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# jewls

• ### Chemistry equilibrium question?

A sample of nitrosyl bromide (NOBr) decomposes according to the equation

2NOBr(g)⇌2NO(g)+Br2(g)

An equilibrium mixture in a 5.00-L vessel at 100 ∘C contains 3.25g of NOBr, 3.03g of NO, and 8.07g of Br2.

Kc=0.118

a) What is the total pressure exerted by the mixture of gases

b) What was the mass of the original sample of NOBr

• ### Kinetics question using activation energy?

I have been using the equation K=Ae^(-Ea/RT) and can't seem to get the right answer for A. Is there anyway you could help me figure out how to solve for A?

The temperature dependence of the rate constant for the reaction is tabulated as follows:

Temperature (K) k(M−1s−1)

600 0.028

650 0.22

700 1.3

750 6.0

800 23

Ea=130 KJ/M

Calculate A

• ### Chemistry kinetics/rates problem help?

I'm having difficulties setting these problems up and was wondering if anyone could offer me some help on figuring out the answers. Thanks!

The first-order rate constant for the decomposition of N2O5,

2N2O5(g)→4NO2(g)+O2(g),

at 70∘C is 6.82×10−3s−1. Suppose we start with 2.35×10−2mol of N2O5(g) in a volume of 1.5L .

a) How many moles of N2O5 will remain after 5.2min ?

b)How many minutes will it take for the quantity of N2O5 to drop to 1.4×10−2mol ?

c)What is the half-life of N2O5 at 70∘C?

• ### calculate the number of moles Hg estimated to be in the atmosphere today.?

Mercury is a liquid at room temperature and pressure, but its vapor is present in the atmosphere from natural sources, such as volcanoes, and from human ("anthropogenic") activities such as coal burning and gold mining. Elemental Hg becomes extremely toxic when oxidized to Hg(I) or Hg(II) compounds.

Geological records suggest that before the Industrial Revolution began in 1750, the baseline level of atmospheric Hg was 35 ppb (parts per billion, by volume, or 35 L Hg for every 109L of air); current estimates are 245 ppb.For an estimated atmospheric volume of 51×1012m3, calculate the number of moles Hg estimated to be in the atmosphere today.

I would appreciate any help on this problem. The answer I keep getting is apparently wrong, and I don't know how else to approach the problem.

• ### Chemistry help. What is the characteristic wavelength?

An electron is accelerated through an electric potential to a kinetic energy of 18.2keV .

What is its characteristic wavelength?

[Hint: Recall that the kinetic energy of a moving object is E=1/2mv2, where m is the mass of the object and v is the speed of the object.]

I am having trouble figuring out how to approach this problem. I would very much appreciate some help. Thanks!

• ### Have You Ever Had A Broken Heart????

Have you ever had you heart broken? What happened and how did you deal?

• ### whats your idea of a great date?

in your opinion what would you consider to be the perfect date???

• ### What is the best type of digital camera to buy?

Im planning on getting a new digital and was wondering what kind you think is the best.

• ### Should I or shouldnt I?

Mk. So theres this guy i really like and he told my bff that he liked me too, which made sense cus he was always sending my cute flirty text messages. Alittle over a week ago he sent me one that said he heard a rumor bout me an him an to text him back, but i didnt an he sent me another saying not to expect to talk to him then. It been a week and neither of us have tried to talk to the other, an im wondering who thinks i should make the first move and text him. so yes or no??

• ### What are some good scary movies?

Me and a bunch of friends want to watch scary movies on holloween and i was wondering if anyone has some recomendations. I want to watch the scariest you can think of. thanx.

• ### can u move ur arm if u have a seperated shoulder?

I think i have a seperated shoulder and am getting x rayed in the morning but am wondering r u able to like move ur arm if u have 1?

• ### good books?

what are some good books anyones read? I prefrer murder mysteries but whould read w/e and i read novels adult ones. any recomendations?

mk so theres this girld and shes my best friend well i thought she was but now im not so sure a thing happened with this guy and me and this other girl how acted like she was my friend told him i said some stuff that i really didnt say and like i confronted her bout it and she was like i never said that u said that and my best friend heard her say it and now for some reason she says she believes the other girl just cus she swore on the bible and shes not even rligous(the girl that told the lies) I swear its not a lie i would never tell my best friend a lie or the guy that i care so much about i live for that kid nd he wont believe me and i dont want to lose me bffl. Why wont she believe me? Im just so confused right now and its caused so much stress that i cant eat and when i do i sometimes end up throwing it up. You have to help. What do I do?