Homework Help

When Cu2SO4·5H2O is heated, the deep blue color of the hydrate changes to a white color as the water evaporates and the hydrate becomes anhydrous. Can anyone please explain to me why this happens? Thank you! Edit: In addition, I notice that there are five molecules of water per formula unit of Copper (II) Sulfate. I know that four of them are attached to the Cu by coordinate covalent bonds, and one is bonded to the sulfate ion. In addition to that last question, how would a water molecule bond to that sulfate ion? Again, please and thank you!

HI! I don't know how to answer this question about stoichiomestry! any ideas? The potassium salt of benzoic acid, potassium benzoate, KC7H5O2, can be made by the action of potassium permanganate on toluene, C7H8. C7H8 + 2 KMnO4 --> 2MnO2 + KOH + H2O If the yield of potassium benzoate cannot be realistically be expected to be more than 71%, what is the minimum number of grams of toluene needed to achieve this yield while producing 11.5 g of potassium benzoate?

Hi, this is my first post and I would really appreciate some help I have for an astronomy homework assignment. The 1st problem involves what would be the net gravitational force exerted on a center asteroid (B) of arbitrary mass 10 placed between two other asteroids, with the left (A) asteroid having an arbirtrary mass of 5 and an arbitrary distance of 3, and the right asteroid © having an arbitrary mass of 10 and an arbitrary distance of 3. I thought that the net gravitational force on (B) would be the gravitational force between (B) and (A) combined with the gravitational force between (B) and ©, but I'm not entirely confident in that idea, and would like assurance …

Im Having diffuculty in working out the nullity of a matrix, the matrix is a=[ 1,-1,1;-1,1,-1;1,-1,1] to find the nullity i was finding the eigenvalues and than working out the nullspace and than working out its dimension, is this correct? the other problem with this is i get to the polynomial equation from det(A-Lambda.I)=0 which ends up being -x^3 + 5x^2 -5x -1 which i dont think is correct, can someone please help. also can someone explain to me what multiplicity is? Cheers

hey heres the question & heres my answer, but i got stuck so yep any help would be greatly apprectiated! ok here is what i have got so far... [math] \epsilon = 1 - \frac{Q_{out}}{Q_{in}} [/math] [math] Q_{out} \ = \ |Q_{d->a}| \ = \ C_v|T_a - T_d| \ = \ C_v(T_d - T_a) [/math] [math] Q_{in} \ = \ Q_{b->c} = C_p(T_c - T_b) [/math] so [math] \epsilon \ = \ 1 - \frac{C_v(T_d - T_a)}{C_p(T_c - T_b)} [/math] but [math] \frac{C_p}{C_y} \ = \ \gamma [/math] So [math] \epsilon = 1 - \frac{T_d - T_a}{ \gamma (T_c - T_b)} [/math] then using PV = nRT [math] \epsilon = 1 + \frac{1}{ \gamma} \frac{P_aV_a - P_d…

This is a very strange question I know, but I really dont know the answer myself- Are there any stomata on the upper epidermis of a leaf? If so, in all plants or just some? I would assume the answer is no, but my honors bio teacher likes to pull tricks

My teacher is driving me crazy he doesnt explain everything. Anyways my question is this: A helicopter travelling horizontally at 155 km/h [East] executes a gradual turn, and after 56.5s flies at 118 km/h [south]. What is the helicopter's average acceleration in kilometres per hour per second. I dont get how we are supposed to do this without angles. how am i supposed to find the components of x and y. Can anyone please help me??

Hey, can u guys help me answer a few of these questions? A. How fibre optics are capable of transferring information in the form of laser light pulses B. How laser light pulses are then converted to digital signals for audio, video or computer data C. The advantages of this form of long distance information transfer. Can you also give me a few websites that I can look through myself? Thanks.

My book stinks it doesnt explain or show you how to do enough examples. But anyways i have another problem now. I figured out how to do my other question. Anyways my question is....... A car with a velocity of 25 m/s [E] changes its velocity to 25 m/s in 15s. Calculate the car's average acceleration. How do i start this question off. I dont know what to do.

Sorry is its really hard to read the chart but i dont know how to fix it. Anyways there are 4 different lengths and at each length the resistance gets stronger and stronger. i guess i'll write a little about the chart. The first column is Diameter the numbers are 0.025, 0.04, 0.075, 0.125. The next columns are resistance differing between length. The first column of length is 100 and the resistances are 15.7, 6.1, 1.9 and 0.6. The next length is 140 and the resistances are 22, 8.5, 2.5, 0.9. The next length is 170, the resistances are 26.8, 10.4, 3, 1.1. The final column of length is 220 and the resistances are 34.7, 13.3, 3.9, 1.4. I hope that helps. Anyways my question …

I dont not understand velocity and speed in two dimensions. My teacher barely explained it and i do not know what to do except for the part of finding out the coordinates. Anyways heres a question i hope you will be able to help me with. Determine the vector sum of the displacements d1= 2.4 m [32 degrees S of W]; d2=1.6 m ; and d3= 4.9 m [27 degrees S of E]. do i add one and subract the rest i dont get it. This is what i did so far, is this right? drx= d1+d1+d3 =2.4cos32 - 1.6 - 4.9cos63 =2.08 - 1.6 - 2.22 = -1.79 dry= d1 + d2 + d3 =2.4sin32 - 1.6 - 4.9sin63 =1.27 - 1.6 - 4.365 = -4.695 I dont know whether i was supposed to add these or subtract…

Let [math]f(x) = (1 + \frac{1}{x})^{x}[/math] a. Find the domain of f. b. Draw the graph of f. c. Explain why x=-1 and x=0 are points of discontinuity of f. d. Are either of the discontinuities in part c removable? Explain. e. Use graphs and tables to estimate [math]\lim_{x\to\infty} f(x)[/math] I don't really know how to do a. There are a lot of values between -1 and 0 that are undefined. B and C are easy enough. D I have trouble because I don't know how to find the limit with the exponent. Would substitution be valid? And e I can handle. Thank you!

Hey, I have a question... okay first I had to find a real world application to this point: perform a first-hand investigation, analyse information and use available evidence to model the differences in atomic arrangement of diamond, graphite and fullerenes Well, the hardness of diamond (physical properties) is related to its molecular model... Now, the question asks me to draw a graph and an equation; do you guys know of anyway to integrate the physical properties of a mineral for example diamond into an equation and graph... for example, what equation can we include using diamond? What's the original reaction that takes place in order to create dia…

Anyone know of any properties of simple carbon compounds, (eg. methane, butane, propane, etc.) that when graphed will give varied results. You see, i need to create a graph with a curve of best fit so i need properties which prodice scattering results Thanks

Ok. So I don't get them at all. I have a MAJOR test on Monday, not to mention some homework grades. I have been able to do some of the problems, but the following are stumping me. If anyone knows the answers that would be great. What would be better is if you could tell me how to do it. Thanks! 3) The length of the barrel of a primitive blowgun is 1.2 m. Upon leaving the barrel, a dart has a speed of 11 m/s. Assuming that the dart is uniformly accelerated, how long does it take for the dart to travel the length of the barrel? 4) (a) What is the magnitude of the average acceleration of a skier who, starting from rest, reaches a speed of 6.8 m/s when going down a…

I've been having some problems with these, if someone could help that's be nice. Perform the indicated operations and simplify. x^2 - x - 6 x^2 - 3x - 4 x^2 + 4x + 3 * x^2 - 4x + 3 (Note: This was originally a division problem but I flipped the last fraction to make it multiplication as I think your suppose to, that and I didn't know how to type the division sign.) Find the lowest common denominator: 5a - 15, 10a - 30 Solve the equation. 2 + x - 1 = x^2 - 1 x + 2 x + 3 x^2 + 5x + 6 Perform the indicated operations and simplify.

According to my teacher, I have about 21 days to type up a 6+ page paper on a social problem. To tell you the truth, I don't give a **** about society a good amount of the time. However, in this case I have to type up a paper with sources on a social problem. I don't want to spend forever on the paper because I have about 20 days and about 4 hours a day to spend on it, giving me 80 hours. So what do you think would be a good social problem to write about? I could simply go for the obvious which is marriage, divorce, suicide, pregnancy, government.. But some of those are too broad. Even more education since I'm not in public schools anymore. I f…

I did a lab recently where I had to measure length, width and height of different sizes of beach wood with a ruler (so gave each measurement 2 decimals). I also measured each piece on an electronic balance (the reading gave 2 decimals). I calculated the volume of each block and graphed against the mass. Could you plz. tell me as many sources of absolute uncertainties affecting my observations for each measurements and a brief explanation for each so I understand. I have this so far: parallax, edges of block not smooth. Could someone plz. explain parallax to me and how it affects my lab. Thanks in advance.

OK, here's the question: Neutrons were discovered in 1932, more than 10 years after the existence of isotopes was confirmed. What property of electrons and protons led to their discovery? I don't know the answer at all! Please help!

hey guys, i need some help for this chemistry question i have a topic which is:"the importance of the heat capacity of water to aquatic life" i have found information and diagrams but i need a GRAPH, this graph must somehow relate to my topic, thus it must have something to do with aquatic life. if any of you guys could find some data in a table, i would be very thankfull thus i could use the table to make a graph. thnaks again!

Question: How much of each compound is needed to make 0.5 g of 80%/20% (mole %) mixture of cinnamic acid and urea acid? So far, I have the molar mass of individual compound: cinnamic acid =148.16 g urea = 60.062 g i tried to do 80% of 0.5 g which gave 0.4 g of cinnamic acid, but i am sure that is wrong because the % is not mass/weight % but rather MOLE%, which i do not know how to do. please help?

Could we build one today in the same time limit they had? >< Probably sounds stupid but I want another opinion ^^" With todays technology and the time limit of one Pharaoh's lifetime. And without todays technology ^^" if that's not too much.

im currently researching the combustion rates for various fuels. Do u know of any good sites which will help me in my research? i also need a graph for these results, theres no specific data that im looking for, just any graph relating to combustion of hydrocarbons will do thanks in advance

If anyone could help me out I would appreciate it very much. My question asks to calculate the theoretical mole ratios versus the observed mole ratios (got that part recorded) of sodium hypochlorite and sodium thiosulfate... now here's my problem: I can't figure out how to balance NaHClO and Na2S2O3. I can't really figure out where to begin and I don't know what the products would be. thanks for any help edit: and it asks for the net ionic equation for the reaction and calculate the enthalpy change (I think I just drop the Na in the equation but I'm not sure) oh yeah and the mixture was 0.5M Sodium Hypochlorite solution and 0.5Msodium Thiosulfate solution

The experiment is a basic kind of precipitation reaction, you have 2 solutions in two bottles and you add to drops of each solution onto a sheet of transparency and see if precipitate forms. Well, one particular reaction that has me wondering was the .1M NaOH. First we mixed it with 2 strong acids and of course no reaction. 2 transition metals gave 2 precipitate. BUT, in group II the alkaline metals, we mixed .5 M Mg(NO3)2 with .1 M NaOH and no reaction occurred. However, when we mixed the same NaOH of same molarity with .1 M Ca(NO3)2 one guy in my group deciding that it was a precipitate present. Does Calcium Hydroxide produce a precipitate? Does Mg(NO3)2 form a precipit…