Homework Help

The question is find the temperature for the normal boiling point in the phase diagram of the pure substance above. I thought the answer would be 90 C because that is where the liquid/gas line hits 1 atm. But apparently the answer is 44 C. Why?

The pH of a 0.10 M solution of an aqueous weak acid (HA) is 4.00. The Ka for the weak acid is..... I know the expression for Ka is [H+][A-]/[HA] But I don't know what to do next.

Question : If you are given the total mass of clips in each four containers and without knowing how many numbers of clips are there, how will you find out the mass of one clip? First container: 7.5 g Second container: 20 g Third container: 50 g Fourth container: 125 g I have no idea how this relates to our topic in class. Our topic in class is about the Millikan Oil drop and J.J thompson's charge-to-mass ratio.

having some trouble with this. carbon disulfide is a covalent molecule that has a melting temperature of -110.8 C°. at room temperature 25C° and pressure 1 atmosphere carbon disulfide is a liquid. under the same conditions aluminium sulphide, an ionic compound , is a solid with a melting temperature of 1110 C° write the chemical formulas of these two substances: so what i did is this: Cs2+ Al2S3 but there is no chemical formula right? or I'm ai wrong?

[OH - ] = 5.97 X 10e-8 M wouldn't [H+] = 5.97 X 10e-6?

If the rock contained no carbonate other than CaCO3, what was the percent of CaCO3 by mass in the limestone? CaCO3 + 2HCl ----> CaCl2 + CO2 + H2O

I've been studying analytical chemistry for the past few days, and I don't really understand the basis on how general chromatography works. I think I've worked up a basic understanding of it, but I'm not sure if I'm completely right or not. Assume that this is column chromatography and the sample is a solvent. From what I understand It's a way to separate compounds by using a mobile phase and a stationary phase. The mobile phase is what the compound is dissolved into. Once the mobile phase has the compound, it carries it through the column, which has a thin layering of the stationary phase around it. As the mobile phase passes through the column, parts of the compou…

Hi, I have to replay the results in this paper, I have some doubts in the section IIIA, which shows the ellipsoid uncertainty model. I don't understand the equation (at the end of page 5): (1) [latex]a(\theta)[/latex] is a 14-element column vector, [latex]\Sigma[/latex] is a 14-by-14 - matrix, [latex]\bar{a}[/latex] is a 14-element column vector, so I can not understand how they performed this equation. I tried to explain it based on other equations: The quadratic form Q shows that P must be a 210-by-210 - matrix: (2) But the equation at the end of the page shows that [latex]\bar{P}[/latex] is a 14-by-14 - matrix (P and [latex]\bar{P}[/latex] must have the same…

hi guys this is an image of the rear wheel of a push bike going into a corner as well as what i think are relevant forces, i need to calculate the moments or torque at A (the contact patch) and B (the hub centre) this is to calculate the force on the left hand side of the frame and right hand side of the frame while in a corner Fsr = the force going through the suspension Fc = lateral cornering forcer on the rear wheel phi = lean angle MG = mass & gravity t = the cross sectional radius of the tyre i can and have calculated the above parameters through lot of prior equations that take into account the wheelbase, velocity, friction, radius of the turn ect. but i think …

For one of our assignments, there is a hypothetical experiment in which the eggs of clams from different populations are attempted to be fertilized, and , in an attempt to see how many were viable and how many were not. Anyhow, we are supposed to do statistical analyisis and give the results, but I am unsure of what tests to run. Any direction would be appreciated! Thank you!

Is the hydrogen atom the one with the randomly disappearing proton ?

Anyone who has ever taken Micro probably had to do an unknown microbe project. Well I've ran all of my tests and, after exhausting Bergey's and Google, I still haven't been able to identify me and my partners unknown. My gut is telling me that we have Enterobacter aerogenes, but the only problem is that our phenol red fermentation test came back (-) for lactose; however, it wasn't your typical negative. It was this: I know if it isn't completely yellow then it's automatically supposed to be negative, but my tests aren't really leading me anywhere. I know if the media becomes more red or magenta then it's utilizing peptone and not the carbohydrate itself, but why …

My questions exactly are: Q 1: Why 3d10 4s1 configuration of copper is more stable than 3d9 4s2 in terms of exchange energy ? Q 2 : Can a electron of 3d exchange to 4s electron, having same spin? Q3: How many possible exchange sets with a parallel spins can occur in copper ? Please help me asap.

Thank you!

Which of these products is most effective in killing bacteria? 1. waterless hand snitizer and betadine 2. quaternary ammonia and isopropyl alchohol 3. pine sol and bleech 4. hydrogen peroxide and listerine

Of the following antibiotics, what is the best all around broad spectrum agent?What is the least effective broad spectrum agent?What was the most effective against Gram positive organisms?What was the most effective against Gram negative organisms? most resistant overall? 1.Penicilium 2.Streptomycin 3.Chloramphenicol 4.Tetracyclines 5.Bacitracin 6.Polymyxin

Sorry for creating a whole thread about this but I couldn't obtain an answer from Google. I'm revising from my textbook and I have come across the structure of 2,2,4-Trimethylpentane. I'm slightly confused as to the structure which is displayed in the book. Part of the structure is H3C but I have always seen it as CH3. Here is the structure of 2,2,4-Trimethylpentane I was familiar with -- Whereas on the structure displayed in the book, the furthest left CH3 on the trimethylpentane was displayed as C3H. Are they the same notation but displayed in different manners, a typo or am I missing something? Thanks

I need help with some study guide questions to study for the exams tomorrow. 1. What is the number of ATPs that result from one glucose in both aerobic and anaerobic conditions? 2.Which metabolic reactions of glucose take place under anaerobic conditions? 3. How many ATPs are formed from each NADH and FADH2 in the electron transport chain (ETC)? Which hormones are produced by the various cells the pancreas in response to either high or low blood glucose levels? What cells produce which hormone? (I can't find the answer for this. :/ ) Thanks! I need to do well in the exam

Please show and explain the work to figure out these questions 1. you react 3.50 g of solid sodium metal with water to produce hurdogen gas and sodium hydroxide. if at the end of the reaction there is 6.8 l of solution, what is the concentration of sodium hydroxide? Answer: 0.022 M NaOH 2. an excess of aqueous calcium chloride is reacted with 350 ml of .650 M aqueous sodium carbonate. if 10g of a solid is produced, what is the percent yield Answer: 43.8%

The question was to balance this equation What I did was Cu2+ + 2I- -> CuI + I2 But the answer is 2 Cu2+ + 4I- -> 2CuI + I2 So do 2 moles of ions of an element combine to make 1 mole of that element? Is that what I was missing?

Not technically a homework question, but I thought this would be as good a place as any to ask. I'm a science fiction writer working on a new novel that centers around a near-future manned mission to mars. I've been attempting to make it as realistic as possible, but I've hit a bit of a snag. As you know, current technology does not allow for real-time communications with a ship in orbit around Mars, according to my research at best you'd get about a 3 to 8 minute time delay. While I could work around this if I had to, I'd actually really like to have real-time communications. Now as I said, this is near-future, so I am allowed some technological leeway, but for my pu…

So a lecturer of mine posted up this question in a lecture Q11. Below is an alignment of orthologous amino acid sequences from three species (A, B and C). Species C is the known ‘outgroup’. Are the sequences evolving in a clock like fashion? A: G E N M E E V L T I N A C E B: G E N E S E V I L A S S C R C: G E N E E E V I T I N A C E and that's all very well. Except I have no idea how to do that and when he posted the answer in the next lecture, I have no idea how that answer appeared. Which I shall show below A: S E C E N D S R D H A T D E A M E L B: S E Q A N C E R F N A N D G I M E S C: A E Q E N C E S F N A N D G A S R N I would be very grateful if anyone could pro…

Hi, We have been looking at LDH isoenzymes with electrophoresis and in situ staining with a cellulose acetate strip in class and I've been a little confused... My results indicate levels as expected for the tissues, except for the kidney. The kidney seemed to be high in LDH-1 (and progressively less towards LDH-5), but it is supposed to be high in LDH-4. Is there a reason that this could be, or am I reading the results completely wrong? I hope the question made sense, I am still trying to wrap my head around this. Thank you

Hey guys So I am in 7th grade and I am doing a Science Fair project. I need to test 50 people and my results are due Tuesday. Could you guys please help? If anyone is interested please post below your e-mail. A brief explanation to my project: 1. I will send you a document with some facts (really basic stuff) that you have to read and go through while listening to a music genre. 2. 12 to 24 hours later, you will have to listen to the same music genre and answer a test, which is multiple choice and mentions the things that were on the document prior to the testing. Please don't look anything up on Google to cheat because it will just make my results inaccurate 3. After…

Problem : Replace the store Indirect (1011) instruction in the code with whatever instructions are necessary to perform the same instruction. x3000 0010 0000 0000 0010 x3001 1011 0000 0000 0010 x3002 1111 0000 0010 0101 x3003 0000 0000 0100 1000 x3004 1111 0011 1111 1111 I know I'm going to be pulling the memory from x3004 into R0 ( R0 <-- M(3003)) and then that's going to be going into M(M(3004)) <--R0 , but I tried looking at the instructions contained at that location (3004), and if it's signed, then it's a negative value? How do I find a memory location at a negative value? Can anyone tell me if I'm even thinking in the right direction?