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Gas/Water/Law
Periodic Table
Formulas/Solutions
Intermolecular Interactions/Law
Acids/Bases & Titrations/Redox
100
What do the graphs for 1) volume & temperature 2) pressure and volume 3) moles and volume look like?
1) at a constant pressure it's a positive linear relationship 2) P1V1 = P2V2 inverse relationship 3) at constant pressure it's a positive linear relationship
100
What are the shapes of the different orbitals and among 3s 3p which is the largest spherical probability?
S = spherical, p = dumbbell/hourglass, d = 4 leaf clovers, f = weird, biggest is 3s and it's spherical
100
How many different structural formulas are available for SO3 and why are there different structural formulas? Is it stable?
3 because there are three resonance structures. It is stable
100
What kind of hybridized orbitals exist between carbon atoms in 1) acetylene 2) ethene 3) ethane
1) C- triple bond-C triple bond so it's sp orbital 2) C-double bond-C so it's sp2 3) C-single bond-C so it's sp3
100
When solving a titration problem what do you need to do first?
You need a BALANCED EQUATION.
200
What is the fraction used to correct a given volume of gas at 235 K to its new volume when it is heated to 450 K and the pressure is kept constant?
450/235 because V1/T1 = V2/T2 so V2 = V1*(T2/T1) so the correct is T2/T1 or 450/235
200
Out of the alkali metals which is the most reactive and why?
Fr is most reactive because it's bottom left (low electronegativity) and very large radius so electron is far away from nucleus
200
Acid has Ka = 1 x 10^-4 and its formula is HA -> H+ and A-. What is the pH? (assume HA = 1 M)
ka = [products]/[reactants] = [H+][A-]/[HA] Ka = 1x10^-4 = x^2/1 so you square root to get H+. H+ = 1x10^-3 so pH = -log H+ or 3
200
Order the following in terms of bond strength? - coordinate covalent bonds, ionic bonds, hydrogen bonds, van der waals, covalent network, dipole dipole forces
1. weakest = van der waals (only momentarily existing between usually non polar molecules 2. dipole dipole bonds 3. hydrogen bonding 4. ionic bonding & covalent (depends) 5. network covalent (diamonds)
200
You have 2.0 M H3PO4 and .5 L of 1M of NaOH. How much H3PO4 do you need in mL?
.5 moles of OH- so you need .5 moles of H+. Remember you have 2.0 moles of H3PO4!!! and each mole has 3 H+s!!
300
For the haber process NH3 + heat <--> N2 + 3H2 I. The reaction to the right will increase when pressure is decreased. II. The reaction to the right will decrease when the temperature is decreased. III. The reaction to the right will decrease when NH3 is removed from the chamber.
I. When pressure is decreased it favors more moles so it favors the right reaction II. When temp is decreased you want to make more heat so it moves to the left. III. It will decrease because when NH3 is removed you want to make more of it so the left reaction increases thereby decreasing the right reaction.
300
What is the oxidation number of an element in group 17? What is the oxidation of an element in group 18? What is the oxidation number of an element in group 2?
Group 17 = -1 (reduced) Group 18 = 0 Group 2 = +2 (oxidized)
300
What happens to the equilibrium constant Keq as 1) reactant concentration change 2) product concentration change 3) temperature change 4) pressure of individual gases for gas reactions Also what is the Keq equation for H2o2 -> H2O + O2
1) stays the same 2) stays the same 3) temperature changes. If temp goes up it favors the more endothermic side. If temp goes down it favors the exothermic side. 4) don't change 2H2o2 -> 2H2o + o2 --> keq is [h2o]^2[o2]/[h2o2]^2
300
Hrxn for decomposition of 2 mole of sodium chlorate? Hf = -85.7 kcal/mol for NaClO3, NaCl (s) = -98.2 kcal/mol,
O2 is a element gas so its Hf = 0. 1 mole decomposition Hrxn is -12.5 kcal. For two moles it's -25 kcal.
300
What mass of aluminum will be completely oxidized by 2 moles of oxygen at STP?
Remember to balance first and check oxidation states! Al becomes Al3+! So Al + O2 -> Al2O3 (needs balancing). You have 2 moles of O2, so...? (72 g - check your answer)
400
What is the molar mass of water?
18 g /mol
400
How do you elevate boiling point and decreasing freezing point?
Increasing solutes in solution. Equation for changes in temperature of these different points = delta k m i (constant * molality * molecules/molecule for example i is 2 for NaCl.
400
Zn + SnCl2 -> Sn + ZnCl2 Sn + CuCl2 -> SnCl2 + Cl Which is the most active metal for the following: a. Sn b. Cu c. Zn. d. Cl e. ZnCl2
Definitely not d or e. Zn replaces Sn, which replaces Cu hence in the activity series Zn is the most active.
500
What is Hess' Law?
heat of formation of products - reactants is the heat of the reaction.
500
Which of the substances listed elevates the boiling point more than the others for 500 g of benzene and why? 1) C6H4Cl2 2) NaCl 3) AlCl3 4) C2H5OH 5) C12H22O11
1) 0.3 moles 2) 5/76 which is <.3 moles 3) <.3 4) <.3 5) <.3 So you want most moles!!! KCl 1 mole dissolves into 2 moles of ions.
500
When SO2 is bubbled through water what is formed? How do you form sulfuric acid?
SO2 + H2O -> H2SO3 or sulfurous acid H2O + SO3 -> H2SO4 another way HSO4- + H2O -> H2SO4
500
A saturated solution of PbS at 25 degrees C contains 5.0 x 10^-14 moles/L of Pb2+ ions. What is the Ksp? What if the solution was PbF2?
It's 2.5 x 10^-27 because Ksp = [ion1]^molar concentration x [ion2]^molar concentration Ksp = [x][x], = (5.0 x 10 ^-14 )^2 For PbF2 Ksp = [x][2x]^2 so it's (5.0x10^-14)(2(5.0x10^-14))^2
500
In the reaction of Zinc with HCl to form H2 what will increase the reaction rate?
1. increasing temperature 2. increase surface area 3. higher concentration 4. forming precipitate.