Posts by trixie

Total # Posts: 133

  1. English 10 A

    I am doing the Character Analysis Portfolio, and need to make a thesis statement, answering the following questions: Why is this character significant to the plot of the story? How does this character contribute to the development of a central theme? Could someone help me? I ...
  2. MATH-Please Help me

    a menu which serves 4 people requires 3 cups of flour.how many cups of flour are needed for the menu to serve 12 people?
  3. Math

    a menu which serves 4 people requires 3 cups of flour.how many cups of flour are needed for the menu to serve 12 people?
  4. finance

    Chip’s Home Brew Whiskey management forecasts that if the firm sells each bottle of Snake-Bite for $20, then the demand for the product will be 15,000 bottles per year, whereas sales will be 91 percent as high if the price is raised 11 percent. Chip’s variable cost ...
  5. finance

    5.Capital Co. has a capital structure, based on current market values, that consists of 21 percent debt, 9 percent preferred stock, and 70 percent common stock. If the returns required by investors are 10 percent, 12 percent, and 17 percent for the debt, preferred stock, and ...
  6. math

    use substitution to solve this linear system: 8x + y = -458 -5x + 3y = 221
  7. math

    no idea . please help!
  8. math

    Model this situation w/ a linear system: Melissa borrowed $10, 000 for her university tuition. She borrowed part of the money at an annual interest rate of 2.4 % and the rest of the money at an annual rate of 4.5 %. Her total annual interest payment is $ 250.50 a.) a + b = 10 ...
  9. math

    Sales clerk at an appliance store have a chance of 2 payment: Plan A: $580 every 2 weeks plus 4.2 % commission on all sales Plan B: $880 every 2 weeks plus 1.2 % commission on all sales a) Write a linear system to model this situation b) Graph the linear system in part a c) ...
  10. math

    will it work if i write : they have the same slope and are identical. Both have the slope of 2/5?
  11. math

    Explain what happens when you try to solve this linear equation using an elimination strategy. What does this tell you about the graphs of these equations? -8x + 20y = -40 24x - 60y = 120
  12. math

    Model this situation w/ a linear system: Melissa borrowed $10, 000 for her university tuition. She borrowed part of the money at an annual interest rate of 2.4 % and the rest of the money at an annual rate of 4.5 %. Her total annual interest payment is $ 250.50
  13. math

    please get back asap
  14. math

    is the answer 3x -2y -17= 0?
  15. math

    write an equation in general form for the line that passes through A(3,-4) and B(11, 8)
  16. math

    Create a linear system to model this situation. Then use substitution to solve the linear system to solve the problem. - Bobbie has been saving dimes & quarters to buy a new toy. She has a total of 28 dimes and quarters, with a value of $4.30. How many of each type of coin ...
  17. math

    cashew nuts sell for $21.00/kg. Brazil nuts sell for $15.00/k. A distributor sold a total of 120 kg of nuts and Brazil nuts for $2244. What mass of each type of nut was sold?
  18. algebra 2

    How do you find the points of intersection, if any, of the equations: x^2 + y^2 = 5 x - y = 1
  19. us history

    how was president Woodrow Wilson truly a progressive president?
  20. world history

    i don't get the question because at the time in which they developed, the US didn't even exist.
  21. world history

    the question is: Why is England and France developing into nations important to us? i need websites where i can get information on this please
  22. Chemistry

    I figured out the first one...still struggling with the 2nd...
  23. Chemistry

    Q1. The blood volume in a cancer patient was measured by injecting 5.0 mL of Na2SO4(aq) labeled with 35S (t1/2 = 87.4 d). The activity of the sample was 300 µCi. After 22 min, 12.9 mL of blood was withdrawn from the man and the activity of that sample was found to be 0....
  24. Chemistry

    I also posted the above well before Dr. Bob had answered one of my other questions...
  25. Chemistry

    I wasn't talking about DrBob being rude...that would be bobpursely...DrBob has been nothing but helpful while I have used this site as a resource.
  26. Chemistry

    One last question...even though no one seems to be willing to help me out without being rude. The blood volume in a cancer patient was measured by injecting 5.0 mL of Na2SO4(aq) labeled with 35S (t1/2 = 87.4 d). The activity of the sample was 300 µCi. After 22 min, 12.9 ...
  27. chemistry

    Could you please just explain what I am doing wrong so that I can know how to approach these problems? I appreciate the advice and am well aware I need to go to bed...but I have to get these finished and my professor is out of town attending a memorial service and unable to ...
  28. chemistry

    Sleep is a bit of a luxury.....unfortunately I'm one of those students that doesn't have an option of taking a lighter load or working less....luckily I graduate in a few weeks. In the meantime I need to finish these problems so that I can go to bed....but they are due...
  29. chemistry

    Another attempt I made gave me relatively "reasonable" answers...but still doing something wrong. I converted the minutes to days and used that in the rate to find k via k= rate/N ; N being 3.25E18 atoms. this calculated k to be .00145. I plugged this into N'=Ne...
  30. chemistry

    Oh and when I try to put this into my calculator I get 0... sorry if I am not catching on fast enough for some....I worked graveyard last night and Haven't slept in over 35 hours...
  31. chemistry

    A radioactive sample contains 3.25 1018 atoms of a nuclide that decays at a rate of 3.4 1013 disintegrations per 26 min. (a) What percentage of the nuclide will have decayed after 159 d? % (b) How many atoms of the nuclide will remain in the sample? atoms (c) What is the half-...
  32. Chemistry

    A sample of pure cobalt-60 has an activity of 8 µCi. (t1/2 cobalt-60 = 5.26 a) (a) How many atoms of cobalt-60 are present in the sample? atoms (b) What is the mass in grams of the sample? g The way I approached part a was to first convert the microCi into Bq (for a ...
  33. Chemistry

    A certain Geiger counter is known to respond to only 1 of every 1000 radiation events from a sample. Calculate the activity of each radioactive source in curies, given the following data. 580 clicks in 104 s My text barely attempts to explain how to do this problem, and there ...
  34. Chemistry

    A certain Geiger counter is known to respond to only 1 of every 1000 radiation events from a sample. Calculate the activity of each radioactive source in curies, given the following data. My text barely attempts to explain how to do this problem, and there is no example. I am ...
  35. Chemistry

    no problem :)
  36. Chemistry

    Think of the equations you have learned and which variables you have been given. It helps to keep a list of them in front of you so you can quickly figure it out. Then just plug in. If you have P, V, mass, and T....you're going to use PV=nRT...just solve for P PV=nRT is an...
  37. Chemistry

    Nevermind...I realized that the problem I was using as an example called for 1 g of the reactant used....this didn't....so I have my correct answer now. Thanks! Still stumped on my earlier question though...
  38. Chemistry

    How much energy is emitted in each α decay of plutonium-234? (234Pu, 234.0433mu; 230U, 230.0339mu; 4He = 4.0026 mu). I tried finding the difference in mass first: (230.0339 + 4.0026) - (234.0433) = -.0068 mu I then converted from amu to kg by multiplying by 1.6605E-27. ...
  39. Chemistry

    Hmm...I don't know. My webassign is telling me it's not a neutron. Thanks
  40. Chemistry

    Oh i just realized how you typed the equation has the product flipped. so it's 1,1,H + 1,1P --> 2,1H + ? order is A,Z,X where A is mass and X is the particle or element
  41. Chemistry

    neutron was my first answer...i am using +1 e^0 to be a positron though, not electron.
  42. Chemistry

    I know they need to balance out on both sides. I am just confused because I am pretty sure it should be 0,+1, e ...e being X. Webassign is telling me this is wrong but if that's true I don't understand why and need that explained....
  43. Chemistry

    for A, Z, and X I'm typing it in the form A,Z,X (or X as a particle) since I obviously can't do sub or superscript... 1,1,H + 1,1,p --> 2.1,H + ? I thought initially the missing particle at the end would be either 0,-1,e or 0,1,e (beta emission/decay) but apparently...
  44. Chemistry

    How can you tell if [ MnCl6]4- or [ Mn(CN)6 ] 4- has the longer wavelength of light? and then how do you figure out how many unpaired electrons each has?
  45. Chemistry

    Is Zn+2 diamagnetic or paramagnetic? I am a little confused on how to figure this out and I'm finding inconsistent answers when I tried to look this up. Thanks!
  46. Chemistry

    How can you tell if [ MnCl6]4- or [ Mn(CN)6 ] 4- has the longer wavelength of light? and then how do you figure out how many unpaired electrons each has?
  47. Chemistry

    Trying to name this compound and figure out its oxidation state [ CoBr2(NH3)3(H2O) ]+ I came up with triammineaquadibromocobalt(II) ion with a +3 oxidation state...but not sure if this is right... similarily for [Fe(ox)(Cl)4]3- I came up with tetrachlorooxalatoferrate(IV) ion ...
  48. Chemistry

    Which one of the following combinations of reagents will result in a spontaneous reaction? A) Al(s) + CuCl2(aq) B) Al(s) + CaCl2(aq) C) Zn(s) + CaCl2(aq) D) Cu(s) + ZnCl2(aq) I know the answer is A, but what I don't know is why, or how to figure this out. Thanks!
  49. Chemistry

    You know it's second order so your rate=k[NO2]^2 All you do is like you said, find moles, use that to find molarity (convert mL to L) and then plug the concentration into the equation. You're given the k. Same thing with part B, just changing the concentration :)
  50. Chemistry

    All you have to do is find the concentration of OH- and solve for pH (pOH= -log [OH-] nad then 14-pOH=ph [OH-} = Ksp/[M+}
  51. Chemistry

    NVM i was using the pKA instead of pH....i had it right afterall...guess it's just time for bed....
  52. Chemistry

    I figured out the correct new pH for each respective part, but apparently the initial pH i found for the buffer solution is incorrect. I just need help in figuring that so I can calculate the change. I initially thought the buffer pH was 7.38. Thanks!
  53. Chemistry

    for part a I tried using the HH equation, found moles of NaOH and used that for [base] and moles Na2HPO4 as [acid]...i used pKa 7.21...that was incorrect. For part b I used a similar method...plugging in HNO3 as the [acid] and Na2HPO4 moles as [base] the other pka values for ...
  54. Chemistry

    A buffer solution of volume 100.0 mL is 0.150 M Na2HPO4(aq) and 0.100 M KH2PO4(aq). Refer to table 1. (a) What are the pH and the pH change resulting from the addition of 80.0 mL of 0.0500 M NaOH(aq) to the buffer solution? pH pH change (include negative sign if appropriate) (...
  55. Chemistry

    I'm confused how I would use the Ka equation in the HH equation??? I thought HH was just pH=pka + log([base]/[acid]) ...
  56. Chemistry

    Calculate the pH of the solution that results from mixing the following reagents. Refer to table 1. mix 0.189 L of 0.019 M (CH3)2NH(aq) with 0.327 L of 0.011 M (CH3)2NH2Cl(aq) I tried using the Henderson-Hasselbach equation by finding the pKa but it didn't work....I am ...
  57. Chemistry

    Nevermind I got it...I just mixed up my variables a little. thanks!
  58. Chemistry

    I am pretty stuck...not sure if I used the Henderson-Hasselbach the right way and I'm a little confused on how to set up the Ka expression...
  59. Chemistry

    I am trying to use pH=pKa + log(acid/base) to see where that gets me...I'm attempting to find the [base] using the given pH and pKa of 8.69 (for HBrO)...then use the concentration to find the new pH...
  60. Chemistry

    The pH of 0.50 M HBrO(aq) is 4.50. Calculate the change in pH when 6.50 g of sodium hypobromite is added to 110. mL of the solution. Ignore any change in volume. Ka of HBrO is 2E-9 I found the amount of moles used for each (.0547 mol NaBrO, and .055 mol HBrO soln) I'm not ...
  61. Chemistry

    1x10-2 mol of MgSO4 (Ksp = 9) is added to 1 L of water. Will 1x10-5 mol of CaSO4 (Ksp = 10-6) completely dissolve in the solution? I think the answer is yes...because the Q will be less than Ksp of 10^-6?? Which of the following salts would you expect to result in the greatest...
  62. Chemistry (or Physio/Biochem)

    Asthma affects about seven percent of the population. During an asthma attack smooth muscle cells in the bronchi constrict, the airways become inflamed and swollen, and breathing becomes difficult. What effect might an asthma attack have on blood pH? A. pH goes down B. pH goes...
  63. Chemistry

    100 mL of each of the following solutions is mixed; which one of the mixed solutions is a buffer? A) 1.0 M NH3(aq) + 0.6 M KOH(aq) B) 1.0 M NH4Cl(aq) + 1.0 M KOH(aq) C) 1.0 M NH3(aq) + 0.4 M HCl(aq) D) 1.0 M NH4Cl(aq) + 0.4 M HCl(aq) E) 1.0 M NH3(aq) + 1.0 M HCl(aq) I am ...
  64. Chemistry

    Which of the following systems could act as a buffer? A. HCl/Cl- B. NaOH/OH- C. HSO4-/SO4-2 D. H3O+/OH- E. All of the above my guess is C because A and B are too strong, but I am unsure of D. Can someone explain how to think through this?
  65. Chemistry

    Given the equilibrium rxn CF4(g) + 2H2O(l) ⇔ CO2(g) + 4HF(g) ΔH < 0 if pressure is increased by adding argon gas to the equilibrium, I know it doesn't decrease the amount of HF. But if a random gas is added for any equilibrium rxn, will it always cause an ...
  66. Chemistry

    If a weak acid is say only 5% ionized at equilibrium, then the ionization rxn would be reactant favored, correct? I am a little on the fence about understanding this if anyone could better explain why this would be? I am assuming because it is not completely ionized, the ...
  67. Chemistry

    I see how there are the numbers of particles in solution, I am a little confused on how that relates to these properties. My text is pretty brief over this section.
  68. Chemistry

    I am confused about why this is the answer to a practice problem I was given. (answer is c). Could someone explain why/why not for each answer? 2) Solution A is made from 1 L of water and 0.1 moles of Na(CH3COO), and Solution B is made from 1 L of water and 0.1 moles of Na2(...
  69. world history ancient greece

    i need to do an outline of how to organize things for my research report on the Ancient Olympics. How cna i divide up my report?
  70. Chemistry

    Right...I am confused on the solving for x part. Before when I have used this I have always been given ka or kb in order to solve for x. This time I'm not--so I don't know how to set up my equation to find x. Once I have x I know how to do everything else
  71. Chemistry

    Calculate the initial molarity of KNH2 and the molarities of K+, NH3, OH-, and H3O+ in an aqueous solution that contains 0.75 g of KNH2 in 0.255 L of solution. You may ignore the reaction of NH3 with water. I already found the initial molarity, but I am not sure how to find ...
  72. Chemistry

    Calculate the initial molarity of KNH2 and the molarities of K+, NH3, OH-, and H3O+ in an aqueous solution that contains 0.75 g of KNH2 in 0.255 L of solution. You may ignore the reaction of NH3 with water. I already found the initial molarity, but I am not sure how to find ...
  73. Chemistry

    Well I'm not actually making it in a lab...I just don't fully understand the concept of this
  74. Chemistry

    In a .1M aq. soln of NaCN, how would you determine the major species (other than water)? And how would you determine the pH (not exact pH, I just want to know how to know if it is acidic ie. <7, etc). Thanks in advance
  75. Physical Chemistry

    I figured out what I was doing...I ended up using the Van't Hoff Equation and the enthalpies of formation to solve for K at 100 C. This stuff is so time consuming...
  76. Physical Chemistry

    Calculate the equilibrium constant at 25°C and at 100.°C for each of the following reactions, using data available in Appendix 2A. Remember that the organic molecules are in a separate section behind the organic molecules in Appendix 2A. (a) HgO(s) Hg(l) + O2(g) at 25&...
  77. Chemistry Question!!

    When 1.00 g of gaseous I2 is heated to 1000. K in a 1.00 L sealed container, the resulting equilibrium mixture contains 0.830 g of I2. Calculate Kc for the dissociation equilibrium below. I2 <--> 2 I What I did was converted the initial I2 into moles then molarity since...
  78. Physical Chemistry

    When 1.00 g of gaseous I2 is heated to 1000. K in a 1.00 L sealed container, the resulting equilibrium mixture contains 0.830 g of I2. Calculate Kc for the dissociation equilibrium below. I2 <--> 2 I What I did was converted the initial I2 into moles then molarity since ...
  79. Science

    I've heard this one before: "A meteor is a flash of light made by a falling meteorite"
  80. Chemistry

    nevermind--after 50 hours of pulling my hair out I finally arrived at the answer :)
  81. Chemistry

    And when solving for molality do I need to use the formula dT=Kf*molality? Or do I find it independently of this equation?
  82. Chemistry

    I am confused by the 1% by mass part...I don't understand what it really even means or if I am multiplying something by 1% or what? I did eventually realize I had to multiply by 3--I have never seen a problem like that before so I was slow to catch on. Thanks for your help
  83. Chemistry

    A 1.00% by mass MgSO4(aq) solution has a freezing point of -0.192°C. Water has a kf of 1.86 (K·kg)/mol. (a) Estimate the van't Hoff i factor from the data. (b) Determine the total molality of all solute species. I can probably figure out the second part of the ...
  84. Chemistry

    I still need help with this problem... Calculate the concentration of the solution the molality of hydroxide ions in a solution prepared from 9.16 g of barium hydroxide dissolved in 179 g of water I do not know how to approach this...I keep doing something wrong.
  85. Physical Chemistry

    the answer for a was actually incorrect
  86. Physical Chemistry

    Got it. for A i was using molar mass for FeCl3 instead of water..oops. I solved C...but I am still confused with the second question of anyone can help me out... Thanks!
  87. Physical Chemistry

    Calculate the concentrations of each of the following solutions. (a) the molality of chloride ions in an aqueous solution of iron(III) chloride for which xFeCl3 is 0.0195 (b) the molality of hydroxide ions in a solution prepared from 9.16 g of barium hydroxide dissolved in 179...
  88. Physical Chemistry

    Just want to double check...so for KCl, because it is endothermic, my q should then be negative?
  89. Physical Chemistry

    Ok, thanks for your help
  90. Physical Chemistry

    no I didn't get that, but I was adding both 18g of the salt and 190 g of water for the m used in the equation. I'm still a little confused with the signs...I thought if it is releasing heat then q would be negative? I did manage to get the same value for q I just had ...
  91. Physical Chemistry

    Determine the temperature change when 18.0 g of the following salt is dissolved in 190. g of water. The specific heat capacity of water is 4.184 J·K-1g-1. The enthalpies of solution in the table are applicable. Do not take the added mass of the salt into account when ...
  92. Math

    I mean x is greater than or equal to, not less than. sorry.
  93. Math

    Solve the inequality: 2x-1 / 3x-2 < 1 [the < is actually less than or equal to] I got one of the answers, x is less than or equal to 1, but there's another. How do you find that answer? Thanks
  94. american lit. [[10th grade]]

    i need to write an essay about how holden caulfield from the catcher in the rye is fascinated with childhood and innocence. what can i include as examples for that?
  95. english/ literature/ essay

    oh thank you very much! :)
  96. english/ literature/ essay

    any other reasons? i had that reason well something like it...
  97. english/ literature/ essay

    hi i need help with this.. what is the importance of recognizing cultural differences as a young person in today's global society?
  98. algebra review!

    it says write the equation of the vertical line that passes through the point (7,-3). what do i need to start it off? find the equation for the line with undefined slope and passing through the point (-1,-2). what do i need to start that off? what equation do i use to find the...
  99. algebra review

    find the y-intercept of a line that passes through (2,1) and has a slope of -5. i forgot what equation i have to use to find this out. can someone give me which equation i have to use? or all the equations that deal with slopes please
  100. science- bio

    how can traits on a particular chromosome be determined? how can these traits determine the characteristics of an organism? what could happen if a base is out of order?
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