Henrys Law Example Problem

Henrys Law Example Problem Henrys law is a gas law  formulated by the British chemist William Henry in 1803. The law states that at a constant temperature, the amount of dissolved gas in a volume of a specified liquid is directly proportional to the partial pressure of the gas in equilibrium with the liquid. In other words, the amount of dissolved gas is directly proportional to the partial pressure of its gas phase. The law contains a proportionality factor that is called Henrys law constant. This example problem demonstrates how to use Henrys law to calculate the concentration of a gas in solution under pressure. Henrys Law Problem How many grams of carbon dioxide gas is dissolved in a 1 L bottle of carbonated water if the manufacturer uses a pressure of 2.4 atm in the bottling process at 25  °C?Given: KH of CO2 in water 29.76 atm/(mol/L) at 25  °CSolutionWhen a gas is dissolved in a liquid, the concentrations will eventually reach equilibrium between the source of the gas and the solution. Henrys law shows that the concentration of a solute gas in a solution is directly proportional to the partial pressure of the gas over the solution.P KHC where:P is the partial pressure of the gas above the solution.KH is the Henrys law constant for the solution.C is the concentration of the dissolved gas in solution.C P/KHC 2.4 atm/29.76 atm/(mol/L)C 0.08 mol/LSince we have only 1 L of water, we have 0.08 mol of CO. Convert moles to grams: mass of 1 mol of CO2 12(16x2) 1232 44 g g of CO2 mol CO2 x (44 g/mol)g of CO2 8.06 x 10-2 mol x 44 g/molg of CO2 3.52 gAnswer There are 3.52 g of CO2 dissolved in a 1 L bottle of carbonated water from the manufacturer. Before a can of soda is opened, nearly all the gas above the liquid is carbon dioxide. When the container is opened, the gas escapes, lowering the partial pressure of carbon dioxide and allowing the dissolved gas to come out of solution. This is why soda is fizzy. Other Forms of Henrys Law The formula for Henrys law may be written other ways to allow for easy calculations using different units, particularly of KH. Here are some common constants for gases in water at 298 K and the applicable forms of Henrys law: Equation KH = P/C KH = C/P KH = P/x KH = Caq / Cgas units [Lsoln atm / molgas] [molgas / Lsoln atm] [atm molsoln / molgas] dimensionless O2 769.23 1.3 E-3 4.259 E4 3.180 E-2 H2 1282.05 7.8 E-4 7.088 E4 1.907 E-2 CO2 29.41 3.4 E-2 0.163 E4 0.8317 N2 1639.34 6.1 E-4 9.077 E4 1.492 E-2 He 2702.7 3.7 E-4 14.97 E4 9.051 E-3 Ne 2222.22 4.5 E-4 12.30 E4 1.101 E-2 Ar 714.28 1.4 E-3 3.9555 E4 3.425 E-2 CO 1052.63 9.5 E-4 5.828 E4 2.324 E-2 Where: Lsoln is liters of solution.caq is moles of gas per liter of solution.P is partial pressure of the gas above the solution, typically in atmosphere absolute pressure.xaq is mole fraction of the gas in solution, which is approximately equal to the moles of gas per moles of water.atm refers to atmospheres of absolute pressure. Applications of Henrys Law Henrys law is only an approximation that is applicable for dilute solutions. The further a system diverges from ideal solutions ( as with any gas law), the less accurate the calculation will be. In general, Henrys law works best when the solute and solvent are chemically similar to each other. Henrys law is used in practical applications. For example, it is used to determine the amount of dissolved oxygen and nitrogen in the blood of divers to help determine the risk of decompression sickness (the bends). Reference for KH Values Francis L. Smith and Allan H. Harvey (Sept. 2007), Avoid Common Pitfalls When Using Henrys Law, Chemical Engineering Progress  (CEP), pp. 33-39

How to Conjugate the Verb Potere in Italian

How to Conjugate the Verb Potere in Italian Talking about what you can and can’t do is a basic cornerstone of everyday conversation, so you’re going to want to know the verb â€Å"potere† and its conjugations inside and out. What’s more, it’s an irregular verb, so it doesn’t follow the typical -ere verb ending pattern. Below you’ll find all of its conjugation tables as well as examples. Some definitions of â€Å"potere† include: To be able toCanMay What to know about potere: It’s a transitive verb, so it takes a direct object.When it’s used as a modal verb, it usually takes the auxiliary verb required by the verb it is paired with.The infinito is â€Å"potere†.The participio passato is â€Å"potuto†.The gerund form is â€Å"potendo†.The past gerund form is â€Å"avendo potuto†. INDICATIVO/INDICATIVE Il presente io posso noi possiamo tu puoi voi potete lui, lei, Lei pu loro, Loro possono Esempi: Possiamo andare al Colosseo? - Can we go to the Coliseum?Mi puà ² aiutare? - Can you help me? (formal)Loro possono fare tutto quello che vogliono. - They can do whatever they want. Il passato prossimo io ho potuto noi abbiamo potuto tu hai potuto voi avete potuto lui, lei, Lei ha potuto loro, Loro hanno potuto Esempi: L’anno scorso ho guadagnato un sacco di soldi, cosà ¬ ho potuto comprare una nuova macchina!   - Last year I earned a bunch of money, so I was able to buy a new car.Non ti abbiamo potuto aspettare. - We couldn’t wait for you. L’imperfetto io potevo noi potevamo tu potevi voi potevate lui, lei, Lei poteva loro, Loro potevano Esempi: C’erano tante lingue tra cui potevo scegliere ad imparare, perà ² alla fine, ho scelto l’Italiano. - There were a lot of languages I could have chosen to learn, but in the end, I chose Italian.Quando mi ha raccontato la storia, non ci potevo credere! - When he told me the story, I couldn’t believe it! Il trapassato prossimo io avevo potuto noi avevamo potuto tu avevi potuto voi avevate potuto lui, lei, Lei aveva potuto loro, Loro avevano potuto Esempi: Non avevo mai potuto studiare all’estero. - I had never been able to study abroad.Era il massimo che loro avevano potuto fare. - It was the maximum they had been able to do. Il passato remoto io potei/potetti noi potemmo tu potesti voi poteste lui, lei, Lei pot/potette loro, Loro poterono/potettero Esempi: L’esercito di Napoleone non potà © sopravvivere nella campagna sperduta della Russia durante l’inverno. - Napoleon’s army couldn’t survive in the hopeless countryside of Russia during the winter.I nostri bisnonni non poterono/potettero viaggiare dapertutto come possiamo attualmente. - Our great-grandparents couldn’t travel anywhere like we can now. Il trapassato remoto io ebbi potuto noi avemmo potuto tu avesti potuto voi aveste potuto lui, lei, Lei ebbe potuto essi, Loro ebbero potuto Esempi: Quando i bambini ebbero potuto, mangiarono le caramelle. - When kids were could, they ate candies.Continuai a ripetere la stessa frase, finchà ¨ Mary ebbe potuto capire. - I kept repeating the same sentence, until Mary was able to understand. TIP: This tense is rarely used, so don’t worry too much about mastering it. You’ll find it in very sophisticated writing, and that’s about it. Il futuro semplice io potr noi potremo tu potrai voi potrete lui, lei, Lei potr loro, Loro potranno Esempi: Quando tornano a casa, potremo andare a cena. - When they return home, we will be able to go to dinner.Potranno guardare il film con noi? - Will they will be able to watch the movie with us? Il futuro anteriore io avr potuto noi avremo potuto tu avrai potuto voi avrete potuto lui, lei, Lei avr potuto loro, Loro avranno potuto Esempi: Avevi il pomeriggio libero, avrai potuto dedicarti a te stessa! - You had a free afternoon, you must have dedicated time to yourself! Come avrete potuto notare avete passato l’esame! - As you will have noticed, you passed the exam! CONGIUNTIVO/SUBJUNCTIVE Il presente io possa noi possiamo tu possa voi possiate lui, lei, Lei possa loro, Loro possano Esempi: Penso che, dato che ho gi il visto, io possa vivere in Italia per un anno. - Given that I already have a visa, I think that I live in Italy for a year.Sono contenta che tu possa venire con noi. - I’m happy that you can come with us. Il passato io abbia potuto noi abbiamo potuto tu abbia potuto voi abbiate potuto lui, lei, Lei abbia potuto loro, Loro abbiano potuto Esempi: Sono felice che Leonardo abbia potuto aiutarti. - I’m happy that Leonardo was able to help you.Non siamo sicuri se abbiano potuto trovare la scuola. - We’re not sure if they were able to find the school. L’imperfetto io potessi noi potessimo tu potessi voi poteste lui, lei, Lei potesse loro, Loro potessero Esempi: Speravo che lui potesse aiutarmi! - I hoped that he would be able to help me!Credeva che potesse cercare un nuovo lavoro senza problemi. - She believed she would be able to find a new job without problems. Il trapassato prossimo io avessi potuto noi avessimo potuto tu avessi potuto voi aveste potuto lui, lei, Lei avesse potuto loro, Loro avessero potuto Esempi: Vorrei che loro avessero potuto vederci! - I wish they could have seen us!Loro sono entrati alla festa, senza che la padrona di casa avesse potuto fare niente. - They showed up at the party, without the owner of the house could have done anything. CONDIZIONALE/CONDITIONAL Il presente io potrei noi potremmo tu potresti voi potreste lui, lei, Lei potrebbe loro, Loro potrebbero Esempi: Potrei andarci, perà ² non voglio. - I could go there, but I don’t want to.Lei vuole viaggiare? Potrebbe andare in Francia e fare WOOFing. - She wants to travel? She could go to France and do WOOFing. Il passato io avrei potuto noi avremmo potuto tu avresti potuto voi avreste potuto lui, lei, Lei avrebbe potuto loro, Loro avrebbero potuto Avrei potuto dirtelo, ma ho pensato non fossi pronta. - I could have told you, but I thought you weren’t ready.Avrebbe potuto scrivere almeno una e-mail! - She could have written at least one e-mail!