Homework Help

Consider the following reaction: 4NH3 (g) +7O2 (g) <-->2N2O4 (g) + 6H2O (g) If the initial concentrations of N2O4 and H2O are 3.60 M. At equilibrium the concentration of H2O is 0.60 M. Calculate the equilibrium concentration of N2O4. Can someone tell me how to solve this, i am lost, thanks!

Hey, does anyone have IBSL Physics May 2004 paper? I have an exam coming up this thursday and desperately need help.. If anyone has it, please send it to woohyunjin@gmail.com (I would greatly appreciate it if you could also attach the markschemes). Oh by the way, if you are in need of any past papers for IB, I have quite a load so contact me. Thanks

hey guys, i was wondering who is good at science? The reason i am asking is because i got some 6 six questions from TAFE, and i don't have a clue how to do them? So here they are: 1. Use the equation of motion to calculate the speed and distance travelled by an object falling from rest under gravity after 3,6 and 9 seconds. Take g=10 meters per seconds squared. 2. A force of 20 N acts for 8 seconds on a mass of 60Kg. What is the (a) acceleration, (b) final speed, © average speed, (d) distance covered during the 8 seconds. 3. A force of 20 N is exerted on the handle of a door 0.6 meters from the hinge. If the force acts a right angles to the door, what is the m…

67877 L of concentrated nitric acid (74% by mass, density 1.46 g/cm3) was split on a road. Sodium carbonate was spread on the acid to react as in the equation: (CO3)2(aq) + 2H ------> CO2(g) + H2O. How many grams of sodium carbonate are needed? If you answer is in the form 5.00 x 102 write in 5.00e2

The road wheels of a car exert a tractive effort of 1000N when travelling at 50KM/h. Calculate the work done per minute?express in Joules What power is the power developed by the car at this speed? express your answer in kilowatts. Can anybody help with how to work this out? cheers

hi, ive been asked to plan an investigation to find out if there is a relationship between the concentration of phosphate ions in nutrient solutions and the number of cells dividing by mitosis in root tips (i'm assuming on using hydroponics obviously) but im really stuck! can any of you lovely people help me out, either with the scientific knowledge or actual investigation? Thanks, Angel (that is my real name please dont laugh at it!)

THe questions states: Using the locus appraoch(definition) of the hyperbola to write the equation of the hyperbola with centre (o,0) foci (17,0) (-17,0) and difference of the focal radii 30. How do i solve this?

hey guys, can u help me with these 3 questions? 1. Naphthalene combustion can be used to calibrate the heat capacity of a bomb calorimeter. The heat of combustion of naphthalene (C10H8) is 40.1kJ/g. When 0.8210g of naphthalene was combusted in a calorimeter containing 1000g water, a temperature rise of 4.21 degrees C was observed. What is the heat capacity of the bomb calorimeter excluding the water? (What i've got so far is that since heat of combustion is 40.1 kJ/g, so 401 x 0.8210 = 329.221kJ must have been released by naphthalene. Next i think i should use q = ms(delta T) except i'm not sure how we're meant to find the heat capacity of the bomb calorimeter "e…

can i have some confirming plz? 1. The vapour pressure of pure water at 25 degrees c is 23.8 mmHg. Determine the vapour pressure of water at 25 degrees C above a solution containing 33.2 g of urea (a nonvolatile, nonelectrolyte, MW = 60g/mol) dissolved in 75 g of water. (i found no. of moles of urea = 0.5533 and no. of moles of water = 4.1667. since P(solution) = x(solvent) x Pure pressure (solvent), P(solution) = 21.01 mmHg.) does anyone agree with my answer?) 2. Calculate the reaction enthalpy in kJ for the formation of anhydrous aluminium chloride 2Al(s) + 3Cl2(g) --> 2AlCl3(s) from the data: 2Al(s) + 6HCl(aq) --> AlCl3(aq) + 3H2(g) delta H…

Well to begin . I'm crap at maths and I have a test after the weekend is over , I didn't turn up to maths class the other day and now I missed out and forgot what I'm supposed to know about in/equations . darn . If anyone can spare a little time explaining to me how I'm suppose to approach : Simultaneous Solutions Gradients intercepts With an example to use : inequation : 3x-5y<15 and equation : 2t-4c=11 It would very nice of you .. thanks heaps in advance

Oh boy here we go....writing straight line equations from y=mx+b to standard form (Ax+By+C=0) y=mx+b i know that y=-1/2 m=1 and x=4 .:. -1/2=(1)(4)+b -1/2=4+b find common demoninator and multiply it by all 2(-1/2) = 2(4)+2(b) -1=8+2b isolate b -2b=8+1 -2b=9 b= -9/2 as a rule though....no fractions in final answer get everything on one side 0=x-y-9/2 common demoninator, multiply it by all 2(0)=2x-2y-2(9/2) 0=2x-2y-9 just switch so =0 is on right side....neater 2x-2y-9=0 Eh? Did I do it right...I think I did....this is how we were taught...sorry it's long I know....

Dialysis tubing is a transparent, selectively permeable layer. It is artificial. If we pour some sucrose solution into it, the sucrose molecules cannot escape as they are too big to do so. What happens if we boil the dialysis tubing? I think sucrose cannot pass through the layer either since the layer does not consist of living tissues/cells which contains living cell membrane destroyed the heating. Am I correct?

please couldsomone help me on my problems in the math forum. noone has actaully helped me, and help i need. so please check out my thread in math, thank you those who respond.

Hi! I am an 8th grade honors science student. I have to do a project in which I create an animal capable of living on another planet. lucky me, i got venus (220mph winds, 800degrees f, sulfuric acid clouds, who wouldn't want to live there? ) We have to find a way for it to eat, breath, and deal with the surroundings. I was planning on having it eat the microbes they believe may live in the atmosphere. if anyone has any suggestions, in plain english when possible, i would appreciate it. thank you!

Hey, if anyone reads this within the next hour could you please help What class of organic compound is hydrolised in aqueous acid to produce a carboxylic acid and an amine? a acetal b ester c imine d anhydride e amide i thought it might be b but im still unsure please help t

hey guys, can u help me with these few questions? 1. In the molecule below, which carbon atom is in the highest oxidation state? BrCH2CH(OH)CH(OH)C(=O)CH2C(=O)OCH3 (I have NO idea of what to do!!! Can any1 help me?) 2. In the reduction of carbonyl compounds with LiALH4, the effective reducing species is: (a) Li+ (b) Al(3+) © AlH4(-) (d) AlH3 (e) H- (i think the answer is c...any1 agree?) 3. What is the IUPAC name for the following compound? CH3CH2CH2CH(Cl)C(=O)Cl (a) 1-chloropentanoyl chloride (b) 1-chloro-1-butanoyl chloride © 2-chloropentanoyl chloride (d) 1,2-dichloropentanal (i think the answer is c...wat do u guys think?)

hey can anyone confirm whether i've got the name of this organic compound right? CH3CH(Br)CH(CH3)CH2CH(phenyl)CH2CH3 is it 2-bromo-3-methyl-5-phenylheptane? (or is it 6-bromo-5-methyl-3-phenylheptane?)

hey guys can u help me/confirm these 2 questions? i've attached them (their just pictures of the questions that i took with a digital camera - coz im not sure how to just put an image in *blush)..hopefully the attachments worked

Hey. I just need some help on coming up with an original idea for a science fair project. I don't know where to begin. I need a topic asap. I would really appreciate the help.

60 L of a gas were collected over water when the barometer read 670mmHg, and the temp. was 20C. The pressure of H2O vapor at 20C is 17.5 mmHg. What volume would the dry gas occupy at standard conditions? I used the rearranged equation: V2=T2xP1xV1/t1xP2 and got 2329.5 L. Is that correct??Any help would be appreciated. Also, what gas equation is to be used to answer this problem: N2 occupies a volume of 600mL at 60C and 650mmHg of pressure. What will the volume be at STP??

1. How am i supposed to found out how much of a certain molecule is needed to neutralize another molecule? ie. "How many milliliters of .400 M KOH will neutralize 25 mL of .600 M H2S04?" 2. How do i find out the molarity and concentration of a molecule in a solution? 3. What salt is produced from the reaction of H2SO4 and KOH? ("is it K2SO4?") Thanks for your replies. If you are going to reply...

I have a question about truth tables for the logic gates. I am given the truth table, I have to work out what the circuit would look like and what the function of the logic gate is ... like I have to find out : x = a.b.c + a.b + c that was just an example.. Now this is the truth table i am given: A B C Output 0 0 0 0 0 0 1 1 0 1 0 1 1 0 0 1 0 1 1 0 1 0 1 0 1 1 0 0 1 1 1 0 Would anyone be able to tell me the function of this truth table, or tell me the diagram of the setup of the combined logic gates, i think it SHOULD be used with AND OR and NOT gates combined.

I need an idea for an earth science research project idea by the end of this week, that can be done within 3 weeks. Requirements -Must be a research topic -Must be at High School level (grade 10 and up) Thanks for the help. -Hoffman

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I have to do a small speech on racism on Wednesday. The topic is: "To what extent do you think racism still exists in America today? How has racism changed over the years. Stat examples and possible causes of racism today." I haven't been able to find any information on the subject. I've tried Google but there wasn't anything useful. I need some information or a link to some soon. Thanks in advance. I'm going to go try a different search engine now...