Chem

7,331 results
  1. chem- drbob222 please help

    my original question was: how do i figure this out?? How much heat does your body lose when 2.46 g of sweat evaporates from your skin at 25°C? chem - DrBob222, Tuesday, February 22, 2011 at 10:52pm q = mass water x delta Hvaporization. chem - Rebekah,
  2. chemistry

    can you please give me some practical applications of qualitative chem and quantitative chem...
  3. chem

    so i posted this question yesturday and got some help. which is the stuff below. can you look at the last thing i said which was the answer i got by doing what DrBob222 said to do and tell me if its correct.(the question is the first section) thanks chem -
  4. chem

    what are the other practical applications of Analytcal chem on being a medical technologist?
  5. Advice...about chemistry degree Dr.Bob

    Based on the question topic posted by Britney below titled:In your opinion (your answer to this reminded me of something) (I posted the same thing there but I thought it was improper to piggyback on that post so I posted this under a new topic) I don't
  6. Chem- bobpursley

    What mass of protons would be required to just neutralize the charge of 1.5 g of electrons? my teacher said .0015kg times 1e-/.00091e-27kg times 1pt/1e- times 1.67262e-27 over 1 p chem - bobpursley, Tuesday, September 21, 2010 at 6:48pm That is what I
  7. Gen Chem II

    Thanks for the information Dr. Bob. Would you be able to work it out so that I can actually see the steps with the numbers and follow from there. The question was on Vitamin K from Sunday at 2:44pm which you answered at 3:45pm. Thanks again. I am looking
  8. chem - br bob is this right

    What is the pH of a solution prepared by adding 4.000 grams of NaOH to a 50.00 mL of a buffer that is 2.00 molar both in acetic acid and sodium acetate? (Assume final volume is still 50.00 mL) * chem - DrBob222, Wednesday, April 21, 2010 at 10:52pm * chem
  9. Dr.Bob222 Chem

    I believe that you are correct because you have more experience in G-chem then I have. But how does doubling the reaction rate double the k value? Isn't k just a constant for a particular reaction?
  10. chem

    if a car produces 81g of {\rm CO_2}, how many grams of {\rm O_2} are used up in the reaction? the complete chem reaction is C2H6O+3O2--->2CO2+3H2O
  11. chem chem

    hi does anyone know what the VSPER theory is
  12. chem

    What is another name for cardamist? Please write the formula and a link to its structure. See http://antoine.frostburg.edu/chem/senese/101/consumer/faq/what-is-cardamist.shtml
  13. AP CHEM

    A secondary alcohol results from the attachment of a hydroxy group to which carbon atom? C | <---GIVEN STRUCTURE C1-C2-C3-C4 A) C1 B) C2 C)C3 D)C4 Answer is C! I have to explain why, but the teacher never taught us anything about organic chem. So please
  14. Chem Help!

    I really need help with this question for my chem H.W. 1) On a summer day in Breckenridge, Colorado, the atmospheric pressure is 525 mm Hg. What is this air pressure in atmospheres? (round to the hundredths place) atm
  15. Chem 1

    Write a chemical equation that shows how acid rain H2SO3 was produced from SO2 gas and water in a zip sealed bag? My chem. teacher never explained how to do this and I have several other questions on this type of subject. If you could help me out it would
  16. Chem - DrBob222 & drwls

    Just want to say thanks to you guys for the help you gave me during the last couple of months. It was all in preparation for the National Chemistry Test and I just received word I have been selected to be in the running for the National Chem Team. Thanks
  17. CHEM (DrBob222)

    I had posted the question to that previous chem question, regarding Mo & V...they said that it should have been correct. What I am thinking that I was missing...must have been that I did not include 4s & then just not fill it. I had excluded it from my
  18. Chem

    What causes dispersion forces? Disperson forces are caused by an unsymettrical distribution of charge in the molecule, causing a net electric force. http://www.chem.purdue.edu/gchelp/liquids/disperse.html
  19. chem equations

    could someone tell me how i could solve this chem equation CH4 + NH3 +O2...> HCN +H20 AND USE THE LOWEST WHOLE NUMBER COEFFICIENT i WOULD BE GRATEFUL FOR ANY POINTERS Try these coefficients. 2,2,3==>2,6 Hi bex heres a little more help for you. Answer
  20. Chemistry

    Ok, so in my gen chem 1 class, the teacher showed us that ethanol would not dissolve a sugar cube while water dissolves a sugar cube easily. No explanation was given, she just told us we would find out in gen chem 2. Here i am in gen chem 2, and the same
  21. I have a question concerning Spring Semester

    Im a freshman in college and I just took Chem1, Trig, and Drama (12units). I am planning on taking Chem2, Pre-Calc, and Art1 for spring sem. (13units). I'm not sure if this is too much to take for next semester considering two five unit classes or should I
  22. Gen Chem

    For my chem class I have 3 elements and have to find what they are used for today or an interesting fact. I have looked but I can't really fin anything. My elements are: Cobalt,Thulium, and Roentgenium I found that cobalt is used in money (nickels,
  23. organic chemistry

    whats the difference between inorganic chem and organic chem? im really confuse because mrs. white told us inoraganic is about ionic bonds while organic is about covalent bond. what is the difference between the twooo? please help me
  24. chem org

    dipole-dipole means? and diff between non polar and polar? is it really part of organic chem?
  25. Chem

    Calculate the expected volume of hot water that would be required to dissolve 0.15g of benzoic acid, vanillin, phthalic acid, salicyclic acid? You don't need to do all or any of them. I just need to know what formula to use and what to sub in and I can do
  26. CHEM organic chem

    i am really confused! i am doing the production of ethene from fractional distillation and i understand the whole concept of it what i don't get is how i can write a balanced eqn to show how ethene can be produced from C14H30 (tetradecane?!) i did C14H30
  27. CHEM organic chem

    i am really confused! i am doing the production of ethene from fractional distillation and i understand the whole concept of it what i don't get is how i can write a balanced eqn to show how ethene can be produced from C14H30 (tetradecane?!) i did C14H30
  28. chem help

    im doing a graph for chem lab with excel. my classmate created a graph with these coordinates: X: 3.50 X10^-3 3.14X10^-3 3.28X10^-3 Y: -11.7 -8.96 -9.75 They got R2=0.998 but i got y = -3074.9x R² = 0.6291 why is it wrong. im desperate please help! screen
  29. Final-Chemistry

    I have finals coming up in a week and a half. I know I should have started studying earlier, but I just had an exam in my chem class and was focused on getting the information for that exam mastered before I started studying for the final. Now, I'm
  30. AP Exams?

    I am in AP Chemistry and AP U.S Hisotry and I have planned on taking the tests. So far I have made an A+ in APUSH, but I an B in AP Chem. I've done kinda bad on the tests I've taken in there and I don't think I will do good on the Ap exam. I think I have a
  31. physics vs. Chem

    Doesnt physics seem to be harder than chem? Anyone?
  32. Math

    in a class of 60 students 30 like maths 25 like physics 30 like chemistry. if 10 like both physics and maths 5 like maths and chem and 5 like phy & chem and 3 like all the subjects. find student like none of subject if 100 students were surveyed
  33. Math

    in a class of 60 students 30 like maths 25 like physics 30 like chemistry. if 10 like both physics and maths 5 like maths and chem and 5 like phy & chem and 3 like all the subjects. find student like none of subject of if 100 students were surveyed
  34. sand bath (chem)

    what are disadvantages and advantages of using a sand bath to heat something in chem?
  35. General Chem

    So for Chem we have to answer a question asking why graphing is a more accurate method for measuring density than manually calculating the density. I originally thought that manually calculating was better, but my teacher told me that I would have to back
  36. chem -repost for bobpursley

    i don't know how to solve this. looked through all my notes but i'm not sure what kind of formula i am to use or if i even need one! please help me to understand the theory behind this: "calculate the work need to make room for the products in the
  37. Chem

    A 10.0% by mass H2SO4(aq) solution has a density of 1.07 g·cm-3. How many milliliters of solution contain 8.34 g of H2SO4? What mass (in grams) of H2SO4 is in 248 mL of solution? It's been a while since I have had a chem class...so sorry if this seems
  38. chem/science

    Please predict what will happen. Im not very good in chem. Iron metal and pb(NO3) Lead metal and Mg(9NO3)2 Copper metal and AL(NO3)3 Lead metal and AgNO3
  39. chem HELP PLEASE its physics side of chem

    given E, = l^2 h^2 / 2 m r^2 calculate energies for an electron localised to a circle of radius 2 x 10^-9 m for l = 0,1,2, draw pictures of three levels and calculate the relative populations of these levels at 300K i did the first bit but came out with,
  40. Lab in general

    I just read my syllabus for lab and I am kind of shocked at what it says. I do know that I have to write out procedures of the lab in my nbk before coming to lab but I just read that it says "You will NOT be allowed to refer to you textbook/handout during
  41. Chem

    Are: Ba(NO3)2, Ti)2, MgI2, and Ca(CH3COO)2 soluble or insoluble in H2O @ 25degrees C? Here is a site that lists the solubility rules. You should know this table; eventually you will want to know it so well that it is memorized. If you still have questions
  42. CHEM 2: Boiling Point

    Which Aqueous solution has the highest normal boiling point? a.) 0.1 m NaCl b.) 0.1 m C2H5OH c.) 0.1 m CaCl2 d.) They all have the same boiling point. I think that the answer is D, the all have the same boiling point. Is this correct? Because Delta T=
  43. drying agent in chem

    Is it advisable or not to leave a solution in drying agent for a few days? ~I did this ..since my chem lab instructor said to but I'm not sure I believe him. He sounded unsure of himself when he answered me. solution: methylene chloride (extracting oil of
  44. High school AP chem

    The solubility of Mn(OH)2 is 3.04 x 10^-4 gram per 100 ml of solution . A) write the balanced chem equation for Mn(OH)2 in aqueous solution B) calculate the molar solubility of Mn(OH)2 at 25 degrees celcius C) calculate the value of the solubility product
  45. Chem

    The solubility of Mn(OH)2 is 3.04 x 10^-4 gram per 100 ml of solution . A) write the balanced chem equation for Mn(OH)2 in aqueous solution B) calculate the molar solubility of Mn(OH)2 at 25 degrees celcius C) calculate the value of the solubility product
  46. chem-> front page report

    wondering if this looks good or should I make the format some other way. Multistep Synthesis of 4-Bromo-2-Chloro-6-Iodoaniline name school Chem###sec## Multistep A,B March 13,2008 Multistep C March 20,2008 Multistep D March 27, 2008 Multistep E April 03,
  47. science(chem)

    Concerning TLC plates... 1. why should't I allow the solvent to reach the top of the plate? (I assume it's the same as using paper like I did in gen chem but I'm not sure I know why it shouldn't be allowed to reach the top... what would happen?) 2. why
  48. chem

    Ionic bonds and covalent bonds, which one is the stronger. My present teacher said that covalent bond is the strongest one. I learned ionic interaction is the strongest and many chem. books say so. Now i am confused. Is my present teacher right. Please
  49. chem lab

    hi im doing a post lab sheet for chem class. and im having a little trouble. i have: temperature 12.6 C -> 285.6 K Time 816 sec but im supposed to find 1/T(K) it looks like my classmate did this: 12.6 x 285.6 = 3598.56 however they gave me the response
  50. chem-repost

    I ddin't know if anybody would look far down to page to help me answer my question but this is what was said so far. Posted by rebekah on Sunday, October 24, 2010 at 4:48pm. Give the general formula for any dialkene; that is, a straight-chain hydrocarbon
  51. another chem question

    Examine the following unbalanced chemical equation: CO(little2) + C --> CO Which of the following is the correctly balanced form of this equation? 2CO(little2) + C --> CO CO(little2) + C -->2CO CO(little2) + C(little2) --> CO CO(little2) + C
  52. Chem

    The correction terms in the Van der Waals equation for a gas are designed to correct A. the pressure term (P +a/V2) for the attractive forces between particles. B. the volume term (V-b) for the finite volume of the particles. C. For the volume term (b) not
  53. CHEM

    A particular coal contains 2.55% sulfur by mass. When the coal is burned, it produces SO2 emissions which combine with rainwater to produce sulfuric acid. Determine how much sulfuric acid (in metric tons) is produced by the combustion of 1.1 metric ton of
  54. Chem (but i think its physics)

    Ok so this problem appeared in my online chem homework, but it looks alot more like a physics problem. I have no idea how to do it A 203 lb man eats an order of French Fries consuming 250 Cal of food energy. Afterwards he feels guilty and decides to work
  55. chem

    i need help
  56. Chem

    C2
  57. chem

    what does S.T.P mean?
  58. Chem

    Im studying for the MCAT and i found this question in my old chem book. i can't figure out how to derive the formula they are talking about... Nitrogen monoxide reacts with oxygen to give nitrogen dioxide. 2 NO(g)+ O2(g) --> 2 NO2(g) The rate law is
  59. Chem

    Im studying for the MCAT and i found this question in my old chem book. i can't figure out how to derive the formula they are talking about... Nitrogen monoxide reacts with oxygen to give nitrogen dioxide. 2 NO(g)+ O2(g) --> 2 NO2(g) The rate law is
  60. gr. 12 chem

    what is none and decane used for and why is this appropriate for each use?
  61. chem

    2.0 x 10(exp-13) km/0.01=
  62. chem

    what is the % of CI in CCl4?
  63. chem

    What is the pH of 0.2 M HN3?
  64. chem

    1m^3= cm^3 is it 1000000cm^3?
  65. chem

    6.46g
  66. chem

    need help on chemistry below
  67. chem

    thank you for your help but how would i be able to find that out
  68. Chem.

    What is the name for H3CF?
  69. chem

    Br + CHCOOH
  70. chem

    H2 + H2O ->??
  71. College CHEM

    Name for Sn(BrO3)
  72. Chem

    5.04x1034 atoms of Zn
  73. chem

    what is(2.25x10*3)(4.80x10*4)=
  74. chem

    What is the pH of a 0.22 M solution of HClO4?
  75. chem

    What is the formula to calculate qp?
  76. Chem

    is ethanol chiral?
  77. chem

    why is hexane known as hydrocarbon?
  78. chem

    oh thanks If you have CH4, does the 4 apply to both the C and H or only to the H? It is the H that is four. only the H
  79. Chem

    What is the PH of 0.40 M Na2SO3? (K1 for H2SO3 = 1.5 * 10^-2; K2 = 1.0 * 10^-7
  80. chem

    In Fe(NO3)3, how many Fe atoms are there? One, three N, and 9 O. thank you
  81. Honors Chem B

    Thank you bobpursley!
  82. Chem

    What is saponification? What commercial use does it have?
  83. Chem

    The ka expression for HTe- is?
  84. CHEM

    Why is CH 4 nonpolar whereas CH 3 Cl is polar?
  85. chem

    NaNO3 + H2O >
  86. Chem

    How many stereoisomers are there for 1,2-dichlorocyclopentane
  87. chem

    How many different possible tetrachlorobenzens exist?
  88. chem

    What is the [OH-] for a solution at 25°C that has [H3O+] = 8.23 × 10-2 M?
  89. Chem

    How would you figure out PPM when given mL and mg?
  90. chem

    does (aq) mean a precipitate or (s) Ie BaCl2(aq) Mg(OH)2
  91. chem

    what is the name of ONO and what is its charge
  92. Chem

    1.00 * 10^26 molecules of Tl to moles
  93. chem

    How any orbits 4p subshell?
  94. Chem

    What is the PH of 0.0100M H2SO4?
  95. chem 1010

    Thank you for your help Dr.Bob
  96. Chem

    Something with L-carvone or D-carbon?
  97. Chem

    Cd(s)+Cu+(aq)→Cd2+(aq)+Cu(s)
  98. college chem

    a compound containing
  99. Chem

    is 3.00 x 10^8 m/s the speed of light
  100. chem

    Al(CN)3.8H2O What is it named?