FINAL CHEM

q=heat
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q=heat
What does q denote?
ΔE=q+w; where q=heat and w=work
What is the formula for the change in energy?
The system gains heat; work is done on the system by the surroundings
What does +q value indicate?
The system loses heat; work is done by the system on the surroundings
What does -q value indicate?
work is done on the system by the surroundings
What does a +w value indicate?
work is done by the system on the surroundings
What does a -w value indicate?
Net gain of energy by the system
What does a +ΔE indicate?
Net loss of energy by the system
What does a -ΔE indicate?
positive
If ΔV is negative, what will the value of work be?
negative
if ΔV is positive, what will the value of work be?
ΔH; the heat flow between reactants and productsWhat is enthalpy of a reaction?By the change in temperatureHow is enthalpy measured?1. The energy required to break a bond 2. The same value as it's bond enthalpy, but negative1. What is bond enthalpy? 2. What is the amount of energy required to make a bond?Absorbed; value for ΔH is positive; reaction is endothermicWhen bonds are broken, energy is...Released; value of ΔH is negative; reaction is exothermicWhen bonds are made, energy is...chemical reaction that forms one mole of a substance from it's elements in their standard statesWhat are formation reactions?the amount of heat (energy) required to change 1 g of a substance by 1 degree celsiusWhat is the specific heat capacity?It will take more heat to change the temperature of the substance compared to others; the substance will absorb/release more heat when changing temperaturesWhat does a large heat capacity of a substance mean?Monoatomic solids Mercury (Hg), which is liquidWhat is the standard state of all metals? What is the one exception?Br2 (l), I2 (s), all others are (g)What are the standard states of the diatomic elements?(s, graphite)What is the standard state of carbon?1. If you reverse a reaction (switch reactants and products) you must change the sign for the value of ΔH 2. If you double or divide a reaction you must double or divide the value of ΔHWhat are the two rules pertaining to manipulating reactions for Hess's law?1. Pressure and volume are inversely related 2. pressure and temperature are directly proportional 3. volume and temperature are directly proportional 4. volume and # of moles are directly proportionalWhat are the four relationships between P, V, n, and T designated by the gas laws?Molar mass; heavier gases are more dense, lighter gases are less denseDensity of a gas is directly related to it's...molar mass of the gas (in g/mol) NOT #of molesIn the equation for density of a gas, what does M denote?1. X1 2. (moles of X)/(total moles of rxn)1. What is the notation for the mole fraction? 2. How do you calculate the mole fraction?1. High temperature 2. Low pressureUnder what conditions is a gas expected to behave most like an ideal gas?As molar mass increases, velocity decreases; lighter molecules move fasterHow is molar mass related to molecular velocity of a gas?qcal=Ccal x ΔT Ccal=calorimeter constantHow do you calculate qcal?qrxn + qcal=0what is the formula for calorimeter calculations involving a bomb calorimeter?qrxn + qcal + qcontents =0what is the formula for calorimeter calculations involving a coffee-cup calorimeter?same equation as regular q calculations!! qcontents=m x Ccontents x ΔT Ccontents is most likely the specific heat of waterhow do you calculate qcontents?Use the least number of DECIMAL PLACESWhat is the rule for significant digits when adding or subtracting?Use the least number of total SIGNIFICANT FIGURESWhat is the rule for significant digits when multiplying or dividing?Physical Change: The substance remains the same, usually the state changes (s, l, g, etc.) Chemical Change: The substance changes, breaking/forming of chemical bonds usually the result of a chemical reactionExplain a Physical Change vs. Chemical ChangeGiga=1,000,000,000; 10^9 Mega=1,000,000; 10^6 Kilo=1,000; 10^3 Hecto= 100; 10^2 Deka=10; 10^1 Deci=0.1; 10^-1 Centi=0.01; 10^-2 Mili=0.001; 10^-3 Micro=0.00000; 10^-6 Nano=0.0000000010; 10^-9 Pico=0.0000000000010; 10^-12What are the SI prefixes and their values?The number of protons of that element; provided on the periodic tableWhat is the atomic number of an element? Where can it be found?The total number of subatomic particles in the nucleus of an element (protons + neutrons); must either be calculated or provided, NOT the mass provided on the periodic tableWhat is the mass number of an element? Where can it be found?P= 1+ N= no charge E=1-How are the subatomic particles (protons, neutrons, and electrons) charged?Atoms of an element that have different numbers of neutrons in the nucleus; therefore have a different mass numberWhat is an isotope?1. Top left=mass number 2. Bottom left=atomic number 3. Middle=element symbol 4. Top right= charge (if applicable)What are the (4) components of a shorthand element diagram?Wavelength and frequency are inversely related; as wavelength increases, frequency decreases; as wavelength decreases, frequency increasesWhat is the mathematical relationship between wavelength and frequency?Wavelength and energy are inversely related; as wavelength increases, energy decreases; as wavelength decreases, energy increasesWhat is the mathematical relationship between wavelength and energy?Frequency and energy are directly proportional; as energy increases, so does frequency; as energy decreases, so does frequencyWhat is the mathematical relationship between frequency and energy?Gamma rays, X rays, Ultraviolet, Visible light, Infrared, Microwaves, Radio wavesWhat is the order of the electromagnetic spectrum from high to low energy?Purple, blue, green, yellow, orange, redWhat is the order of visible light from high to low energy?c=speed of light; provided constantWhat does "c" denote in regards to frequency calculations?h=planck's constant; provided constantWhat does "h" denote in regards to frequency calculations?v=frequencyWhat does "v" denote in regards to frequency calculations?λ= wavelengthWhat does "λ" denote in regards to frequency calculations?Meters (M)What is the SI unit for wavelength?Hertz (Hz)What is the SI unit for frequency?The electron is in its lowest energy state; at a low energy levelWhat does it mean if an electron is in a ground state?The electron has absorbed energy; moved to a higher energy leverWhat does it mean if an electron is in an excited state?Region where an electron is likely to be foundWhat is an orbital?The horizontal rows of the periodic tableWhat is a period on the periodic table?The vertical columns of the periodic table?What is a group on the periodic table?n= the energy level of an electron; corresponds to the period of an element ex. Na is in period 3; n=3What is "n" in regards to quantum numbers?l=the shape of orbital/shape of the sub shells; values are l=(n-1); ex. if n=3; l=2 and the electron is in d-orbitalWhat is "l" in regards to quantum numbers?l=(n-1) l=0; s-orbital l=1; p-orbital l=2; d-orbital l=3; f-orbitalWhat are the possible values of "l" and the corresponding orbitals?m l=the number of orbitals per energy level; values range from -l to +l ex. l=1; then m l=-1, 0, 1; this explains why there are three p orbitalsWhat is "m l" (m sub l) in regards to quantum numbers?m s=the spin of the electrons; values are EITHER -1/2 or +1/2What is "m s" (m sub s) in regards to quantum numbers?From the orbital with the highest principle quantum number (value of "n"; corresponds to rows on the periodic table)When filling in an electron diagram for an ion (namely a cation), from where do you remove the electrons first?Down and to the left; Fr is the element with the smallest atomic radiiHow does atomic radii increase when looking at the periodic table?Cation has lost electrons; smaller radii Anion has gained electrons; larger radiiCompare the atomic radii of a cation and an anionUp and to the rightHow does ionization energy increase when looking at the periodic table?The amount of energy needed to REMOVE 1 mole of electrons; likelihood of giving up an electron to form a cationWhat is ionization energy?Up and to the rightHow does electron affinity increase when looking at the periodic table?The amount of energy needed to ADD 1 mole of electrons; likelihood of gaining an electron to form an anionWhat is electron affinity?Up and to the rightHow does electronegativity increase when looking at the periodic table?In a covalent bond, the tendency of one atom to pull electrons towards itself; unequal sharing of electronsWhat is electronegativity?Diagonally down and to the leftHow does metallic character increase when looking at the periodic table?Diagonally up and to the rightHow does nonmetallic character increase when looking at the periodic table?The effective nuclear charge; the net positive charge attracting valence electrons toward the nucleus of an atomWhat does Z-eff denote?That nuclear charge (net positive) felt by the valence electrons of an atom; positively charge protons in the nucleus pull the electrons closer, while shielding electrons repel valence electrons awayWhat is the effective nuclear charge?Effective nuclear charge; Zeff=the number of valence electrons of an atom; group number on the periodic tableWhat is the shortcut for finding the value of Zeff?Ionic bondA bond between a cation and an anion; typically a metal and a nonmetalMetallic bondA bond formed between two metalsCovalent BondA bond formed between two nonmetals; either polar or non polarElectrons are shared unequally between the two atoms in the bondWhat does it mean if a covalent bond is polar?Electrons are shared equally between the two atoms in the bondWhat does it mean if a covalent bond is non polar?1. Charge of ion; the more charged (either positive or negative) the higher the lattice energy; charge if more influential 2. Size of ion; the larger the ions in the compound the more lattice energyWhat two factors influence the magnitude of lattice energy (coulomb attraction) in ionic bonds?Which is more influential?1. DRAW THE LEWIS DOT STRUCTURE 2. formal charge= Valence electrons (group number of atom) - [sticks+dots]How do you calculate the formal charge of an atom in a molecule?To determine if the most correct structure is drawn; the structure with the least formal charge is most correct In a neutral molecule, net formal charge should equal 0 For an ion, net formal charge should equal the charge of the ion (positive or negative)What is the purpose of formal charge? What should the formal charges of all atoms in a neutral molecule equal? What should the formal charges of all atoms in an ion equal?Lewis structures for the same element with the same arrangement of atoms but different arrangement of bonds/bonding electrons; atoms DO NOT move, bonds and lone pairs are rearrangedWhat is a resonance structure?Resonance structures for a molecule that ONLY involve the movement of double or triple bonds between identical atom structures; ONLY double and triple bonds are rearrangedWhat are equivalent resonance structures?H(2), B (6), Al(6), and Be (4)What four elements can have less than a full octet when drawing a Lewis Dot Structure?Period 3 elementsWhat elements can have expanded (more than 8) octets when drawing a Lewis Dot Structure?In general, asymmetrical arrangement of atoms means the molecule is polarHow can you tell if a molecule is polar based off the Lewis Dot Structure?Method of electron counting to determine bond angles? A= central atom X= # of atoms bonded to the central atom E= # of lone pairs on central atomWhat is AXE notation? What does "A", "X" and "E" denote?1. convert % to mass in g; values will be the same 2. convert g to moles 3. divide by the smallest number of moles to determine the subscripts for the empirical formulaHow do you create an empirical formula from percent by mass?1. Divide the molar mass of the molecular formula by the molar mass of the empirical formula; value should be an even number 2. Multiply all the subscripts in the empirical formula by the value from previous step; that is the molecular formulaHow do you convert an empirical formula to a molecular formula?1. Write out the total ionic equation; split up (aq) ionic compounds and (aq) STRONG acids into their separate ions 2. Cancel out any ions that are the same in reactants and products; that is your net ionic equation.How do you write a net ionic equation?1. HCl 2. HBr 3. HI 4. HNO3 5. H2SO4 6. HClO4 7. HClO3What are the seven strong acids?Phosphorus, P4What single element is tetratomic in nature?Sulfur, S8What single element in octatomic in nature?Strong bases are usually hydroxides; OH- bonded to something For writing net ionic equations; (aq) strong acids/bases and (aq) ionic compounds are split into their individual atomsHow to identify strong bases? Why do you need to know strong acids/bases?Acid/Base react to neutralize each other (no excess H+ or OH-) Produces water + saltsWhat is a neutralization reaction? What are the expected products?Two substances combine to form a single substance; A+B--->ABWhat is a synthesis reaction?One substance breaks down into two or more substances; AB---> A+BWhat is a decomposition reaction?1. A rapid reaction that produces heat/flame 2. A hydrocarbon (C + H) and oxygen gas 3. Carbon dioxide (CO2) and water (H2O)What is a combustion reaction? What are the reactants? What are the expected products?Oxidation is loss; Reduction is gain; The species that is oxidized losses electrons (becomes more positive) and the species that is reduced gains electrons (becomes more negative)Explain the significance of OIL RIGSpecies that is oxidized; causes other species to be reducesIn a redox reaction (oxidation/reduction) what is the reducing agent?Species that is reduces; causes other species to be oxidizedIn a redox reaction (oxidation/reduction) what is the oxidizing agent?1. Elements always = 0 2. Ions are always = to their assigned ionic charge 3. F always = -1 4. O=-2 (unless with peroxide H2O2 where it is -1) 5. H=+1 (unless with a metal where it is -1) 6. The sum of all oxidation numbers must equal the overall charge of the compound.What are the six rules to remember for Oxidation numbers(For a redox reaction) A charge assigned to every atom in a compound based on the distribution of electronsWhat is an oxidation number?1. All group 1 metals 2. Group 2 sulfides (any element from group 2 + sulfur) 3. NH4+; ammonium 4. NO3-; nitrate 5. C2H3O2-; acetate 6. ClO4-; perchlorateWhat 6 substances are ALWAYS soluble?1. Compounds containing Cl-, Br- and I- are soluble EXCEPT when paired with Ag+, Hg2 2+, and Pb2+ 2. Compounds contains F- are soluble EXCEPT when paired with Pb2+, and any group 2 metals 3. Compounds containing SO42- are soluble EXCEPT when paired with Ca2+, Sr2+, Ba2+, Ag+ and Pb2+What are the 3 conditional solubility rules?Pb2+; Lead (II) ionIf a soluble substance is paired with _____ it is ALWAYS insoluble1. NH4+; ammonium 2. H3O+; hydroniumWhat are the two positively charged polyatomic ion?1. HPO4 2-; hydrogen phosphate 2.SO4 2- sulfate 3. SO3 2-sulfite 4. CO3 2-carbonateWhat are the 4 double charged anions?PO4 3-; phosphateWhat is the only triply charged anion?1. For metals in Group 1 and 2, and Al, Ag, Cd, and Zn: name of the metal + name of the nonmetal ending in -ide 2. For ALL OTHER metals: name of metal (w/ roman numeral to designate charge) + name of the nonmetal ending in -ide 3. Some metals can exist in multiple forms (ex. Fe+, Fe2+, Fe3+) so you must designate which form is in the compoundWhat are the (2) rules for the naming of ionic compounds? Why are some metals name differently?1. Use greek prefixes; Greek prefix+name of the first element + Greek prefix+name of the second element ending in -ide 2. If the first element is monoatomic, omit the mono- prefix; a name should NEVER begin with mono-What are the (2) rules for the naming of covalent compounds?1. That acid name ends in -ous when the anion ends in -ite; when the anion is a polyatomic ion 2. The acid name ends in -ic when the anion ends in -ate; when the anion is a polyatomic ion 3. The hydro-prefix is used when the anion ends in -ide; when the anion is an elementWhat are the (3) rules for the naming of acids?LinearWhat is the electron geometry of a substance with 2 electron groups?Trigonal planarWhat is the electron geometry of a substance with 3 electron groups?TetrahedralWhat is the electron geometry of a substance with 4 electron groups?Trigonal bipyramidalWhat is the electron geometry of a substance with 5 electron groups?OctahedralWhat is the electron geometry of a substance with 6 electron groups?LinearWhat is the molecular geometry of a substance with 2 electron groups and 0 lone pairs?Trigonal planarWhat is the molecular geometry of a substance with 3 electron groups and 0 lone pairs?BentWhat is the molecular geometry of a substance with 3 electron groups and 1 lone pairs?TetrahedralWhat is the molecular geometry of a substance with 4 electron groups and 0 lone pairs?Trigonal pyramidalWhat is the molecular geometry of a substance with 4 electron groups and 1 lone pairs?BentWhat is the molecular geometry of a substance with 4 electron groups and 2 lone pairs?Trigonal bipyramidalWhat is the molecular geometry of a substance with 5 electron groups and 0 lone pairs?SeesawWhat is the molecular geometry of a substance with 5 electron groups and 1 lone pairs?T shapedWhat is the molecular geometry of a substance with 5 electron groups and 2 lone pairs?LinearWhat is the molecular geometry of a substance with 5 electron groups and 3 lone pairs?OctahedralWhat is the molecular geometry of a substance with 6 electron groups and 0 lone pairs?Square pyramidalWhat is the molecular geometry of a substance with 6 electron groups and 1 lone pairs?Square planarWhat is the molecular geometry of a substance with 6 electron groups and 2 lone pairs?180What are the bond angles of a (linear, linear) molecule?120What are the bond angles of a (trigonal planar, trigonal planar) molecule?<120What are the bond angles of a (trigonal planar, bent) molecule?109.5What are the bond angles of a (tetrahedral, tetrahedral) molecule?<109.5What are the bond angles of a (tetrahedral, trigonal pyramidal) molecule?<109.5What are the bond angles of a (tetrahedral, bent) molecule?120 and 90What are the bond angles of a (trigonal bipyramidal, trigonal bipyramidal) molecule?<120 and <90What are the bond angles of a (trigonal bipyramidal, seesaw) molecule?<90What are the bond angles of a (trigonal bipyramidal, t shapedl) molecule?180What are the bond angles of a (trigonal bipyramidal, linear) molecule?90What are the bond angles of a (octahedral, octahedral) molecule?<90What are the bond angles of a (octahedral, square pyramidal) molecule?90What are the bond angles of a (octahedral, square planar) molecule?spWhat is the hybridization of a molecule with 2 electron domains?sp2What is the hybridization of a molecule with 3 electron domains?sp3What is the hybridization of a molecule with 4 electron domains?sp3dWhat is the hybridization of a molecule with 5 electron domains?sp3d2What is the hybridization of a molecule with 6 electron domains?mono-, di-, tri-, tetra-, penta-, hexa-, hepta-, octa-, nona-, deca-Greek prefixes 1-10(when comparing between two resonance structures) The more electronegative atom will prefer to carry the negative formal chargeHow are electronegativity and formal charge related?A=central atom X= the number of bonds on the central atom (single/double/triple bonds all count as 1) E= the number of lone pairs on the central atomWhat is AXE notation?1.do no conduct electricity (EXCEPT for acids; which are electrolytes in solutions only) 2. can be solid, liquid, or gaseous at room temp 3. low melting and boiling pointWhat are the 3 properties of covalent compounds? (conductivity, state, and melting/boiling point)1. conduct electricity (form electrolytes) in solutions and when melted 2. solid at room temp 3. high melting and boiling pointWhat are the 3 properties of ionic compounds? (conductivity, state, and melting/boiling point)