nucleus.
difference between Bohr’s model and modern quantum mechanical model
Bohr thought that electrons followed a clear defined circular pathway or orbit a fixed distance from the nucleus , whereas modern quantum mechanics showed that electrons move more rapidly and are localized within regions of space around the nucleus (orbitals). Impossible to determine where an electron is exactly at any point in time.
Heisenberg Uncertanity principle
it is impossible to simulateouly determine, with perfect accuracy, the momentum, and the position of the electon
Pauli exclusion principle
no two electrons In a given atom can possess the same set of 4 quantum numbers (n/l/ml and ms)
energy state
the position and energy of an electron described by its quantum number. the value of n limits l which limits ml
quantum number give info about
size, shape and orientation of the orbitals.
quantum number n
principal quantum number. used in Bohr’s model and can take on any + integer number. the larger + number, the higher the energy eve and radius of the electron shell.
maximum number of electrons within a shell
2n^2
n- principle quantum number
the difference in energy between two shells decreases as the distance from the nucleus increases due to
the energy difference is a function of [1/n^2 - 1/nf^2]
ex. difference between n=3 and n=4 shells are 1/9 - 1/16 is less than the difference between n=1 and n=2 shells (1/1- 1/4).
azimuthal (angular momentum) quantum number- l
refers to the shape and number of sub shells within a given energy level (shell). important implications with chemical bonding and bond angles.
the value of n limits l
for any given value of n, the range of possible values for l is 0 to (n-1).
ex. n==2 sub shells
l can be 0 or 1.
spectroscopic notation
principal and azimuthal quantum numbers principal quantum number is a number (1, 2) and l turns into letters l=0: s l= 1: p l=2: d 1=3: f example. n=4 and l=2 =4d
the energies in the sub shells increase
with increasing l values
magnetic quantum number
ml. specifies the particular orbital within a sub shell where an electron is most likely to be found at a given moment in time. each orbital can hold a maximum of 2 electrons.
integers between 1 and -1,including 0.
s sub shells, with l=0, limits ml to 0 because there is a single value o fm1 and only 1 orbital in s shells.
the p sub shell, l=1, ml can be -1, 0 or 1, because there are 3 values for m1 and three values in the p sub shell.
d sub shell has 5 orbitals (-2 to +2) and f has seven orbitals (-3 to 3)
the shape of the orbital, like the number of orbitals is dependent on
the sub shell in which they are found in: s shells are spheres, p shells are dumbbells
as atomic number increases, so does number of electrons
2p contains 3 orbitals. If each orbital contain 2 electrons than 6 electrons can be added during the course of filling 2p orbitals.
spin quantum number
ms. spins in +1/2 or -1/2. whenever two electrons are in the same orbital, they have opposite spins- refereed to as paired. electrons in diff orbitals with the same ms values are parallel spins.
electron configurations
the pattern by which subshells are filled, number of electrons within each energy level and sub shell is designated by this.
use spectroscopic notation, first number denotes energy leveladn the letter is sub shell and subscript is number of electrons in subshell.
2p^4- 4 e- in the second p sub shell of the second energy level (1s and 2s are indicated to be full)
Aufbau principle
electrons fill from lower to higher energy sub shells and each sub shell is completed before electrons begin to enter the next one.
n+ 1 rule
rank sub shells by increasing energy. the lower the sum of the values of the first and second quantum number, n+ 1, the lower the energy of the sub shells.
lower n value, fill with electrons first.
Hunds rule
in sub shells that contain more than 1 orbital, such as the 2- sub shell with 3 orbitals. This rule states that within a given sub shell, orbital are filled such that there are a max number of half filled orbitals with parallel spins. Would prefer own orbital before forced to double up with another. due to repulsions.
half filled and fully filled orbitals have lower energies and higher stability than other states
chromium electron configuraton
Ar 4s^23d^4 but moving 1 e- from 4s to 3d all’s 3d to be half filled and be Ar4s^1 3d^5
how many electrons each orbital can hold
s- 2
p- 3
d- 10
f-14
copper electron configuraton
Ar 4s^13d^10 rather than Ar4s^23d^9 as full d sub shell outweighs the cost of moving an electron out of th 4s sub shell.
never observed In p shells- not worth loss of stability.
paramagnetic
unpaired electrons in atoms will oreint their spins in a ligament with a magnetic field and the material is weakly attracted to it.
diamagnetic
toms that have only paired electrons will be slightly replied by magnetic field
valence electrons
outermost energy shells electrons- easily removed and available for bonding
IUPAC step 1
identify the longest carbon chain containing the highest-order functional groups, also called the parent chain, If there are two or more chains of equal length, then then the more substituted chain gets priority as the parent chain.
IUPAC step 2
number the chain. Number 1 is closest to the highest priority functions group. If all the same priority, numbering the chains should make the numbers of the substituted carbons as low as possible
oxidation state
the more oxidized the carbon is, the higher priority it has in the molecule. oxidation state increases with more bonds to the herteroatoms (any atom but H and C) and decreases with more bonds to H.
rings- double and triple bonds
everything is the same- numbering from greatest sub. if there is a tie between assigning priority in a molecule with a double and triple bond, double bond takes precendence (not normal)
IUPAC step 3
name the subsitutuents. Substituents are functional groups not apart of the parent chain. Name will be placed at the start of the cmpd name as a prefix, followed by name of the longest chain. only the highest priority functional groups will determine the suffix for the cmpd and must be apart of the parent chain.
CH3, CH3Ch2, CH3CH2CH2
methyl, ethyl, n-propyl
if there are multiple subsitutents of the same type, use these prefixes:
di-,tri-, tetra0, etc.
IUPAC step 4
give C number designation and use prefixes
2,3-dimethyl
IUPAC step 5
complete the name. alphabetical order sub!!! prefixes like di-, tri- are ignored when alphabetizing. numbers are separated by commons, and form words with hyphens.
example- 4-ethyl-5-isopropyl-3,3-dimethyloctane
hydrocarbons
only C’s and H’s
alcohols
C’s, H’s and OH!
alkane
simply hydrocarbons with the formula CnH2n+2.
methane- 1C
ethane-2C
propane-3C
butane-4C
meth isn’t ethical or propiate BUT
pent, hex, hept, oct, non, dec, undec, dodec
halogens
common sub on alkanes. alkyl halides are indicated by prefix: fluoro, chloro, bromo, iodo
-ene, -yne
double and triple bonds. usually is named like a sub and numbered by lowest C.
example: 2-butene, or but-2-ene
1,3-butadiene
alcohols
named by replacing -e at the end of the name with -ol. -OH gets the lowest possible number, even when there is a multiple bond present due to its higher oxidation state. If alcohol is not highest sub group, then it is called hydroxy-.
ex. ethanol
5-methyl-2-heptanol
hept-6-en-1-ol
alcohols with 2 hydroxyl gross are called diols or glycols
and are indicated with the suffix -diol. ex. ethane-1,2-diol has hydroxy group on each C. diol is added at end.
diols with hydroxyl groups on the same carbon
geminal diols
diols with hydroxyl groups on adjacent carbons
vicinal diols
2-propanol
isopropyl alchol
ethanol
ethyl alcohol
aldehydes and ketones both contain a
carbonyl group, C=O. with no leaving groups connected to the carbonyl carbon- only connected to the carbon chain or aldehydes with a H. if there is a higher priority group, name ketone and aldehydes with prefix oxo- or keto- for ketones only
aldehydes
chain terminating- end of parent chain. generally attached to carbon 1 bc takes priority. Replace -e with -al.
ex. butanal
ketones
found in the middle of carbon chains. replace -e with -one. give lowest possible number
ex. 2-penanone
methanal, ethanal, propanal
formaldehyde, acetaldehyde, propionaldehyde.
propanone
always ketone on C2.
acetone
carbon adjacent to the carbonyl carbon
alpha. successive C’s are beta, gamma, and delta. on ketone, both C’s are considered alphas in the carbonyl carbon
ketones and aldehydes both take precedence over:
alcohols and hydrocarbon chains, and the functional group that is the highest priority determines the suffix. aldehydes usually do suffix because they are terminating
carboxylic acids
both a carbonyl group (C=O) and a hydroxyl group (-OH) on a terminal carbon. terminal functional groups like aldehydes. Oxidized carbon!!! (3bonds to it)so HIGHEST PRIORITY GROUP EVER! replace -e with -oic acid.
formic acid, acetic acid, propionic acid
methanoic acid, ethahnoic acid, propanoic acid
esters
common carboxylic acid dervitaitves. hydroxyl group (-oh) is replaced with an alkoxy group (-OR, where R is a hydrocarbon chain). based on carboxyl naming. first term is how many C are in the hydrocarbon chain
ethyl, methyl, propyl, etc.
second term is the parent acid, with -oate replacing -oic acid.
methyl butanoate
amides
carboxylic acid derivative. the hydroxyl group is replaced by an amino group (n containing group). N can be bonded to 0, 1 or 2 alkyl groups (C, H). Suffix is amide. Sub are started with capitol N in front to indicate they are bonded to N- not numbered and prefixed.
N-ethyl-N-methylbutanmide
anhydrides
carboxylic acid derivative (from 2 actually and water is removed. Cyclic molecules. replace acid with anhydride in the name of the corresponding carb acid if the anhydride is formed from only one type of carb acid. if the anhydride is not symmetrical, both carb acids are named without suffix acid and before anhydride is added.
ex. ethnoic propanoic anhydride
ethnoic anhydride
functional group proriorty list
carb acid (oic acid), anhydride (anhydride), ester (oate), amide (amide), aldehyde (al), ketone (one), alcohol (ol), alkene (ene), alkyne (yne), alkane (ane)
suffix ^^^^
mendelevs table was arranged by atomic weight, but modern periodic table is arranged by
atomic number (number of protons in an element)
A elements
representative elements- groups 1A-VIIIA- valance elcectrons in the orbitals of either s or p sub shells.
B elemtns
nonrepresenative elements (transition elements - valence electrons in the s and d subsehlls) and the lanthanide and actinide series (s and f sub shells)
metals are
lustrous (shiny), high MP and densities, malleability (can be deformed without breaking), ductility (pulled into wires),low EN, large atomic radius, small ionic radius, low ionization e, low electron affinity, good conductors - two or more osdiations states - loosely held to atoms
nonmetals are
upper right side of table. no metallic luster, high ionization energy, electron affinity, EN and small atomic radii and large ionic radii. poor conductors cuz cant give up e-.
metalloids
both metals and nonmetals.brittleness but good conductivity.
effective nuclear charge
a measure of the net positive charge experienced b the outermost electrons. pull toward the center. increases from L to R of the periodic table . Zeff. constant in given group.
principal quantum number
down the elements of a given group, increases. valence electrons are separated from the nucleus.
octet rue
tend to be most stable with 8 electrons in valence she
atomic radii
equal to 1/2 the distance between centers of 2 atoms in contact with one another. decreases from L to R across a period. atomic radius increases down a group
ionic radii
metals lose e- and become +, nonmetals gain e- and become -. metalloids go based on side they fall on. nonmetals close to metalloid line possess a larger ionic radius than counterparts. metals close to metalloid line have more ee- to lose, and experience a less drastic reduction in radius during ionization.
ionization energy
energy required to remove an electron from gas/- input of heat- endothermic. high Zeff, more close to nucleus, harder to remove. increases from L to R and bottom to top.
electron affinity
energy dissipated by gas species when it gains an electron . opposite of ionization E. exothermic process. the stronger the electrostatic pull (higher Zeff) between the nucleus and valence e-, greater the E release will be when the atom gains an e-. increases across period from L to R, decreases from top to bottom.
Electronegativity
measure of thr attractive force that an atom will exert on an electron in chemical bond. greater EN, more it attracts e- within that bond. lower ionization E, lower EN. first 3 nobel gases are exceptions.
high reactivity to water
groups 1 and 2
six valence electrons
6 and 16 groups
contain at least 1 metl
groups 1-15
multiple oxidation states
all groups. notably 3-12 (transition metals)
- oxidation states
all groups, notably 14-17 (nonmetals)
possess a full octet in neutral state
group 18
group 1
alkali metals. Zeff low. low densities. low ionization E, low electron affinity, low EN
alkaline earth metals
group 2. slightly higher effective muscular charge and slightly smaller atomic radii.
active metals
group 1 and 2- so reactive
chalcogens
group 16/ eclectic group of nonmetals and metalloids. reactive. 6 e- in valence shell and small atomic radii and large ionic radii. Ozugem
halogens
group 17 are highly reactive with 7 e- valence. want to complete octet. gas to solids and liquids. high EN and electron affinity
noble gases
group 18. inert gases. limited reactive because 8 valence e-. low BP
transition elements
groups 3-12. metals with low electron affinity, low ionization E, low EN, high MP and BP . malleable and good conductors. ‘different oxidation states because capable of losing diff #s of electrons from the s and d orbitals.
if a newton is the product of a kilogram and m/s, units for pounds are
Force will obey the sam relationship with mass and ace elation, so always m/s. one pound = slightly x ft/secons square
smallest to largest
angstrom, cm, inch, foot, mile
scalars
numbers that have magnitude only, on direction- distance, speed, energy, pressure and mass
A + B and B + A
vectors look the same - no difference in R
A- B and B-A
have the same R but in opposite directions
scalar is calculated by 2 vectors by using the dot product
A x B = ABcos theta
vector is calculated by 2 vectors by using the cross product
A x B = ABsintheta
displacement
has magnitude and direction- net change from initial to final direction
velocity
rate of change of displacement over time. speed is rate of distance.
insanteous speed of an object will always be equal to the magnet of the objects
instaneous velocity, which measures the average velocity as the change in time approached 0
average velocity
displacement vector over time- vector
average speed
scalar. the rate of total distance traveled over a change time
v= d/t
equation
total distance traveled can Never be less than the total displacement
because displacement is the most direct route.
displacement
velocity over time
Equation - gravtional force
Fg= Gm1m2/r^2 G= 6.67 x 10^-11
friction equation
Friction = muFn
Weight equation
Fg= mg
acceleration equation
a= v/t
direction of the friction force always opposes
movement.
if there is no net force acting on an object,
then the objects not expericnign an acceleration and has a constant velocity
Force on you by earth and force of you on earth is
equal! forces are reipiorcal in magnitude.
Newtons first law
F= ma= 0. A body either at rest or in motion with constant velocity will remain that way unless a net force acts on it
Newtons second law
F= ma. An object of mass m will accelerate when the vector sum of the forces results in some nonzero resultant force vector. Accleraiton results from sum of force vectors
Newtons third law
Fab= -Fba
to every action there is an equal opposite reaction. For every force exerted by A on B, there is an equal but opposite force on B on A
equations
V= Vo + at x= Vot + at^2/2 V^2= V^2o + 2ax x=vt Fc= mv^2/r
the only force in free fall and projectile motion
gravity
free fall
object falls with constant acceleration, without air resistance. not reach terminal velocity. 9.8
projectile motion
2 dimensions, x and y. . objects in motion on earth experience force and accleriton due to gravity only in y axis, Vx remain constant.
greattes horizational displacement at angle
sin and cos are at 45
greatest vertical displacemnet at angle
launched vertically?
translational equilibrium
forces cause objects to move without any rotational. vector sm of all the forces acting on a object is 0, constant speed and direction
rotational equlibirium
occurs when forces are applied against an object to cause an object to rotate around a fixed point- torque
T= F x r- Frsintheta
sum of all torques is 0
equation
v= frequency x wavelength
period
number of seconds per cycle- T= 1/freq
angular frequency
measures in radians per second
= 2 pi frequency or 2pi/T
wave speed
is the rate at which a wave transmit the E or matter it is carrying. parodic of frequency and wavlength
frequnecy
measure of how often a waveform passes a given point in space. Hz.
angular frequency
same as frequency but in radians per second
equilibrium position
point with 0 displacement in an oscillating system,
amplitude
max displacement of a wave from equilibrium position
traveling waves
have nodes and antinodes that move with wave propganda
standing waves
defined nodes and antinodes that do not move with wave propgandtion
sound waves
longutidal waves
principle of supoerposition
when waves interact, the displacemnt of the resultant wave at any point is the sum of the displacement of the two waves interacting together
sound is produced by
mechanical vibrations generated by solid objects or fluids. sound is longutidal waves
ampltiud oof sound wave is related to its sound level
or volume. frequency of wave is related to its pitch
open both sides
wavelength = 2L/n
