Homework Help

The impact of science and how the scientific methods used in physical sciences and natural sciences as a whole. My professor is not very well fluent in English. All I need is a good interpretation of what this means. I have to write an 8 to 10 page report on this. Whatever the best interpretation is I will go with.

When is it correct to draw a lone pair of electrons on a carbon atom in a molecule when drawing resonance structures? Is it correct as long as the carbon atom fits the X=Y-Z* model? The "X" atom and "Y" atom are double bonded and the * denotes the "Z" atom, which is single bonded to the "Y" atom, has either an empty orbital, orbital with one electron, or a lone pair. In carbon's case I believe it would usually be an empty orbital.

I'm re-reading my organic chemistry book to prepare for a lab class, and I've taken a quantum chemistry class. I don't remember too much from quantum chemistry. In a general chemistry sense, is there a way to determine a number of bonds an atom can make just by looking at its position from the periodic table? For example, without quantum chemistry knowledge, how should I know that phosphorous can make 5 bonds? Is it just something to be memorized until quantum chemistry?

Hi all, I'm a high school student looking to perform research for science fair, but I want to make sure my experiment follows the "Use of Humans as Test Subjects" rules. 1. Part of my experiment requires participants to undergo ~24 hours of sleep loss. I understand that sleep loss is taxing on the body, but the negative effects of pulling an all-nighter do not pose any serious health risks and disappear after a good night's sleep. Would this violate the rule "Humans must not be subjected to treatments that are considered hazardous and that could result in undue stress, injury, or death to the subject"? 2. My experiment also requires the administration of caffeine…

I have been asked to write a conclusion about the effectiveness of writing programs in block programming environments compared with high level programming language such as Java, Python or C++. Could someone help by maybe listing the advantages and disadvantages of both and anything else that could help me answer? thanks!

ok i need some help i been doing one of my last cores for my grade 12 online and i been running in to some problem most of the time i can think my way out of it but some time i would like a little help. now you would say well go ask the teacher and i have the problem is he never gets back to me he allways just marks my stuff and i get full marks idk if im doing stuff right or if the way i figured it out works all the time because he never msg is me back i even emailed him and nothing soo i turn to you guys the science forums for help. soo i was wondering if you could tell me if i was doing a few of theys questions right and if i need to be doing something different first…

I have 2 questions and I would be most grateful if they could be answered. 1. When default names are assigned to components in a program, why does the programmer change the default name? 2. How is block programming environments (software's such as Scratch, BYOB, App inventor where the programmer uses blocks which attach together like jigsaw pieces to create programs) effective compared to high level programming languages (programs written out by the programmer in software's such as Java Script, C++, Small Basic)? Thank you for your help

Hi everyone Another one for tomorrow: [math]I=\int{x\cdot\arcsin{x}\text{ d}x}[/math] [math]I=\int{\arcsin{x}\text{ d}\left(\frac{x^2}{2}\right)}[/math] [math]I=\frac{1}{2}\left(x^2\cdot\arcsin{x}-\int{x^2\text{ d}(\arcsin{x})}\right)[/math] [math]I=\frac{1}{2}(a(x)- b(x))[/math] [math]b(x)=\int{\frac{x^2}{\sqrt{1-x^2}}\text{ d}x}[/math] Let [math]\sqrt{1-x^2}=u[/math] [math]\text{d}u=\frac{-x\text{ d}x}{\sqrt{1-x^2}}[/math] [math]\text{d}x=\frac{-\sqrt{1-x^2}\text{ d}u}{x}[/math] [math]b(x)=\int{\frac{x^2\sqrt{1-x^2}\text{ d}u}{-x\sqrt{1-x^2}}}[/math] [math]b(x)=-\int{x\text{ d}u}[/math] [math]u=\sqrt{1-x^2}\Leftrightarrow…

Q2. Pinch technology tutorial 1 A Network of heat exchangers is described below in data table 1. A) Produce a table showing the energy available from or required by each stream. [5 marks] B) Construct the incremental temperature–enthalpy table for the hot and cold streams. [10 marks] C) For a minimum temperature difference of 10 ˚C and the data given below construct the composite temperature enthalpy curves. [10 marks] D) Construct the shifted temperature curves. [5 marks] E) Construct the grand composite enthalpy curve and identify the pinch temperature. [5 marks] F) Determine the minimum utility heat input and the minimum heat lo…

Town Q is 20km due north of P. The bearing of town R from Q is [latex]140^0[/latex]. If R is 8 km from Q. calculate: (a) the bearing of R from P, to the nearest degree: (b) how far north of P, R is, correct to 2 significant figures; Drawing the diagram is my main problem. If you can help me with the drawing, I can attempt the working.

Hi guys, I'm having some trouble with a couple of questions. I've attached the image for you to see. The membrane is only permeable to glucose and water, and the surrounding fluid is hypotonic in terms of glucose, so you would expect the cell to swell (right?). However, if it diffuses into the cell, the glucose % inside the cell will rise... so how could it reach equilibrium by doing this? The only 2 options for reaching equilibrium I can think of are i.) Glucose moves out of the cell - however (as far as I understand) it isn't able to do this due to being submerged in a hypotonic solution, or ii.) Water moves into the cell - however this isn't an available option (an…

This is an extra credit assignment for my Intro to Computer Science class, it's the only Computer Science class I've taken so far. I do not even understand what this assignment is asking me to do. My professor is terrible at answering questions. What kind of format am I even supposed to answer this in? I'm not looking for the answers I just don't even understand where to start or what it's asking of me. Any help would be monumentally appreciated. "This assignment can be done in any way that is most comfortable for you. At the beginning of your program, be sure to provide comments that give your name, the nature of the assignment, the name of you program, and due da…

I suck at this.I try to do some exercises maybe i will get something but i can't really do anything...I've done some parts of the exercises but i can't do some of them.Can somebody explain me how I must do them and why it's like that? 1.We have an object m=1kg).It's on the ground but it's going up(vertically) with a speed of 10m/s. The air friction doesn't matter and the gravitational potential energy is considered 0 at the ground level. The question is : what's the speed of the object when potential energy is the same with the kinetic energy? 2.Look at this..."picture".I translate the data here: http://i.imgur.com/wfZJmlQ.jpg m=5kg v0=10m/s B=30 de…

Hi, I am having trouble understanding this question. The answer in the back of the worksheet is (A). I understand that the ΔG = 0 but why is pressure > pt? Consider a pressure – temperature phase diagram with the triple point at a pressure of pt and a temperature of Tt. If a system is on the phase boundary between solid and liquid phases, which of the following statements is always true for the system? (A) ΔG = 0, pressure > pt (B) ΔG ≠ 0, temperature > Tt © ΔG = 0, pressure < pt (D) ΔG = 0, temperature < Tt (E) ΔG ≠ 0, pressure > pt Thank you

Ok so I have a bunch of questions that I need help with so I am just going to make one big post, all the help I can get is appreciated!!! 1) A cylinder contains 3.0 kg of a water mixture that is in two phase equilibrium at a pressure of 500 kN/m2. If the volume of the cylinder is 1.0 m3, determine the following: a) Temperature of the mixture in the initial equiulibrium. b) Volume and mass of liquid water. c) Volume and mass of vapor 2) A cylinder has a volume of 0.2 m3 of O2 at 70 C and 25.0 bars. Calculate the…

Hi there, I was wondering whether anybody would be able to help me with a question on NMR. "The Lac repressor is a 150,000 MW tetrameric protein consisting of a core and a DNA-binding headpiece. Comment on the information that can be gained from the 1H NMR spectra below." The isolated headpiece I suppose becomes unfolded in the absence of the core, giving greater flexibility and thus the broader peaks. However, I am stumped by the isolated core! At first glance, I would suggest that the core is small with few nuclei and thus a low intensity. However, looking up the structure I can see that the core is actually larger, so I'm not sure how to interpret it! Coul…

Hi I asked the question below on another website and was told that the answer is 66.66666667ml not 600ml. Any chance of a second opinion? The answer in my worksheet states it's 600mL I was just wondering if someone can check over my working for this problem and let me know if I went wrong anywhere or any useful tips that they wish to share? (Everything that I wrote is in the *** triple stars ***) Dichromate ions, Cr2O72- reacts with iodide ions I^‐,in acidic aqueous solution to form Cr3+ ions, iodine molecules I2 and water, according to the following unbalanced equation: Cr2O72- + H+ + I- → Cr3+ + H2O + I2 ***Cr2O72- + 14H+ + 2I- → 2Cr3+ + 7H2O + I2*** …

I would just like to know what equations I would need to answer a question like this. I am sure once I have the equation the math will be very simple. Any help or advice would be greatly appreciated. "When using a recirculating packed column scrubber that is 100% efficient how much sodium hydroxide at 20% would be used per hour if the flow rate of 300,000 ppm SO2 was 15 cfm? How many hours could we run the scrubber until the caustic had neutralized all of the SO2?" I assume 100% efficient means the outlet gas stream has a SO2 concentration of 0% but I could be wrong. Can anyone give me any help setting up the equations for these two problems?

Hello need some help with this journal : http://www.impactaging.com/papers/v6/n2/full/100636.html 1. How long did the study take to complete and was it repeated (or only done once). 2. Why was study done, and please explain the conclusion

This is my first gram stain I am in the process of writing up what I have found but I can see purple and red on the same species. This was taken from a yogurt and should be gram +ve. Is there too much on there or culture too old and its variable? Sorry its not a good quality picture and any help is appreciated. Alevel student I have attached a pic please advise me if you can't see it.

Hi all! I may not have the necessary knowledge in chemistry to calculate such seemingly easy problem. How much pressure is needed to compact 30kg/m3 density PS into a 330kg/m3 one? Can someone please explain me this through equations? Hope I am not to be expelled for my noobness

I have to use drawing and coloring methods in Java in a Java Applet to draw an image that looks almost exactly the same as this one:http://img3.wikia.nocookie.net/__cb20090802231620/sonic/images/a/a1/Shadow_26.png . My teacher will look at the code I used to draw the image. I'm trying as hard as I can but there's 'stuff' going on at home and I'm taking advanced classes. I'm trying to manage all the stuff, but it's getting hard. Can someone tell me a shortcut or help me out?

When Phosphorus (P) is bonded to three elements, and double bonded to one, how is P sp^3 hybridized? sp^3 hybridization only offers 4 orbitals, yet there are 5 bonds. McMurry's Organic Chemistry textbook says the bond angles are similar to a tetrahedral configuration, and that is why P is sp^3 hybridized in that situation. I understand P is capable of forming a different number of bonds depending on what molecule it is a part of. How can I determine the hybridization of P in a molecule?

Hi, How did they get equation 15.5.7?

Zinc's ground state electron configuration, with all numbers in parenthesis as exponents, is 1s(2)2s(2)2p(6)3s(2)3p(6)4s(2)3d(10). This question confuses me because 4 is a bigger number than 3, however part of the third shell is higher in energy than part of the fourth shell. Is the valence shell the third or fourth shell? If the third shell is the valence shell, are all the third shell electrons considered valence or only the 10 in the d orbitals? To gain the nearest noble gas configuration will Zinc gain 6 electrons in the fourth shell p orbitals, or will it lose the 2 electrons in the fourth shell s orbital? Thanks in advance.