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What is Kekule's law?

A compound is substance made up of constant continuous composition... Wat does this mean??

How can we factorize cubic polynomials? e.g. y3+ 2y2+ y+ 1

A circular disc of radius 3 cm is being heated. Due to expansion, it's radius increases at the rate of 0.05 cm/s . Find the rate at which it's area is increasing when radius is 3.2 CMS Some one please explain the way this sum is done with the help of calculus

Hi, This is my first post and i'm stuck on this question. I cant figure out how to determine the concentration of unknown water samples using known specific gravities. What methods i.e formulas do i need to use. Any help would be appreciated. Thanks. Determination of the salinity of three estuarine water samples.pdf

I'm looking for some help on a problem that I am doing in my Biochemical Separations class. The question is as follows: An Alfa Laval centrifuge (model BTPX 205) is being used for the harvesting of baker’s yeast suspensions. The cells were used to express a human protein which is present in the cytoplasm in the form of inclusion bodies 0.3 to 0.7 um in diameter with a density of 1.3 g/ml. The cells were first collected by centrifugation, resuspended in saline solution and disrupted in a high pressure homogenizer. By running the centrifuge at the proper speed the inclusion bodies may be separated from the cell debris. (a) What effective area (Σ) is necessary for baker’s …

How would you name this compound? I have taken a guess and named is: 3,4-ethyl-2-methylhexane But can we name it so that it has two substituents?

I have been stuck on the problem shown below. I've made many attempts but the answer will not show itself! I'm solving for d

There are dozens of essay checkers, that I have used, and not all of them are really.....effective. Are there are good, free essay checkers?

Hello, How would I go about finding the number of atoms in an element sample, given the density. I have found the volume and mass of my sample and presume I should work it like such: [Number of atoms] = [Avogadro's Number] * (density) * volume/(atomic weight) In my case, I have aluminum foil of 27g, 27g/mol, and 10 cm3 When using the equation above I end up with six atoms? I suppose the error is in the equation(but I don't know) Thanks

Well i believe computer science is. I am writing an essay on why it is considered a science. I have found great peered reviewed articles on why it is but I cannot find a single article on why computer science is not a science. I need help in finding these articles. if anyone would be so kind in just point me in the right direction.

Hi all, I have to do some tests on my fermentation project today and after I am expected to write a SWOT analysis.This is something we have never done, and we haven't really talked about it in lectures. Does anyone have any pointers on things to include? I will briefly explain what the project is about in case that will help direct suggestions. It's an independent fermentation project. I decided to put different amounts of both garlic cloves and minced garlic in sealed jars of raw honey to see if I could have any impact on pH. The reason for this is that sometimes honey has Clos clostridium botulinum spores, and they favour a certain pH. I was hoping to see some variat…

I have to prepare drug loaded nanoparticles as following : Doxorubicin loaded nanoparticles are synthesized as following method... 500 μL of 10 mg/mL Doxorubicin in acetone was added into 2 mL of 10 mg/mL PLGA in acetone. The resulting solution was then precipitated into 10 mL of water. The solution was spun to evaporate acetone for 3 hr. The final nanoparticles solution was washed to remove unencapsulated drug. The encapsulated drug in nanoparticles was quantified and the amount of drug is 2 mg from 10 mL final nanoparticles solution. So how to calculate the drug input (%), loading yield (%) and encapsulation efficiency (%). I'm very new in this area and I'm still imp…

I was needing a little help balancing an equation: I'm exploring various ways of making NH4NO3. (And if your contribution is to tell me I'll end up on some watch list for even mentioning the compound, please keep your ridiculous ill-informed paranoia to yourself - if I was a terrorist, I'd be buying NH4NO3 fertiliser, not making a few grams!). Having successfully mixed NaHSO4 with NaNO3 and neutralised with NH3, I balanced to give Na2SO4 + NH4NO3. So I replaced the nitrate salt with KNO3, and expected an eqimolar precipitate of Na2SO4 and K2SO4 (and of course the NH4NO3 in solution). However, I've tried a few equation balancers online, and they tell me it's an "impo…

So to eject a proton from a Fluorine nucleus there is a photon needed with 7,99485 MeV of energy going in the right direction to get absorbed by a proton of a Fluorine nucleus ? To calculate the wavelength of the photon there is this equation: or which brings up to a wavelenght of 1,550998455 * 10^-07 micrometer, multiplied by a 1000 to give nanometers it is 1,550998455 * 10^-04 nanometer which is 0,0001550998455 nanometer. Is this correct ? (Please correct me if I am saying anthing wrong)

HI, this is my first post here. I am studying year 11 physics in high school in Australian (VCE) curriculum and quite enjoy physics, except for one unit we did, relating to matter, radiation, half lives and the big bang. Day after tomorrow is my mid year physics exam and I feel confident about the other two areas on the exam (electric circuits and thermodynamics) but an understanding of the "matter" topic continues to elude me, which is reflected in the scores of past tests. I got 87% and 83% for my thermodynamics and electric circuits tests respectively but only scored 54 for my Matter test. We've been provided with a list of things we have to study for the exam and if …

I know it has something to do with U-Values but i'm not sure what everything stands for or how to use it. Please help...

Hello, I need to finish that for tonight and I dont know what to use and what to do. If anyone can help me that would be great. The average base salary for a store manager (Wal-Mart) in Sacramento, is $68,000, and the average base salary for a store manager (Wal-Mart) in San Francisco,is $78,000. Assume that salaries are normally distributed, the standard deviation for store managers in Sacramento is $20,000, and the standard deviation for store managers in San Francisco is $22,000. (A) What is the probability that a store manager in Sacramento has a base salary in excess of $100,000? (B) What is the probability that a store manager in San Francisco has a…

Consider only "given" and "to prove" and any of the two figures. AB is not equal to AC.

What is the difference between the two? I heard that a monatomic ion is only one atom but how could this be called an ion if it is only atom that has not shared electrons?

Hi friends, I have a problem from my Geography course that my notes do not tell me how to solve so hopefully you guys will be able to help me out! Anyway, the problem is "The dew point temperature is 55°F and the air temperature is 75°F. Q1: What is the relative humidity? Q2: What is the relative humidity if the temperature were to drop to 50°F overnight?" Not looking for answers, but would like assistance in learning how to solve this problem. Thanks!

I have an exam coming up and have some past exam papers to guide my revision. But i don't have any answers, so i thought i would post some of the questions here with my answers and see if anyone wants to have a crack at them too and check my answers. I'm aiming for at least one a day. This question concerns a particle in a one-dimensional infinite square well, described by the potential energy function: [latex] V(x) = \begin{cases}0 & \mbox{if} \; 0\leq x \leq L \\\infty & \mbox{otherwise}\end{cases} [/latex] The normalized energy eigenfunctions for the particle in the well take the form: [latex] \psi_n(x) = \begin{cases}\sqrt{\frac{2}{L…

I have a glass of water with a PH of 7. I put a Plant in the water and mashed the Plant up. The PH of the water is now 6. What is the PH of the Plant? Is there a formula I can use to calculate the change?

Was practicing naming organic compounds. Made this and found out it is called 1,1-dimethylaminoethane. Question: Why isn't it called 1,5-dimethyldiaminoethane? Thank you in advance.

True or False