Answer Key to the Final Review Packet
Naming and Reaction types
1. Potassium peroxide
2. NH4NO3
3.A + B
AB
4. AB + C
CB + A
5. AB A + B
6. AB + CD
AD + CB
7. CxHyOz + O2
CO2 + H2O
8. CO2 + H2O
9. A compound that consists of two elements.
10. PbO2 + Pb + 2H2SO4
B2O3 + 6 HF
11. Attraction between positively and negatively charged ions.
12. A bond between two atoms which is formed by sharing of electrons between the atoms.
13. Dichromate ion
14. Elements in Group VIII and the elements which are most reactive.
15. Element + Oxygen
16. 4NH3 + 7O2
6H2O + 4NO2
17. NH3
18. C2O4
19. Nitrogen oxide.
20. (ClO2)3
21. 2Al(OH)3
Al2O3 + 3 H2O
22. PCl3 + 3H2O
3HCL + H3PO3
23. 9C + 2Al2O3
Al4C3 + 6CO
24. Sodium oxide
25. Magnesium carbonate
26. HSCN
27. (2-)
28. Hydrogen Carbonate
29. H2S + 2NH4Cl
2 HCl + (NH4)2S
30. HClO4
31. chromium (II) sulfate, iron (III) phosphate, ammonium chloride
32. HIO4, NaHCO3, KAsO2
33.NaCN, it is sodium cyanide
34. D, B, A, C
35. NR
36. 2Li + CaO
Li2O + Ca
37. H2 + 2CuI
2HI + 2Cu
38. Na2SO4 + 2NH4C2H3O2
2NaC2H3O2 + (NH4)2SO4 NR
39. 2KOH + H2CO3
K2CO3 + 2H2O
40. MgCl2 + Fr2S
2FrCl + MgS
41. K2O + SO3
K2SO4
42. V2O5 + H2O
V(OH)5
43. Oxygen
44. Na2CO3
Na2O + CO2
45. 2C8H18 + 25O2
16CO2 + 18H2O
46. Yes
47. No
48. Yes
49. K2(Cr2O7) + 14 HCl
3 Cl2 + 7 H2O + 2 CrCl3 + 2 KCl
50. 3 Cu + 8 HNO3
4 H2O + 2 NO + 3 Cu(NO3)2
Stoichiometry
1. The average of the masses of its naturally occurring isotopes weighted according to their abundances.
2. The natural abundance of each isotope of an element is considered to determine the weights.
3. A mole
4. 6.022 x 1023
5. - The molecular weight is the sum of the atomic weights of the atoms in a molecule of a compound.
- The formula weight is the sum of the atomic weights of the atoms in a formula unit.
- The molecular mass is the mass of one mole of any substance.
6. The advantage of using moles is that the quantity
will be much smaller and a number that is easier to deal with than if you use grams or pounds. Also, you can
compare
two quantities of moles to each other, but you cannot
compare grams and pounds.
7. Hydrates are compounds formed by the union of water
with some other substance, generally forming a neutral
body, as certain crystallized salts.
8. The concentration of a solution is usually given in
moles per liter (mol L-1 OR mol/L). This is also known as molarity.
9. In chemistry, the limiting reagent is the chemical
that determines how far the reaction will go before
the chemical in question gets used up, causing the
reaction to stop.
10. It is called the limiting reagent because it
limits the amount of product that can be produced
during a reaction.
What is… (give an example of each)
11. A substance that dissolves in water to form solutions that conduct an electric current. (Ex: Salts, Acids,
bases)
12. A strong electrolyte is a substance that is nearly completely dissociated into ions. (Ex: Sodium chloride,
hydrochloric acid)
13. A weak electrolyte is a substance that dissociates into ions only to a small degree. (Ex: Acetic acid)
14. A nonelectrolyte is a substance whose solution does not conduct an electric current. (Ex: Sucrose)
15. To obtain the molecular formula for a compound, its molecular weight is compared with the weight of the
empirical formula. The simplest formula of the compound can be obtained from the mole ration of the elements,
which are the same as their atomic weight.
16. Avogadro’s number: 6.022 x 1023
17. Avogadro’s number: 6.022 x 1023
18. The isotope used today at the standard for the determination of atomic weight is carbon.
19. 1 mol Cu x 63.55 g of Cu/ 1 mol = 63.55 g Cu
63.55/249.69 = 25%
1 mol S x 32.06 g of S/ 1 mol = 32.06 g S
32.06/249.69 = 13%
9 mol O x 16 g of O/ 1 mol = 144 g of O
144/249.69 = 58%
10 mol H x 1.008 g of H/ 1 mol = 10.08 g of H
10.08/249.69 = 4%
20. NaxClzOy
NaCl
1-.450 = .55g of NaCl .45gO x 1 mol O /16 g O = .02813 mol O
.55 g of NaCl x 1mol/58.44 g NaCl x 1molCl/1molNaCl x 35.45gCl/1 molCl =.3337 g of Cl = .009411 mol Cl
.55g -.337g = .2163 g Na .2163gNa x 1 mol/22.98g Na = .009412 mol Na
NaClO3
21. CxHy
CO2 + H2O
4.055 g CO2 x 1 mol CO2/44.01 g CO2 x 1mol C/1 mol CO2 x 12.01 g C/1 mol C = 1.107 g C = .09223 mol C
.9494 g H2O x 1mol H2O/18 g H2Ox 2 mol H/1 mol H20 x 1.008 g H/ 1 mol H = 1.063 g H = .1055 mol H
1.107/1.214 = 91% .1063/1.214 = 9%
C5H6
22. 5.6 g H2 x 1 ml H2/2.02 g H2 x 1 mo O2/2 mol H2 x 32 g O2/1 mol O2 =44.36 g O2
5.6 g H2 x 1 mol H2/2.02 g H2 x 1 mol of H2O/1 mol of H2 x 18 g of H2O/1 mol H2O = 49.90 g H2O
23. 20gH2SO4 / 98.08gH2SO4 x 1 mol CuSO4(H2O)5 / 2 mol H2SO4 x 249.61 g CuSO4(H2O)5= 25.45 g
CuSO4(H2O)5
25.45 g CuSO4(H2O)5 x .85 = 21.63 CuSO4(H2O)5
Given the following equation: 2 KClO3
2 KCl + 3 O2
24. (18 mol O2)
25. CO2 + CaO
CaCO3
(20.73 g CaCO3)
(Percent yield = 84.6%)
26. 3.52/1.41=2.5 (THE EMPIRICAL FORMULA IS:P2O5)
27. (13.15 grams NH3)
Given the equation 2Al + 6HCl = 2AlCl3 + 3H2
28. (LR= HCl. )
29. (mol AlCl3 =0.0224)
30. 4.00g/mol Helium
Use this equation: 2HCl + Na2CO3
2NaCl + H2CO3
31. 22.1 g NaCl Na2CO3 is LR
For the equation C4H10O7 + 3O2
4CO2 + 5H2O
32. 37.3 g CO2
33. 13.4 g H2O
For the reaction CaO + CO2
CaCO3
34. 27.3 g CaCO3
35. Cl2 is limiting reactant, 76.0 g FeCl3 formed.
36. 0.606 M
37. 42.1%C, 6.48% H, 51.4%O
In 1.28 mol Ag...
38. 138 g Ag
39. 7.71 X 1023 Ag atoms
40. C6H12O6 + 6O2
106 g CO2
6CO2 + 6H2O
Energy
1. This means energy was released during the reaction.
2. The amount of heat required to raise the temperature of on mole of a substance by 1 degree Celsius.
3. The heat capacity of 1 gram of a substance.
4. 3.59 calories
5.Exothermic
6. products= thermodynamically more dynamic
7. Energy is required to break bonds and the same amount of energy is released when that type of bond forms. If
the bond strength is large, the molecule is more stable.
8. One calorie is the heat/energy required to raise 1g H2O 1 degree Celsius.
9. The sum of the internal energy change of a system and its pressure- volume is called delta H enthalpy change.
10. ∆H= ∆E + P ∆V at constant pressure
11. Energy is neither created nor destroyed.
12. Enthalpy changes of different steps of a reaction can be added to obtain the delta H for the reaction.
13. ∆Hrxn = ∆Hf (products)- ∆Hf (reactants)
14. Energy is being released but not absorbed ( an endothermic reaction).
15. C= Q/M∆T
C= 478 J / (199.9 g x 12.02 g) = .199 J/g x degrees Celsius
.199 J/g x degrees Celsius
16. 12.50 L CH4 x 1 mol CH4 x 16.0 g CH4
24.8 L CH4 1 mol CH4 = 6.74 g CH4
6.74 g CH4
17.
1 S + 1 O2
1SO2
∆H = -297Kj/mol
1 SO2 + 1/2 O2
1SO3
∆H = -144Kj/mol
1 SO3 + 1 H2O
1 H2SO4 ∆H = -84Kj/mol
-297 + -144 + -84 = -525
∆H = -525 kJ/mol S (*remember: use whatever product/reactant there is one whole mole of (i.e. 1S as opposed
to 1/2 O2 when giving the unit of mol/x.)
18. Reaction:
3 C +1 SiO2
1 SiC + 2CO
0 + -205
-27 + -52 = +126 KJ/mol SiO2
+126 KJ/mol SiO2 ; Endothermic reaction
19. 1550 kJ x 1 mol C2 H4 x 28.4 C2 H4
1412 KJ
1 mol C2 H4 = 30.7 g C2H4
30.7 g C2H4
20. 2.1 x 105 joules
21. 11.1 degrees Celsius
22. C= Q/M∆T
C= 478 J / (199.9 g x 12.02 g) = .199 J/g x degrees Celsius
Final Answer: .199 J/g x degrees Celsius
23. 12.50 L CH4 x 1 mol CH4 x 16.0 g CH4
24.8 L CH4 1 mol CH4 = 6.74 g CH4
Final Answer: 6.74 g CH4
24. 1 S + 1 O2
1 SO2 + 1/2 O2
1 SO3 + 1 H2O
1SO2
∆H = -297Kj/mol
1SO3
∆H = -144Kj/mol
1 H2SO4 ∆H = -84Kj/mol
-297 + -144 + -84 = -525
Final Answer: ∆H = -525 kJ/mol S (*remember: use whatever product/reactant there is one whole mole of (i.e.
1S as opposed to 1/2 O2 when giving the unit of mol/x.)
25. 3C +1SiO2
1SiC + 2CO
0 + -205
-27 + -52 = +126 KJ/mol SiO2
Final Answer:
+126 KJ/mol SiO2 ; Endothermic reaction
26. C2 H4 + 3 CO2
2 CO2 + 2 H2O
+52 + 0
-788 + -527
-1412 = ∆H
1550 kJ x 1 mol C2 H4 x 28.4 C2 H4
1412 KJ
1 mol C2 H4 = 30.7 g C2H4
Final Answer: 30.7 g C2H4
Periodicity
1.speed of light divided by wavelength
2. hv
3. UV
4. 400-700nm
5. quantum levels
6. s, p, d, f
7. K, L, M, N
8. 6
9. +1/2, -1/2
10. 14
11. Metals, non-metals, metalloids
12. Families (alkali metals, alkaline earth metals, halogens, noble gasses)
13. Representative elements, transition metals, inner transition metals
14. s-elements, p-elements, d-elements
15. It decreases going down because added energy levels shield the power of the nuclear charge making it easier
to remove most electrons. It increases going to the right because the increase in nuclear energy makes it more
difficult to remove the outermost electrons.
16. 1st ionization energy is the energy needed to remove one electron. 2nd ionization energy is the energy
needed to remove a second electron.
17. Ra, Pd, Se, F Ne.
18. 2nd ionization energy
19. Smaller up and right. Larger down and left.
20. F, Cl, P, Ge, Ni, Pd, Y, Ba, Ra.
21. La, W, Mn, Ni, B, C, He.
22. Co
23. F
24. positive ions are always smaller than the parent atoms and negative ions are always larger.
25. period number
26. high
27. Selenium
28. [Ar] 4s1 3d10
To complete its D shell it steals an electron from the S orbital
29. Noble gases
30.C) group 2, 6, 7 or 8
31. Francium (7. 0. 0. +1/2.)
32. a. 10
33. b. 3
34. b. 2
35. c. 3
36. d. circle
37. Ca
38. size: F, N, Rb, Cs
electron affinity: Cs, Rb, N, F
39. Br, because acids turn blue litmus red, and nonmetals like Br tend to produce acids.
40. Mg, Zn
41. O2- will have a greater atomic radius, because the two extra electrons in O2- occupy outermost shells and
increase electron repulsion, expanding the radius.
42. n=4, l=2, m=+1, s=-1/2 (or +1/2)
43. Fr
Gas Laws
1. What is the density of a gas that is 1.996g with a volume of 1190cm3? b
2. 3.200 g of a gas is 5.080 moles. What is its molar mass? c
3. Oxygen gas effuses through a capillary in 2.00 seconds. An unknown gas of the same volume effuses in
4.00 seconds. What is the molar mass of the unknown gas? a
4. In a closed end manometer, the mercury level was 540.mm higher on the closed end than on the gas end.
What was the gas pressure? d
5. If the Thirsty Bird (think Gay Lussac’s gas law) dips his head in water and cools down from 50◦C to 30◦C,
and the pressure in his belly was originally 1 atm, what was the pressure after his drink? b
6. A snake balloon has .00100 moles of air in it and a volume of .100 mL. If I blow .028 moles of air into it,
what is its volume? b
7. T1=207K. T2=301K. n1=.400 moles. n2=.275 mol. Which law is this? a
8. An He molecule, weighing 4.0 g/mol at 200K has ____times as much K.E. as an H2 molecule, weighing 2.0
g/mol, at 200K? a
9. H2 molecules (2.00 g/mol) at 200.K go ____as fast as He molecules (4.00 g/mol) at 600.K? d
10. Charles’ law: a gas with a volume of 700.mL at 300.K has what volume at 383K? d
a. 834 L
b. 789 L
c. 0.789 L
d. 0.834 L
11. In an open end manometer with an atmospheric pressure of 37.8 kPa, the Hg level was 27.3 mm higher on
the left. What is the gas pressure? c
12. At 27 degrees Celsius, a gas, was at 321 kPa, at what temperature would it be at 1.00 atm? a
13. 7.36 grams of a gas occupies 2.67 liters at 17 degrees Celsius and 115.2 kPa. How many moles of gas is it?
d
14. What is the density of MgO at 731 K in 7.32 psi? b
15. What is the molecular weight of a gas that has a mass of 13.2 grams, a volume of 3.7 liters, at 32 degrees
Celsius, and 117 kPa? b
16. 113.cm3 of gas measured at 183.kPa, 343.K, would occupy what volume at SATP? V2 = 174.cm3
17. What is the Volume of 0.936 moles of gas at 347K, 117 kPa? V=22.4 L
18. What volume of oxygen gas, measured at 35OC and 115kPa is required to completely burn 50.0g of Mg?
22.9 L O2
19. What is the volume of 14.7 g of F2 gas at -15.8OC, 187 kPa? V= 3.90L
20. At what temperature will 1.43 moles of gas produce a pressure of 132. kPa in a 440.cm3 flask? T=4.89K
21. 3.00
22. 0.462
23. 8.22 g/mol
24. 0.751 g/L
25. 29 L
26. 644 K
27. 1.70 mol
28. 504 kPa
29.1480K
30. 673 mmHg
31. 673 mmHg
32. 770. mmHg
Convert to Kelvin:
33. 248K
34. 420 K
35. 241.2K
36. 296 K
37. 254 K
38. 0.542 atm
39. 5720 mmHg
40. 1420 kPa
41. 721 torr
42. 0.164 mol
43. 0.645 g/L
44. 0.267 g/L
45. 298 mmHg