Bond strengths in kcal/mole
C=O is 191.0, O=O is 118, H-O is 109.7,
H-C is 98.2, C-C is 82.7
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Rh=2.18x10-18J
c = 3.00x108 h = 6.626x10-34Js
me = 9.11x10-31kg
DE=RhZ2(1/n12-1/n22) E = hn c = ln Ephoton=Eb+ Ek Ek=1/2mv2
l = h/mv Ek=¤mv2
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1. An Iron skillet weighing 1.51 kg is heated on a stove to 178°C. Is there enough energy stored in the skillet to cook a 50.0 g egg without adding an additional heat? Note: The egg's temperature must be raised to 100°C to denature the proteins (cook it). Assume that the segg =4.25 J/g°C.
2. 50.0 g of copper at 100.0°C is placed into 50.0g of water in a coffee cup calorimeter at 20.0°C. What is the resulting temperature of the system. Assume Ccalorimeter=0.
3. A Tootsie Roll Pop has a mass of 17.0 g and can be assumed to be pure sucrose (C12H22O11). a) How many dietetic Calories are in one Tootsie Roll Pop? Hint: Heat of combustion. b) How many times would a 50.0 kg boy need to jump 10 cm off the ground to burn off this much energy? Hint E=nmgh where n is the number of jumps and mks units must be used.
4. A calorimeter having a heat capacity of 35.0 cal/°C contains 150.0 ml of 1.00 M hydrochloric acid at 20.0°C and 50.0 ml of 1.00 M Ba(OH)2 at 20.0°C is added. The temperature of the system increases to 22.2°C. What is the DH for the formation of 1 mole of water?
5. .600 g of benzoic acid is combusted (burned) in a bomb calorimeter to determine the heat capacity of the calorimeter, and the temperature increases by 3.05°C. The heat of combustion, DH, for benzoic acid is 771.2 kcal/mole. Next, .300 g of an unknown is combusted in the same calorimeter, and the temperature increases by 1.35°C. What is the DH of combustion for this unknown?
6. A sample of natural gas is 80.0% CH4 and 20.0% C2H6 by mass. What is the heat given off when 1.00 g of this mixture is burned?
7. Find DH°f for the formation of one mole of tungsten carbide, WC(s), from tungsten and carbon given the following thermochemical data.
2W(s) + 3O2(g) ---> 2WO3(s); DH
= -1890.6 kJ
C(s) + O2(g) ---> CO2; DH
= -393.5 kJ
2WC(s) + 5O2 ---> 2WO3(s) + 2CO2;
DH = -2391.6 kJ
8 Describe Dalton’s view of the atom?
9 Describe J.J. Thompson’s contribution to the description of the atom.
10 Describe Robert Millikan’s contribution to the description of the atom.
11 What three types of radiation were descovered by Ernest Rutherford.
12 Describe Rutherford’s contribution to the description of the atom.
13 What is the speed of light?
14 What three things can be found given the wavelength of light.
15 Describe the development of the Bohr atom.
16 What did Max Plank discover.
17 What did A. Einstein receive the nobel prize for?
18 If light of 351 nm is required to remove an electron from the bulk of metalic cesium to the surface of the metal, what velocity will the emitted elelctrons have if light of 350 nm is shown on the surface of cesium metal?
19 What is the average radius of the n=3 level in hydrogen?
20 What is the average energy of the n=3 level in hydrogen?
21 What frequency and wavelength is emitted form and electron that drops from the n=5 to n=2 energy level in hydrogen?
22 What is the (De Broglie) wavelength of an electron traveling at .1c?
23 What is the contribution of E. Schrodinger to quantum theory?
24 Give all quantum number for the electorns in sulfur.
25 Give all quantum numbers for the electrons in the outer shell of argon.
26 What frequency of light will be emitted if an electron drops from the n= 3 level to the n=2 level in Li2+ ?
27 Give the electron configuration of Br-1, and Ni2+, and W.
28 Give the orbital diagram for the elements Br-1, and Ni2+, and W.
29 In what directions on the periodic table does atomic size increase?
30 In what directions on the periodic table does Ionization energy increase?
31 In what directions on the periodic table does Electron affinity increase, and what two periods does this trend vary significantly?
32 Put the following in order of increasing size.
a) Na+1, K+, S2-, Cl-,
b) Li+, Na+, O2-, S2-, Cl-, Br-
33 Calculate the amount of energy required to separate a Na+ ion and a Cl- ion.
34 The radius of Na+ is 1.16 Å and the radius of Cl- is 1.67 Å. What is the density of NaCl? Note: NaCl forms a simple cubic crystal lattice.
35 Show the Lewis representation for the reaction of Na and S to form Na2S.
36 In the above reaction sodium is OXIDIZED/REDUCED and chlorine is OXIDIZED/REDUCED.
37 Fill in the following energy level diagram for Ni2+.
_____ _____ _____ _____ _____ _____ _____ 4f
_____ _____ _____ _____ _____ 4d
_____ _____ _____ 4p
n=4 ----- _____ _____ _____ _____ _____ 3d
_____4s
_____ _____ _____ 3p
n=3 ----
____ 3s
____ ____ ____ 2p
n=2 ----
____ 2s
n=1 ---- ____ 1s
38 Give the Lewis dot structures for the following.
CH3CH3
O2
N2
CO2
CO32-
39 Give all resonance structures for CO32-.
BF3
NO2
PCl4-1
40 Use bond dissociation energies to calculate the amount of heat given off when one mole of C4H10 burns in oxygen.