T4.pdf

A wavelength of 1000 nm is associated with an electronic event. What is the frequency of this radiation? What is the energy of this radiation in terms of Joules per photon? What is the energy of this radiation in terms of Joules per mole? Can this radiation be detected by a normal human eye? If not then specify and justify whether the radiation would appear in the infra red or ultra violet regions of the electromagnetic spectrum. Radiation of this wavelength appears in the Infra Red region, and can not be detected by the eye.
Benzoyl peroxide, C 14 H 10 O 4 , is commonly used in medicinal preparations. Write a balanced chemical equation for the combustion of benzoyl peroxide. When 3.562 g of benzoyl peroxide are combusted in oxygen gas, a quantity of 95.6 kJ of heat is evolved in a constant pressure process. Determine the enthalpy of formation for benzoyl peroxide. ? q(kJ / mole) =  Write a balanced thermochemical equation for the enthalpy of formation of benzoyl peroxide. Construct a balanced chemical equation for the following oxidation-reduction reaction occurring in a basic solution: What volume of a 0.155 M calcium zincate solution, Ca 2 ZrO 4 , will be needed to react with 1.749 grams of sodium sulfate, Na 2 SO 4 , according to this reaction? moles Ca 2 ZrO 4 = moles Na 2 SO 4 [ C. F. ]  1 mole   4 mole  142 g / mole  1 mole  2 mole Suppose 245 grams of steam at 115 degrees Celsius, is allowed to mix with 900 grams of ice at –25 degrees Celsius. What is the final state and temperature of the mixture? cool 245 grams from 115 to 100 degrees C, q = ( .
warm 900 grams from -25 to 0 degrees C, q = ( .
Net heat is negative, too much heat has been removed from the system to achieve this condition. It must be retur ned (added) to the 1145 grams of liquid water at zero degrees C. + 318,130 J = (4.18 J/g − deg)(1145 g)(T − 0) Consider a process involving hydrogen atom in which the electron jumps to the second shell from the seventh shell. a. Calculate the energy of this process in Joules per photon. ∆E =− 5.00x10-19 Joules / photon (exothermic) {Although Energy can be positive (endothermic) or negative (exothermic), Calculate the wavelength of radiation associated with this process. Can this radiation be detected by the human eye? If so, then what color would be observed? Barely, if at all. 400 nm is at about the limit of the visible range. If detectable then the color would be blue/violet. The following data is taken from a calorimetric e xperiment involving combustion of 3.941 g of sucrose, C 12 H 22 O 11 : Initial Temperature of Calorimeter = 19.71 degrees Celsius. Final Temperature of Calorimeter after combustion reaction = 23.26 degrees Celsius. Heat Capacity of Calorimeter = 18.3 kJ / degree. q , ∆E, work, ∆H In this reaction 12 moles of gas are formed for every 12 moles of gas reacted. So ∆n = 0 Utilize the thermochemical equations listed below to determine the enthalpy of (1) B + 1 / 2 O
(2) B H
(3) H
(4) B O

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