PCAT Gen Chem

  1. Density equation
    D= m/v
  2. to go from g/cm3 to kg/m3 you need to..
    multiply by 1000
  3. to go from kg/m3 to g/cm3  you need to..
    divide by 1000
  4. 1=cm3 = 1 ___ = 1m3
  5. how many mls are in a m3
    1.00 x 106 = 1,000,000
  6. how many liters are in a m3?
    1000 L
  7. the angstrom is equal to _____m
  8. to do mole to grams you need to...
    multiply moles by the molecular weight
  9. to do grams to moles you need to
    divide the grams by the molecular weight
  10. avogadro's number is =
    6.02 x 1023
  11. Moles equation
    mass in grams / molecular weight
  12. all group IA elements have an oxidation number of..
  13. all group IIA elements have an oxidation number of..
  14. all group IIIB elements have an oxidation number of..
  15. Fluorine always has an oxidation number of...
  16. Oxygen almost always has an oxidation number of
  17. oxygen has a -1 oxidation state in ...
  18. hydrogen has an oxidation number of ____ when bonded to nonmetals
  19. hydrogen has an oxidation number of ____ when bonded to metals
  20. You can figure out the oxidation number of certain elements in a molecule by...
    summing the oxidation for all elements to zero then doing the math and dividing by the number of stoms to get the number
  21. in terms of their electron configuration F- and Ne are considered to be...
  22. transition metals are metals in the ___ block.
  23. the elements in the last column of the table are called ....
    noble gases
  24. The aufbau principle is when electrons occupy..
    the lowest energy orbitals available
  25. Hund's rule states that electrons in the same subshell occupy...
    available orbitals singly, before pairing up
  26. the pauli exclusion principle states that no two electrons...
    in the same atom can have the same set of four quantum numbers
  27. energy of a photon equation
    • E=h x f (h= plancks constant & f= frequency)
    • E=h x (c/wavelentgh)  (h= planck's constant & c= speed of light)
  28. the first quantum number is the _____ number
  29. the second quantum number is the _____ number
  30. the third quantum number is the _______ number
  31. the fourth quantum number is the _____ number
  32. the atomic number is the number of.....
  33. the mass number is the number of....
    protons + neutrons
  34. the mass number of an element can be written as...
    element - (mass#)
  35. mass number goes on what side of the element?
    top left
  36. atomic number goes on what side of the element?
    bottom left
  37. Protons minus electrons =
  38. charge goes on what side of the element?
    top right
  39. absorption is when you have a ___ energy change
  40. emission is when you have a ___ energy change
  41. value of planck's constant
    6.63 x 10^-34 J x s
  42. value of the speed of light
    3.0 x 10^8
  43. for electron configurations, use the boxes to count how high a level goes.

    s block goes to ___
    p block goes to ___
    d block goes to ___
    • 2
    • 6
    • 10
  44. when doing arrows for the electron configuartions, put in __ arrow(s) at a time
  45. when putting in arrows for electron configuration the first arrow is always point in the ___ direction.
  46. when putting in arrows for electron configuration the second arrow is always point in the ___ direction.
  47. Empirical formula uses the samllest number that gives the same ______ of atoms as in its corresponding molecular formula.
  48. to reduce a molecular formula, to an empirical formula...
    divide all the subscripts by their greatest common factor
  49. How do you find the percent composition by mass?
    • 1) find the molecular weight of the compound
    • 2)divide each elements mass multiplied by the numbers of atoms of that element by the compound mass
    • 3) multiply to get denominator to equal 100
    • 4) multiply by the same number on top
    • 5) convert to percent
  50. how do you get the empirical formula using moles?
    • 1) first get the moles of each element (in fractions)
    • 2) multiply moles together then simplify answer to lowest fraction
    • 3) those numbers are the subscripts
  51. the limiting reagent is...
    the reactive that we run out of first, limits how the reaction produces the product
  52. the stoichiometric number is..
    the subscript from molecular formulas
  53. the stoichiometric number gives what info?
    the ratios between constiuent atoms, NOT the bonding info
  54. in a stochiometric sense, what does the following equation "say"

    2Al + 6HCl -> 2AlCl3  + 3H2
    2 moles of Al react with 6 moles of HCl to form 2 moles of AlCl3 and 3 moles of H2
  55. periodic trends that begin with the letter "e" increase from...

    (electronegativity, ionization energy, electron affinity)
    left to right and bottom to top
  56. periodic trends that DO NOT begin with the letter "e" increase from....
    (metallic character, atomic radius, acidity)
    Right to left and top to bottom
  57. Electronegativity is...
    the chemical property describing an atom's ability to attract and bind to electrons.
  58. The atomic radius is...
    is one-half the distance between the nuclei of two atoms.
  59. Ionization energy is...
    the amount of energy required to remove an electron from a neutral atom in its gaseous phase (opposite of electronegativity)
  60. electron affinity is...
    ability of an atom to accept an electron
  61. metallic character is...
    how readily an atom can lose an electron
  62. acidity is ...
    a measure of how well a compound donates protons, accepts electrons or lowers the pH in a
  63. Formal charge formula:
    FC= (Column #)-(# of bonds connected to atom) -(# of lone paired electrons)
  64. A bond is polar if...
    the electron density between the two nuclei is uneven
  65. A molecule that DONATES a pair of electrons is considered to be a lewis...
    Lewis base
  66. A molecule that ACCEPTS a pair of electrons is considered to be a lewis...
    Lewis Acid
  67. what are the three types of van der Waals interactions?
    Dipole forces, hydrogen bonding, and london forces
  68. Hydrogen can create hydrogen bonds with which atoms?
    N, O or F
  69. A + B --> AB
    rxn type?
  70. AB -> A + B
    rxn type?
  71. AB -> AX + B
    rxn type?
  72. AX + BY -> AY + BX
    rxn type?
    Double replacement
  73. an oxidizing agent is...
    An agent that oxidizes and is reduced
  74. a reducing agent is...
    an agent that reduces and is oxidized
  75.  a reducing agent, gives up electrons to be...
  76. an oxidizing agent accepts electrons to be...
  77. The higher the kinetic energy of molecules, the ______ it's entropy.
  78. direct conversion from solid to gas is...
  79. direct conversion from gas to solid is..
  80. conversion from liquid to gas
    vaporization (boiling)
  81. conversion from gas to liquid
  82. conversion from liquid to solid is..
    crsytallization (freezing)
  83. conversion from solid to liquid is...
    fusion (melting)
  84. the phase changes that go from a lower energy to a higher energy state are...
    melting, vaporization, sublimation
  85. the phase changes that go from a higher energy to a lower energy state are...
    deposition, condensation and freezing
  86. exothermic phase changes are...
    deposition, freezing and condensation
  87. endothermic phase changes are...
    melting, vaporization, sublimation
  88. heat added or released (heat capacity) equation:
  89. Triple point is...
    the temperature and pressur at  which all the phases exist simultaneously
  90. supercritical fluid is...
    substance in which, liquid and gas phases are no longer distinct
  91. the critical point is...
    the end of the liquid-gas boundary
  92. Temperature is...
    a function of the average translational kinetic energy of the molecule in a system
  93. absolute zero is...
    the lowest possible temperature
  94. how do you convert farenheit to celsius?
    C= (F-32) x (5/9)
  95. how do you convert celsius to farenheit?
    F= (C x 9/5) + 32
  96. how do you convert celsius to kelvin?
    K= C + 273.15
  97. how do you convert Kelvin to celsius?
    C= K-273.15
  98. Pressure formula with force is?
    P=F/a (force per unit area)
  99. P=(N/m2)=?
  100. What is the formula for pascals?
    Pa= (N/m2)
  101. 1 atm = ___ mmHg
  102. 760mmHg = ___ atm
  103. 1 atm= ___torr
  104. 760 torr = _____ Pa
    1.013 x 105 Pa
  105. 1 atm = ___ Pa
    1.013 x 105 Pa
  106. 1 atm = ___ torr = ___mmHg= ____Pa
    • 760
    • 760
    • 1.013 x 105
  107. STP is...
    Standard temperature Pressure
  108. STP is defined as...
    0o Celsius and 760 torr
  109. Kinetic energy of gases formula=
    KE= (1/2)mv2
  110. There is no loss of _______during collisions in gases
    kinetic energy
  111. in the kinetic energy of gases there are no _________ forces between the particles.
  112. the average kinetic energy of the particles is ____________ to the absolute temperature of the particles
    directly proportional
  113. As temperature decreases in a gas the kinetic energy ______.
  114. 1 atm = ___pa (in sci. notation)
    1.01 x 105
  115. Gauge pressure formula...
    (Absolute Pressure - Atmospheric Pressure)
  116. The gauge pressure tells you...
    how much above the absolute pressure is than the atmosphereic pressure
  117. As pressure goes up in a gas, the volume _______
    goes down
  118. The actual volume of gas is equal to...
    the volume of the container plus the excluded volume
  119. excluded volume is...
    The volume occupied by the gas molecules themselves
  120. the actual volume occupied by a gas is always ______ than or equal to the volume calculated by the ideal gas law.
  121. The real pressure is always _____ than the ideal pressure
    less than
  122. The real volume is always _____ than the ideal volume
    less than
  123. What is the boyle's law ?
    under constant temperature and a constnat number of moles of gas, the product of pressure and volume is a constant.
  124. what is boyles law equation?
  125. in boyles law, pressure and volume are ______ proportional
  126. in boyles law, P is proportional to....
  127. in boyles law, V is proportional to....
  128. what is charles' law?
    for ideal gases under constant pressure and a constant number of moles of gas V/T is constant
  129. what is the formula for charles law?
    V1T2 = V2T1
  130. In charles law V is directly proportional to ...
  131. In charles' law, T is directly proportional to...
  132. What is the formula for Gay-Lussac's Law?
    P1T2 = P2T1
  133. in Gay-Lussac's law P is directly proportional to...
  134. in Gay-Lussac's law T is directly proportional to...
  135. The combined gas law equation=
  136. Avagadro's hypothesis equation=
    V1n2 = V2n1
  137. The ideal gas law formula=
  138. R, the universal gas constant is...
    0.0821 L-atm/K-mol
  139. Graham's law of effusion formula =
    (rate of effusion of Gas A/Rate of effuusion of Gas B)=[square root (molar mass of gas B/molar mass of gas A)]
  140. The more stable the carbonium ion, the more easily it is....
  141. the stability of a carbonium ion is greatly increased by ....
    charge dispersal
  142. a teritary carbonium ion is more stable than a secondary or primary carbonium ion because it has...
    three alkyl groups
  143. Which type of reaction is occurring when a metal undergoes corrosion?
  144. How many milliosmols of particles does 1 mole of sodium chloride present?
    2 mOsm (1 mOsm of Na and 1 mOsm of Cl)
  145. What statement best describes how a salt bridge maintains electrical neutrality in the half cells of an electrochemical cell?
    It permits the migration of ions
  146. A salt bridge between half cells prevents...
    the solutions from mixing but allows the ions to move (migrate) from one half cell to the other..
  147. Molarity (M) is the number of
    moles of solute per liter of solution
  148. Heat flow is always from _____ temperature to ____ temperature.
    • high
    • low
  149. STP a mole of gas occupies ______ liters...
  150. When the external pressure is 101.3 kPa torr, water will boil at what temperature?
  151. When the vapor pressure of water is 101.3 kPa, the temperature is .....
  152. When the atmospheric pressure above a liquid equals its vapor pressure, the liquid will...
  153. If the vapor pressure was 50 kPa, water would boil at about...
  154. molarity equation=
    (moles of solute / liter of solution)
  155. what alkaline-earth metal is found in gypsum?
  156. What causes energy to be released in a nuclear reaction?
    fusion and fission
  157. Atomic fusion is the process of...
    combining atoms to form elements of higher atomic weight
  158. atomic fission is the process of...
    splitting an atomic nucleus
  159. Whats the formula for baking soda?

    sodium bicarbonate
  160. When a substance is oxidized, it acts as...
    a reducing agent
  161. A particle accelerator can increase the kinetic energy of...
    an alpha particle and a beta particle
  162. What is the electronic distribution in the orbitals of an oxygen atom?
  163. chlorine and fluorine are _____ at STP.
  164. Iodine is a _____ at STP.
  165. Bromine is a _______ at STP
  166. As the pressure of a gas at 2 atm is changed to 1 atm at constant temperature, the volume of the gas...
  167. what is a property of a reaction that has reached equilibrium?
    The rate of the forward reaction is equal to than the rate of the reverse reaction.
  168. Equilibrium means ......
    equal reaction rates
  169. If HgO is mercuric oxide, what is the symbol of mercurous oxide?
  170. A battery consists of which type of cells
  171. What substance is made up of monomers joined together in long chains?
  172. An electron has the same mass as a ....
    beta particle.
  173. An alpha particle has a mass of...
    4 (2 protons and 2 neutrons)
  174. A proton has the same mass as a...
  175. An atom of which of the following elements has the greatest ability to attract electrons?

    A. Silicon.
    B. Sulfur.
    C. Nitrogen.
    D. Chlorine.
    • chlorine
    • (most electronegative)
  176. At STP, which substance is the best conductor of electricity?
    any metal
  177. The best conductors of electricity are...
  178. Elements that lose electrons form positive ions that are _______ than atoms of the same element.
  179. What statement explains why the speed of some chemical reactions is increased when the surface area of the reactant is increased?
    This change exposes more reactant particles to a possible collision.
  180. What particle cannot be accelerated in a magnetic field?
  181. Only _______ particles can be accelerated in a magnetic field
  182. thermodynamics ________ the rate of reaction
    do not affect
  183. the arrhenius equation is...
    Image Upload 1
  184. The value of k is unique to each reaction at a given....
  185. The value of k will change if _________ is changed
    the temperature
  186. The value of k _________ change with time
    does not
  187. the value of k in not dependent on the concentrations of either _________ or _________.
    reactants or products
  188. the value of k must be determined ____________.
  189. the units of k depend on the overall _________________.
    order of reaction
  190. catalysts operate by altering....
    the activation energy of a reaction
  191. a catalyst can ________ or ______ a reaction
    speed up or slow down
  192. a catalyst that is used to slow down a reaction is called....
    an inhibitory catalyst or an inhibitor
  193. a catalyst is niether consumed nor _________ during the course of a reaction.
  194. a homogenous catalyst is...
    a catalyst that exists in the same phase as the reactants
  195. a hetereogenous catalyst can also be called a...
    contact catalyst
  196. a heterogenous catalyst is..
    a catalyst that exists in a different phase than the reactants
  197. enzymes are...
    proteins that act as homogenous catalysts for specific biochemical reactions
  198. The reaction quotient gives...
    the ratio of products to reactants at equilibrium. (gives the same ratio at all times other than equilibrium)
  199. if Keq >> 1....
    products are favored over reactants
  200. if Keq ≈ 1....
    neither reactants nor products or favored
  201. if Keq << 1.....
    reactants are favored over products
  202. Q>Keq means...
    Products in excess
  203. Q=Keq means....
    at equilibrium
  204. Q<Keq means...
    reactants in excess
  205. Le Chatelier's principle is....
    when a system at equilibrium is subjected to a stress, the equilibirum will shift in a direction that tends to alleviate the effect of that stress
  206. for a gaseous mixture at equilibrium, the overall pressure within a container can be changed either by __________ or by __________.
    • adding more gas to the container or
    • decreasing the volume of the container
  207. in gas, if volume is decreased the pressure is ________. The reaction will be pushed in the direction resulting in ______ moles of gas.
    • increased
    • lower
  208. in gas, if volume is increased the pressure is ________. The reaction will be pushed in the direction resulting in ______ moles of gas.
    • decreased
    • higher
  209. if both sides contain an equal number of gaseous moles, there is no change in equilibirum when ________ is changed
  210. an endothermic reaction requires heat as a _______.
  211. an exothermic reaction requires heat as a ________.
  212. A soultion is...
    a homogenous mixture of two or more chemical compounds
  213. a solvent is..
    a substance into which other chemical are dissolved
  214. a solute is..
    the compound that is dissolved in the solvent
  215. solvation is...
    when a solute is added to a solvent
  216. Hydration is...
    the solvation process when the solvent is water
  217. endothermic solvation = ________ of solution
    positive heat of solution
  218. exdothermic solvation = ________ of solution
    negative heat of solution
  219. the solubility of solids in liquids tends to increase with _______ tempertaure
  220. the solubility of gases in liquids tends to decrease with __________ temperature
  221. the solubility of gases in liquids tends to increase with ________ pressure
  222. a colligative property is...
    a property that depends only on the number of particles present in solution and not on the identity of those particles
  223. Strong electrolytes _____________ completely, or nearly completely
  224. weak electrolytes __________ only slightly
  225. A Hoff Factor is....
    the number of species which a substance dissociates into when solvated
  226. The Hoff factor is signified by the letter ...
  227. CaCl2 .....Hoff factor?
    i=3 (1 Ca + 2 Cl)
  228. osmotic pressure formula...
    ∏ = (Molarity)(hoff factor) (R=.0821)(temperature in K)
  229. Freezing point depression formula=
    ΔTf= -kf im
  230. Boiling-Point elevation formula=
    ΔTb= -kbim
  231. Questions about equimolar solutions are asking for...
    the comparison of Hoff factors
  232. the solute with the largest i will produce the largest...
    colligative change
  233. questions in which equal masses of solute are utilized are often more concerned with the calculation of ....
  234. small, low MW salts will have the most moles in a given mass, hence give a larger ___ and a larger ________ change.
    • m
    • colligative
  235. when equal masses of solute are added to a solution, the _________ one gives the larget colligative change
  236. An open system is...
    a system that allows for the exchange of matter and energy between only the surroundings and the system
  237. a closed system is...
    a system that allowas for the exchange of energy only, the mass in conserved in the system
  238. an isolated system is...
    a system that does not allow for the exchange of anything (matter or energy) between the system and the surroundings
  239. in order for a system to be considered isolated it needs....
    to be a closed system that is in neither mechanical nor themral contact with the surroundings
  240. a state function is determined...
    only by the current state of the system
  241. a nonstate function is ______-dependent.
  242. the common thermodynamic state functions are...(7)
    • pressure
    • temperture
    • volume
    • internal energy
    • enthalpy
    • entropy
    • free energy
  243. enthalpy is...
    a measure of the total energy of a thermodynamic system
  244. entropy is...
    the thermodynamic property toward equilibrium/average/homogenization/dissipation
  245. Work equation in term or pressure and volume=
  246. entroyp increases as temperature _______.
  247. Entropy increases in a reaction if that reaction produces more _______ molecules that is contained ______ molecules.
    • product
    • reactant
  248. Entropy increases when pure liquids and/or pure solids form....
  249. the entropy if the universe always ....
  250. a reaction is _____ when the enthalpy is positive
  251. a reaction is _______ when the enthalpy is negative
  252. the standard thermodynamic conditions are...
    298.15 Kelvin (25oC) at 1 atm
  253. when summing up energies in a reactions always use the basic formula...
    (heat of formation of products) - (heat of formation of reactants)
  254. ΔG = ?
    ΔH - TΔS
  255. When ΔG of a reaction is negative, the reaction is ________ in the ________ driection
    • spontaneous
    • forward
  256. When ΔG of a reaction is positive, the reaction is ________ in the ________ driection
    • nonspontaneous
    • forward directions
  257. When ΔG of a reaction is equal to zero, the reaction is ....
    at equilibrium
  258. a reaction with positive ΔG is called
  259. a reaction with negative ΔG is called
  260. ΔG = ΔG0+ ________.
  261. in an elecrolytic cell, the redox reaction is...
  262. in an elecrolytic cell, the cell requires an ______ flow
  263. in an elecrolytic cell, the anode is the _______ electrode
  264. in an elecrolytic cell, the cathode is the _____ electrode
  265. electrons flow from the ______ to the _______ (cathode, anode)
    anode to cathode
  266. current flows from the _______ to the ______ (cathose, anode)
    cathode to the anode
  267. oxidation occurs at the (anode, cathode)
  268. reduction occurs at eh (anode, cathode)
  269. in galvanic cells, the redox reaction is...
  270. in galvanic cells, the electron flow is ...
  271. in galvanic cells, the positive electrode is the..(anode,cathode)
  272. in galvanic cells, the negative electrode is the..
  273. in electolytic cells, the electron flow is..
  274. concentration cells are..
    galvanic cells, in which the cathodic half and anodic half are in opposite directions
  275. according the the bronsted lowry definiton...

    acids are proton ______
    bases are proton ______
    • donor
    • acceptors
  276. congjugate bases deals with the _______ definition
    bronsted lowry
  277. according to the lewis defintion

    acids are electron-pair _______
    bases are electron-pair _______
    • acceptors
    • donors
  278. according to the arrhenius definition

    acids produce ______ ions
    bases produce ______ ions
    • Hydrogen
    • Hydroxide
  279. large values of Ka and Kb imply...
    strong bases and acids
  280. small values of Ka and Kb imply...
    weak acids and bases
  281. strong acids and bases have ___ pKa and pKb values
  282. weak acids and weak bases have ____ pKa and pKb values
  283. Kw=
  284. pKa + pKb = ?
  285. an acid or base with a large pKa will have a congjugate acid or base with a ____ pKa
  286. kw=[H][OH]= ?
    1 x 10-14
  287. if [H+] = 1 x 10-10 what is the pH?
  288. pH + pOH = ?
  289. pOH = ?
    -log [OH]
  290. OH = ?
  291. pKa = ?
    pKa = ?
    • -logKa
    • -logKb
  292. the more concentrated the buffer....
    the more effective it will be
  293. the pKa of the buffers should be chosen to match...
    the pH that is to be buffered
  294. a buffer is composed of  a weak acid and its______ or a weak base and its ________
    • conjugate base salt
    • conjugate acide salt
  295. the section of a titration curve where the pH changes very gradually is called the....
    buffering domain (or buffering region)
  296. the point at which the pH is neutralize is called the...
    acid-base equivalence point
  297. for a weak acid titrated with a strong base, the equivalence point will occur at...
    pH > 7
  298. for a weak base titrated with a strong acid, the equivalence point will occur at...
    pH < 7
  299. for a strong acid titrated with a strong base, or vice versa, the equivalence point will occur at...
    pH = 7
  300. the pH at half equivalence is equal to...
    the pKa
Card Set
PCAT Gen Chem
PCAT Gen Chem