If you want to make a blue LED- what is the range of possible band gap.docx

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If you want to make a blue LED, what is the range of possible band gaps that your semiconductor must have in units of eV? Name at least one semiconductor that has a band gap in this range, it can be either an elemental or a compound semiconductor. Solution blue light has a wavelength ranging form 450 nm to 500 nm the band gap of the semiconductor required to emit blue light is given by energy = hC / wavelength So, it is 2.48 eV to 2.75 eV the range of possible bandgaps is 2.48 eV to 2.75 eV Few semiconductors that has a band gap in this range and are being used for blue LED\'s are Zinc selenide (ZnSe) Indium gallium nitride (InGaN) Silicon carbide (SiC) as substrate .

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In an aqueous solution of 0.020 M HCl under standard conditions (T=25 C).... (Show & explain work) i) What is the H + concentration? ii) What is the pH of the solution? What about the pOH? iii) What is the OH - of the solution? Solution i) [H+] = [HCl] = 0.020 M Answer: 0.020 M ii) use: [OH-] = Kw/[H+] Kw is dissociation constant of water whose value is 1.0*10^-14 at 25 oC [OH-] = (1.0*10^-14)/[H+] [OH-] = (1.0*10^-14)/(2*10^-2) [OH-] = 5*10^-13 M use: pH = -log [H+] = -log (2*10^-2) = 1.699 use: pOH = -log [OH-] = -log (5*10^-13) = 12.301 Answer: pH = 1.70 pOH = 12.30 iii) As calculated above, [OH-] = 5.0*10^-13 M .

In an aqueous solution of 0-020 M HCl under standard conditions (T-25.docx

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In a preparation for a synthetic plant hormone I experiment. 1. Give an arrow pushing mechanism for the reaction performed. 2. If phenol (or phenolate) was substituted for 4-chlorophenol what product would be obtained from the reaction. Explain Solution 2) The soluble properties of compounds differ. Phenols are acidic in nature. When sodium hydroxide a base is added, the acidic components gets deprotonated. It becomes an ionic salt which is soluble in water. The deprotonated salt will be in an aqueous layer form. As phenol is a stronger acidic solution, it requires a strong base of aqueous sodium hydroxide to deprotonate its structure. Hence 4-chlorophenol gets deprotonated rapidly in the presence of NaOH. If phenol is used as substrate, sodium phenoxide will be formed with water as the by-product .

In a preparation for a synthetic plant hormone I experiment- 1- Give a.docx

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In 2012 Tony invests $35,000 in an activity for which he is not a material participant. Tony has no other sources of income. Tony\'s losses from the activity are as follows: Income/(Loss) 2012 ($25,000) 2013 ($15,000) 2014 $50,000 Calculate Tony’s deductible loss, basis, and any losses suspended under the at-risk and/or passive activity loss rules each year. Solution As Tonu is not a material participant, the basis will be Year 1 35000 Year 2 10000(35000-25000) Year 3 -5000(10000-15000) The risk will be 2012 35000 2013 10000 2014 0 .

In 2012 Tony invests $35-000 in an activity for which he is not a mate.docx

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In 1985 Ted Thomas took $6,000 of his savings, borrowed another $4,000 from his best friend, and opened a bike rental business in Vienna, VA, adjacent to the Washington & Old Dominion Trail (W&OD) that goes from Purcellville to Old Town Alexandria (45 Miles) and connects to the Mt Vernon Trail (18 Miles) and ends at George Washington Solution Ans 2. Ted would need an office (1) information system that Tded could use to perform day to day office function such as creating distributing documents for the office or personnel, send messages through email instead of using the phone all the time to his other stores, for accounting purposes as well as storing employee information, and building databases for his business; (2) a transaction process system to maintain Teds .

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In 1993 the 101st International Olympic Committee met in Monaco to select the 2000 Winter Olympics site. The cities in the running were Beijing (B), Berlin (L), Istanbul (I), Manchester (M), and Sydney (S). Suppose we look at their voting preferences. Find the results of the election using the Hare method. Just after the third vote, one of the committee members voting for Manchester was accused of cheating and was disqualified. Because of that scandal, one member admitted she was voting insincerely, and changed her vote from Manchester to Sydney. What is the result of using the Hare method? Do the results of parts (a) and (b) violate any of the fairness criteria? Yes no if the last answer positive, which fairness criterion is being violated? Monotonicity Criterion Irrelevant Alternatives Criterion Condorcet Criterion None Majority Criterion Solution L no none .

In 1993 the 101st International Olympic Committee met in Monaco to sel.docx

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Implement a Linked List as a subclass of the abstract List class. Make sure it works in all these cases: 1. insert(element, 0) should work if head is null 2. insert(element, 0) should update head 3. remove(0) should update head 4. Copying an empty list should work Solution import java.util.LinkedList; import java.util.List; public class listest { public static void main(String[] args) { List l=new LinkedList(); l.add(0, 51); System.out.println(\"Element at 0: \"+l.get(0)); l.add(0, 23); System.out.println(\"Element at 0: \"+l.get(0)); l.remove(0); System.out.println(\"Element at 0: \"+l.get(0)); List l1=new LinkedList(); l1=l; System.out.println(\"Element at 0 in new list:\"+ l1.get(0)); } } .

Implement a Linked List as a subclass of the abstract List class- Make.docx

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imagine a simple economy of freedonia that uses gold as its currency ( only gold, not gold backed paper). suppose that Freediona finds itself deeply in debt and that its creditors who all live in the country of Sylvania demand the repayment of debt in gold. what is likely to happen to the economy? (answer it as specific as possible. explain ti ) Solution In the emerging but scattered country of Freedonia, the people decided one day that they wanted to band together to protect their freedom as a nation, their individual rights, and to grow their economy together. They establish a constitution to form a government, courts, police, an army, and the ability to empower their government to build roads and infrastructure needed for defense, well-being, and commerce. They also wanted a way to provision for their elderly and needy. With their constitution in place, they excitedly asked for volunteers to come and perform all the work needed in the new government .

imagine a simple economy of freedonia that uses gold as its currency ( (1).docx

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