Chapter 5
State whether the kinetic energy of the underlined object increases or decreases as a result of the change described:
a. a golf ball lands on a green
b. a tennis ball is served
c. a car stops at a red light.
a. decreases
b. increases
c. decreases
A single wind turbine can generate enough electrical energy in a month to power 543 homes. This is the equivalent of 2.05×10^12 J of energy. How many kilowatt-hours of electrical energy per month does this wind turbine represent? (1 J = 2.778×10^-7 kWh)
5.69×10^5 kWh
A local FM radio station broadcasts at a frequency of 100.8 MHz. Calculate the wavelength at which they are broadcasting.
Wavelength = 2.974 m
Using only the periodic table arrange the following elements in order of increasing ionization energy: antimony, indium, strontium, tellurium
strontium, indium, antimony, tellurium
In the laboratory, a student finds that it takes 69.3 Joules to increase the temperature of 12.8 grams of solid iron from 24.3 to 37.5 degrees Celsius.
What is the specific heat of iron?
0.410 J/gC
A chemical reaction is run in which 751 Joules of heat are absorbed and the internal energy changes by +999 Joules. Calculate w for the system.
248 J
A 500.-mW krypton laser produces a beam of red light with a wavelength of 647.1 nm (6.471×10^-7 m). (1 W = 1 J s-1).
a. Calculate the energy carried by each photon
b. Calculate the number of photons emitted by the laser per second.
a. 3.070×10^ -19 J
b. 1.63×10^18 photons s-1
Orbital Energy Diagram (see slides)
arrows (See slides)
The following thermochemical equation is for the reaction of hydrogen(g) with ethylene(g) to form C2H6(g):
H2(g) + C2H4(g) --> C2H6(g) H = -137 kJ.
How many grams of H2(g) would have to react to produce 28.9 kJ of energy?
0.425 g
The reaction of carbon monoxide(g) with oxygen(g) to form carbon dioxide(g) proceeds as follows:
2 CO(g) + O2(g) -> 2 CO2(g)
When 6.16 grams of CO(g) react with sufficient O2(g), 62.2 kJ of energy are evolved. What is the value of H for the chemical equation given?
-566 kJ
Which of the following combinations of quantum numbers are allowed for an electron in a one-electron atom?
A. n = 5 , l = 0 , m = 1 , ms = -½
B. n = 6 , l = 4 , m = 2 , ms = -½
C. n = 2 , l = 0 , m = 0 , ms = -½
D. n = 3 , l = 3 , m = -1 , ms = -½
B. n = 6 , l = 4 , m = 2 , ms = -½
C. n = 2 , l = 0 , m = 0 , ms = -½
Calculate the de Broglie wavelength of the following.
(a) An electron moving at a speed of 943 m s-1.
(b) A proton moving at a speed of 943 m s-1.
(c) A bullet with a mass of 8.60 grams moving at a speed of 911 m s-1.
(a) 7.71×10^-7 m
(b) 4.20×10^-10 m
(c) 8.46×10^-35 m
Enthalpy (see slides)
-409.6 kJ/mol
Enthalpy (see slides)
Answer on slides
(a) The position of an electron is known to be within 8.78 Å (8.78×10^-10 m). What is the minimum uncertainty in its velocity?
(b) Repeat the calculation of part (a) for a fluorine atom.
(a) 6.59×10^4 m/s
(b) 1.90 m/s
Pauli Exclusion Principle (See slides)
See slides
Bomb Calorimetry (see slides)
-2.919x10^3 kJ/mol C6H12O6
Coffee Cup Calorimetry (see slides)
0.401 J/gC
Bohr Model (see sldies)
Arrows (see sldies)
a. Calculate the energy for the transition of an electron from the n=7 level to the n=5 level of a hydrogen atom.
b. Is this an absorption or an emission process?
a. -4.269 x 10^-20 J
b. emitted