How much heat in joules and in calories must be added to a 75.0-g iron block with a specific heat of 0.449 j/g Celsius degree to increase its temperature from 25 degree Celsius to its melting temperature of 1535 degree Celsius?
Please use open stax as a reference answer these questions
CHAPTER 5
6. How much heat in joules and in calories must be added to a 75.0-g iron block with a specific heat of 0.449 j/g Celsius degree to increase its temperature from 25 degree Celsius to its melting temperature of 1535 degree Celsius?
20. An aluminum kettle weighs 1.05 kg
a. What is heat capacity of the kettle?
b. How much heat is required to increase the temperature of this kettle from 23.0 Celsius degree to 99.0 Celsius degree?
c. How much heat is required to heat this kettle from 23.0 Celsius to 99.0 degree Celsius if it contains 1.25 L of water (density of 0.997 g/mL and a specific heat of 4.184 J/g Celsius degree?
20. A 45-g aluminum spoon ( specific heat 0.88 J/g degree Celsius) at 24 degree Celsius placed in 180mL (180g) of coffee at 85 degree Celsius and the temperature of the two become equal.
a. What is the final temperature when the two become equal? Assume that coffee has the same specific heat as water.
b. The first time a student solved this problem she got an answer of 88 degree Celsius. Explain why this is clearly an incorrect answer.
30. When 1.0 g of fructose C6H12O6(s) a sugar commonly found in fruits is burned in oxygen in a bomb calorimeter the temperature of the calorimeter increases by 1.58 degree Celsius. If the heat capacity of the calorimeter and its content is 9.90 kJ/ degree Celsius what is q for this combustion?
46. How much heat is produced by combustion of 125 g of methanol under standard state conditions?
64. Calculate (it looks like a slated triangle next to this equation) H298 (there is a degree sign next to the h) for the process Zn(s) + S(s)+ 2O2(g)——->ZnSO4(s)
from the following information
Zn(s) + S(s)——-> ZnS(s) (slated triangle)H298 (there is a degree sign next to the h)= -206.0kJ
Zns(s) + 2O2(g)——>ZnSO4(s) (slated triangle)H298 (there is a degree sign next to the h)= -776.8kJ
Chapter 6
14. Answer the following questions about a Blu-ray laser
a. The laser on a Blu-ray player has a wave length of 405nm. In what region of the electromagnetic spectrum is this radiation? What is its frequency?
b. A Blu-ray laser has a power of 5 milliwatts (1 watt= 1 J s-1) How many photons of light are produced by the laser in 1 hour?
c. The ideal resolution of a player using a laser (such as a Blu-ray player) which determines how close together data can be stored on a compact disk is determined using the following formula Resolution = 0.60(NA) where A is the wavelength of the laser and NA is the numerical aperture. Numerical aperture is a measure of the size of the spot light on the disk ; the larger the NA the smaller the spot. In a typical Blu-ray system NA= 0.95 if the 405-nm laser is used in a Blu-ray player, What is the closest that information can be stored on a Blu-ray disk?
d. The data density of a Blu-ray disk using a 405-nm laser is 1.5×107 bits mm-2. Disks have an outside diameter of 120mm and a hole of 15-mm diameter. How many data bits can be contained on the disk? If a Blu-ray disk can hold 9,400,000 pages of text how many data bits are needed for a typed page?
20. Using the Bohr model , determine the lowest possible energy in joules for the electron in the Li2+ ion.
26. Using the Bohr model, determine the energy in joules of the photon produced when an electron in a He+ ion moves from the orbit with n=5 to the orbit with n=2
32. What are the allowed values for each of the four quantum numbers n, l, ml, and ms?
42. State the Heisenberg uncertainty principle. Describe briefly what the principle implies
54 Using complete subshell notation (1s2 2s2 2p6, and so forth) predict the electron configuration sof the following ions.
a. N3-
b. Ca2+
c. S-
d. Cs2+
e. Cr2+
f Gd 3+
