Popular questions and responses by DrBob222
  1. To Morgan

    Where are you getting all of this stuff? What university/college? Where do the exercises(questions) come from? What sources to you have for study? What percentage are you getting from Jiskha? Thanks. I'm just curious.

    asked on December 12, 2014
  2. Chemistry

    Count the electrons. HCN I see 10. NCCN I see 18. What noble gas has an atomic number of 10? of 18? State the noble gas whose electron configuration is attained in the following Lewis structures. a) H:C:::N: (cyanide) b) :N:::C:C:::N: (cyanogen)

    asked on February 6, 2007
  3. Chemistry

    delta T = ikfm delta T is the amount f.p. is lowered. i is the number of particles; i.e., Na3PO4 will have i = 4 (3 for Na and 1 for PO4). m is molality. k is a constant and need not enter into the calculations. Arrange the following solutions in order of

    asked on January 21, 2007
  4. To Annabelle

    I have removed your extraneous answers from the last four or five posts. Please do not respond if you don't know the answer. If you persist in responding with rubbish you will be banned from this site.

    asked on November 10, 2012
  5. To Derr

    You have made a couple of uncalled for comments to a couple of questions. Your remarks are not only not necessary but they take away our time in reading them to know they are nonsense. This board tries to help students. You are helping; please desist with

    asked on May 12, 2008
  6. please read

    As an interested bystander, let me add just one bit to the replies and counter responses. It IS NOT correct Internet behaviour to post full name, address, etc etc. Predators are everywhere. Student's should not use their real name (first name is OK) but

    asked on November 13, 2006
  7. science( chem)

    Basically what color is yellow when they say "Yellow"? The titrations I have done are light yellow when approaching the end point but whatever color you see is what you get, I suppose. So titrate to a very light color. Would the extra 5ml of starch

    asked on July 18, 2007
  8. chem

    frozen carbon dioxide, CO2. what is dry ice

    asked on April 21, 2007
  9. MSDS sheet

    Does anyone know where I can get a free MSDS sheet WITHOUT giving my complete biography? I don't mind an email address and even a name but land mail address, phone number, number of adults in household, cars in household, fax number, and other garbage is

    asked on October 14, 2006
  10. Chemistry

    delta G reaction = delta G products - delta G reactants. Hydrogen peroxide is used as a bleachin agent, a disinfectant and medicinally as a topical antibacterial agent. Hydrogen peroxide decomposes according to the reacton 2H^2O^2(l)-->2H^2O(l)+o^2(g) A.

    asked on May 15, 2007
  11. chem

    Kw = KaKb. With this equation you can convert any Ka to Kb and the reverse. Codeine (Cod), a powerful and addictive painkiller, is a weak base. a) Write a reaction to show its basic nature in water. Represent the codeine molecule with Cod. b) The Ka for

    asked on April 28, 2007
  12. chem

    Sorry about that. I don't know why it did that? I will try to recap the two or three sentences I read. The oxygen molecules dissolve in H2O in the spaces between the molecules of H2O. Liquid water consists of a network of hydrogen bonded water molecules.

    asked on April 19, 2007
  13. chemistry - s103

    Post your question. Perhaps we can help. Is there anyone out there who understands Q5 of tma06 for s103? I don't understand a word of it hi i think that the functional group are NH2 and the c=0 does anybody come up with that they to me are all amine part

    asked on March 8, 2007
  14. chemistry

    I don't think there is any benzene in Elmer's glue. In fact, I suspect finding something with benzene in it will be tough to do unless you have some OLD OLD bottles of something. Its a carcinogenic thing. If you are looking for something aromatic (meaning

    asked on February 5, 2007
  15. Chemistry

    Let's do 1 and 2 and go from there. I will get you started. Take a 100 g sample. That means we have 19.9% C = 19.9 g C 46.7% N = 46.7 g N 6.67% H = 6.67 g H 26.7% O = 26.7 g O Find mols of these amounts. mols C = 19.9/12 = 1.66 mols N = 46.7/14 = 3.33 mols

    asked on February 3, 2007
  16. Chemistry Equation(again)

    What I wrote is the balanced ionic equation. The ++ are written as exponents and could be written as we usually do it as Cu^+2 + Zn ==> Zn^+2 + Cu. For the molecular equation, it is Cu(NO3)2 + Zn ==> Zn(NO3)2 + Cu So the ionic equation for adding

    asked on January 7, 2007
  17. Chemistry!

    When 2.5g of NaOH were dissolved in 49.0g water in a calorimeter at 24.0 C, the temperature of the solution went up to 37.1 C. a. Is the solution reaction exothermic? Why? The temperature or the water went from 24.0 to 37.1 which is an increase. If the

    asked on December 4, 2006
  18. kilauea

    I see in the news reports that when the lava hits the ocean there is a spray of HYDROCHLORIC ACID. I don't see any way HCl can be formed. Acid, yes. H2SO3 yes. But not HCl. Any comments? Thanks.

    asked on May 29, 2018
  19. @shenaya

    I posted a response to your Ksp/K but I was late doing it. Hope you saw it.

    asked on May 25, 2017
  20. To Mara

    I have posted an answer for your question on acetone and ethanol (equimolar solutions) to equal 1000 mL. It's back on page 3 at the time I write this. Post your work if you get stuck and I suggest you repost at the top of the board. We will find it easier

    asked on October 25, 2016
  21. To Kibito

    I posted a response to your last two queries and now I can't find your original question nor my answers. Did you get everything taken care of on that H2S problem? My final answer was x = 0.00167 but also talked about how to solve the cubic equation using a

    asked on May 19, 2015
  22. To Kelsey

    Your buffer problem has moved down quite a bit but I've responded to your last response with my own response.

    asked on May 12, 2015
  23. To Tracey

    Regarding the FeO==> Fe(OH)3 problem below, take a look at the additional post. Here is the link. http://www.jiskha.com/display.cgi?id=1429650539

    asked on April 21, 2015
  24. To Jaimi--chemistry

    I responded to your post(the one on ratio of +/- charges) that's way down the list (I think on page 2 or 3 by now). Here is a link. http://www.jiskha.com/display.cgi?id=1429203638

    asked on April 16, 2015
  25. To Michelle

    I posted a response to that potentiometric analysis problem but it's pretty far down the list. Let me know if you can't find it and I can help.

    asked on April 15, 2015
  26. To Devron

    Since you are a biochemist please look at the post below by C. I tried answering the question but I really don't understand the question. Perhaps you can help.

    asked on January 18, 2015
  27. TO M--urgent

    I named that compound as cis and it should be trans. The I atoms are on opposite sides and that's trans, not cis.

    asked on September 27, 2014
  28. To TOM

    I accidentally erased your post on the hydrolysis of various anions. The answer is Kb(for the anion) = (Kw/Ka for the Ka for the acid) where Ka will be Ka for monoprotic acids, k2 for diprotic acids, or k3 for triprotic acids So to make OH^- the smallest

    asked on April 5, 2014
  29. To Nina

    I think you transposed the numbers for mass proton on your post yesterday which may be the reason you had trouble getting the answer in the book. I've posted a response at the original post which can be found here.

    asked on March 16, 2014
  30. Math

    I have a question my brother asked me but I need a math expert. You have two interlocking circles and the radius of circle B goes through the center of circle A and of course the radius of circle A goes through the center of circle B. The radius of each

    asked on June 25, 2013
  31. To Laura/Joseph

    I have taken care of the answer to the SO3 ==> SO2 + O2 equilibrium problem that we worked on last night about midnight. You should obtain the correct answer now.

    asked on March 9, 2013
  32. To Breanne

    I responded to that chocolate milk/ice problem. Here is a link to it. http://www.jiskha.com/display.cgi?id=1357962576#1357962576.1358029768

    asked on January 13, 2013
  33. To Gabby and Jean

    I have done as asked and worked that Na2C2O4 + LaCl3 problem in some detail. I've posted it at the ogiginal site; here is a hot link to it. http://www.jiskha.com/display.cgi?id=1324010745

    asked on December 16, 2011
  34. To John

    If you have that question about the N2O4/NO2 equilibrium I can help if you re-post. I can't find it. I think you posted it Saturday but it may have been Sunday.

    asked on February 8, 2011
  35. To Rachel

    I'm sorry to take so long to get back. All of the C atoms are sp2 hybridized. There are no sp3 hybridized C atoms Here is a link to that post on Sunday. http://www.jiskha.com/display.cgi?id=1295798102

    asked on January 24, 2011
  36. To CC

    Here is the question you initially posted @ 10:22 last night (Sunday) with my responses. Here are the corrections I made. Check my arithmetic. http://www.jiskha.com/display.cgi?id=1269310966

    asked on March 23, 2010
  37. To Sophia

    Posting the exact question more than once is superfluous and doesn't get an answer any faster. Miranda and another screen name did this yesterday. Perhaps you did all of them. At any rate, just post once please.

    asked on May 18, 2009
  38. To Mary

    Check below for the answer to your buffer question.

    asked on April 14, 2009
  39. Quicken report

    Does anyone know details about quicken investment reports? My investment report suddenly won't work.

    asked on April 10, 2009
  40. To yvonne/GK

    Yvonne. Did you type all of the question about osmosis? correctly? I have struggled with it and something about it doesn't seem right. GK. Doesn't the NaCl enter the equation? And shouldn't the mass MgCl2 be less than 0.5000 gram? The total NaCl + MgCl2

    asked on November 30, 2008
  41. Repost for Dora

    solution is made by mixing 20.0 mL of toluene C6H5CH3d=0.867gmL with 150.0 mL of benzene C6H6d=0.874gmL. Assuming that the volumes add upon mixing, what are the molarity (M) and molality (m) of the toluene For Further Reading * chemistry - DrBob222,

    asked on April 4, 2008
  42. To Jessica

    Sorry, but I made two errors. Monocalcium phosphate is monocalcium monohydrogen phosphate which is CaHPO4. The Ca is +2, H is +1, and PO4 is -3 so the +3 and -3 balance. And Bob Pursley did NOT suggest that name of monocalcium dihydrogen phosphate, he was

    asked on December 16, 2007
  43. To Tammy

    See the answer to the problem you posted about 10E and 11E. I unintentionally put the 10 and 11 as subscripts in my answer to your question last night instead of superscripts as above. The answer I gave you is correct but I should have used superscripts

    asked on October 23, 2007
  44. math

    I would let #1 = x. Then #2 = x+1 #3 = x+2 #4 = x+3 The problem says we want the sum of the first three. That will be x + (x + 1) + (x + 2) and that should be 60 more than the fourth. The fourth is x + 3; therefore, set them equal and add 60 to the fourth.

    asked on August 16, 2007
  45. math

    distance = rate x time or d = r*t car traveling 40 mi/hr goes 40 mi/hr x 1.5 hrs head start or 60 miles head start. Let t = time bus and car travel. car travels distance of r*t = 40*t. Car already had 60 mi head start. Total distance car traveled is 60 +

    asked on August 16, 2007
  46. Chemistry

    -856.7 kJ/mol is delta Gfo. Same book I used for you yesterday. Pretty good freshman text, huh? I think there is a site but this was quicker. Okay, now I need the delta G for SiO2. Maybe you have a website or something. Yes, very good text. Much better

    asked on August 10, 2007
  47. science(chem)

    Breathing too much alcohol or too much HNO3 surely would not be very good but I doubt there would be a reaction that would produce toxic fumes other than the fumes from the HNO3 and/or the ethanol. On similar note, just yesterday an 18-wheeler spilled a

    asked on July 29, 2007
  48. Chemistry

    Do you know how to set up the ICE? That's what you need to do. If you know but are confused, tell us what you don't understand about it. At 55 degrees celcius, the K for the reaction: 2NO2 (g) N2O4(g) is 1.15 Calculate the concentration of N2)4(g) present

    asked on May 15, 2007
  49. chem

    HCl is a strong acid and ionizes 100%. NaOH is a strong base and ionizes 100%. We have no way of knowing the pH of HCl + H2O because the problem doesn't state the amount of HCl added or the concentration of HCl. For the NaOH + HCl ==> NaCl + HOH. NaCl in

    asked on May 15, 2007
  50. Chemistry-

    Yes, both are endothermic; however, the first one is between gases and the second one APPEARS to be (it isn't balanced with charge) a dissociated of a solid. Therefore, the first one will be much more sensitive to pressure changes than the second (if it is

    asked on May 3, 2007
  51. Chemistry

    As I read it, the question provides you with a word description of the production of diesel fuel, gasoline, lighter gases such as ethane and propane, as well as some of the refinery operations such as cracking. Your job is to take this word description and

    asked on April 30, 2007
  52. To Dr Russ

    I hope you come around often. We need someone with a little organic background. Mine is TOO little (and too late!).

    asked on April 18, 2007
  53. chemistry

    It forms NH4Cl, ammonium chloride, which is soluble in the water.

    asked on April 2, 2007
  54. Chemistry

    http://www.google.com/search?hl=en&ie=UTF-8&sa=X&oi=spell&resnum=0&ct=result&cd=1&q=trifluoroacetic+acid&spell=1 What would happen to the strength of acetic acid if the three hydrogens that were on thte adjoining carbon were replaced with fluorines? It

    asked on April 1, 2007
  55. Chemistry

    Think about this. Then let us know what you think and why! The answer should be obvious if you think about it. A liquid in a stoppered flask is allowed to stand at constant temperature entil the liquid level in the flask remains constant. which condition

    asked on March 26, 2007
  56. chemistry

    I think, by convention, most would consider the solvent as the major component and the others as solutes. Actually, however, it dosesn't matter. I just read that when one liquid is dissolved in another, the minor component is usually considered the solute

    asked on February 28, 2007
  57. Chem

    Look on your calculator. You know the definition of pH. It is pH=-log(H^+). Well, we have the same thing in pKa, pKb, pOH, pKw, etc etc. pKsp = -log Ksp. Punch 57.685 into the calculator. Now change the sign to make it negative. Now look for a button that

    asked on February 27, 2007
  58. Math

    Is that 6%/year simple interest? If so, then $500 x 0.06 = $30 for one year. So for 90 days, $530 can't be correct. I would like to have an account that would more than double in a year, much less in 90 days. The Investors Club invests $500 at 6% simple

    asked on February 26, 2007
  59. Throughout your life,who has impacted your life?

    Opinions are ok but anything with identifying information will be removed. In fact, why don't you retype your question and omit the part about including name, address, et al. and we can get someone to remove your original post. ok.thanks,do you think you

    asked on February 9, 2007
  60. To Melinda

    Look at the last response to your U-?? question. I wonder?? That is what my book said...so I really don't know.

    asked on February 8, 2007
  61. chemistry

    Everything is neutral. Touch a table, a chair, a desk, a tree, and you don't get a shock. Compounds are neutral. So Al2O3 must be neutral. Al has a valence of +3. Oxygen has a valence of -2. Now, let's add the charges. 2 Al @ +3 each is +6. 3 O @ -2 each

    asked on February 5, 2007
  62. Chemistry

    Al2Se3 (s) + H2O (sub>(l) ==> Al(OH)3 (s) + H2Se(g) You can see that this reaction produces hydrogen selenide gas. But it will be wet because of the water. I can't draw diagrams on the computer so you will need to research your text and notes to see how to

    asked on February 5, 2007
  63. Chemistry

    You do it by finding Uuh in the periodic table and knowing that it will have chemical properties that are similar to those in the group with it. Here is a periodic table on the web. Find element #116 and observe the other elements in the same group (O, S,

    asked on February 5, 2007
  64. Chem

    The atomic numbers and masses must added up on both sides of the equation just as we must have the same number of atoms on each side of an equation when it is balanced. Ejection of a "thing" with 2 protons and 2 nuetrons is a He nucleus which is an alpha

    asked on February 5, 2007
  65. chemistry

    Look at gold. It has an atomic number of 79. Adding 1 proton would make it have 80 protons and that element (from the periodic table) is mercury. Look up the prices of Au and Hg and compare. Frankly, I would rather have Au (a solid) than Hg, (a liquid).

    asked on February 5, 2007
  66. Math

    3x-4 to y+15 is constant and y=3 when x=2 then when y=12, x equals? My answer was 13. Im not sure how to solve this question. Could you please go through the steps so I can see they match up with mines. My Steps: 3x-y:y+15 The original problem above says

    asked on February 1, 2007
  67. Chemistry (Check)

    Are most factors unity? Is this True or false I'm thinkin true.. The actual size of a measurement multiplied by a conversion factor remains the same, beacause the measurement being converted is multiplied by unity. okay

    asked on January 25, 2007
  68. Reposted - math - Ashley's question

    L=length w=width ============ eqn 1 is 2L + 2w = 28 eqn 2 is w= (1/2)L+2 =========== solve for L and w. Post your work if you get stuck. http://www.jiskha.com/display.cgi?id=1169164168 Posted by Ashley on Thursday, January 18, 2007 at 6:49pm. John made a

    asked on January 19, 2007
  69. vapor pressure

    762 + vp ethanol = total pressure. Dalton's Law of partial pressures. The total pressure in a flask containing air and ethanol at 257C is 882 mm Hg. If the pressure of the air in the flask is 762 mm Hg, the vapor pressure of ethanol is ?mm Hg.

    asked on January 17, 2007
  70. Science/chemistry

    Those are the two COMMON oxidation states. What are the charges of the two ions of copper? +1 and +2. Copper(I) and copper(II). cuprous and cupric.

    asked on January 4, 2007
  71. Chemistry

    This may help a little. Although this may appear to be all about temperature, read thourough it and note that temperature denatures the enzyme and how that affects the K and the Arrhenius equation. (Broken Link Removed) An enzyme gets denatured at high

    asked on December 25, 2006
  72. science

    Try MgBr2 and I expect you can balance it. i got a balancing equation problem i gotta get this to balance Mg(OH)2+ HBr --> MgBr + H20 so far i'v gotten it down to 2Mg(OH)2+ 4HBr --> 2MgBr + 4H20 but it's still not balanced,so can someone please balance

    asked on December 12, 2006

    (aq) means the solution is dissolved in water used as a solvent. (l) means the COMPOUND (not element, usually) is a pure liquid. (g) means gas and (s) means solid. In the equation below, HCl(aq) + NaOH(aq) -->NaCl(aq) + H2O(l)This means that an aqueous

    asked on December 11, 2006
  74. Powers!

    1. Should be 8a15 but I think that is just a typo because the * and 8 are on the same key of the keyboard. 2-4 look ok to me. 5. What you have looks ok to me; however, can't these two terms be multiplied to give 200x8y9 ? Yeah sorry about #1 that's what I

    asked on December 4, 2006
  75. To sam!

    Was the five part unknown question for compounds A through E yours? If so, did you get it answered ok? no it was not mine! can you please check my math? can you please check my math?

    asked on December 4, 2006

    You give up too easily. How? I posted how to get the answer below at the original question. OK but I replied... As did I. Well...I replied...again... Maybe you do understand this for horizontal lines. If you interchange x with y, vertical and horizontal

    asked on December 2, 2006
  77. Naming alkanes

    Its been a long time since I did this but I believe you pick the longest chain. If there are double and triple bonds involved, pick the longest chain that contains the double bond plus single bonds to go with it (but that is for alkenes isn't it?) When

    asked on November 29, 2006
  78. math

    x=12 so x is positive. is this equation negative or postive? 2x=3x-12

    asked on November 28, 2006
  79. Chemistry

    CoCl2 is a compound that is blue when it is dehydrated and pink when in its hydrated form. I have seen a solution of CoCl2 used to paint a coloring book type figure (on paper). This is hung outside and gives a blue color when the air is dry and pink color

    asked on November 16, 2006
  80. science

    No question was posted. Try again.

    asked on November 16, 2006
  81. Water

    One way is to collect rain. Another way is to erect cone shaped metal objects on which water will condense at night and run into a container. There probably are more esoteric systems but this should get you sarted. If you don't have any machines or modern

    asked on November 15, 2006
  82. unscrambling word

    Looks like parade to me. what is this word here are the letter dapear http://www.ssynth.co.uk/~gay/anagram.html That is an easy to use word solver. Paste or type in the letters, and solve! what is the spanish word

    asked on November 13, 2006
  83. science

    Go to www.webelements.com and click on neon (element # 10). You can read all about both physical and chemical properties of neon.

    asked on November 12, 2006
  84. Algebra

    17.5 lbs x 20 min/lb = ??min Notice how the unit we don't want (lbs) cancel leving the unit we want (time in min). A turkey is to be cooked 20 minutes for every pound of weight. How long should the turkey be cooked if it weighs 17.5 pounds? For every

    asked on November 9, 2006
  85. science

    What do you think it does to the surface tension? why does adding soap to water reduce waters cohessiveness?

    asked on November 8, 2006

    Responded to the original post and follow up at original site. If you have trouble finding it I can come back and paste the asnwer here. !

    asked on November 1, 2006
  87. Weighted Averages

    I am assuming this is a 1,000g mixture. 42% H3BO3 = 420g H3BO3/(420g H3BO3+580g H2O)= 0.42 by mass. 420g H3BO3/(420g H3BO3+580g H2O+Xg H2O)= 0.06 Solve for X Check my thinking. Check my work. There is an alternative approach. You want to dilute it by a

    asked on October 29, 2006
  88. To ajones51

    Tough pH question #2 answered on page 2 a/o midnight CDT. It will continue to move as time marches. I hope you see the post.

    asked on October 10, 2006
  89. To Lindz

    If you see this post, respond here for a follow up on previous questions about reactivity to double bonds.

    asked on October 5, 2006
  90. Chemistry

    Here goes. I am NOT an organic chemist so please obtain other sources for information; i.e., don't take my work as gospel. a) I believe the second one you list is more reactive because the first one is sterically hindered due to the isopropyl group. And

    asked on September 27, 2006
  91. To Sheryl: polarity

    The exact question is: Benzyl alcohol (bp 205 degree C) was selected by a student to crystallize fluorenol (mp 153-154 degrees C) because the solubility characteristics of this solvent are appropriate. However, this solvent is not a good choice. Explain.

    asked on September 27, 2006
  92. Normality headache(thx BobPursley and Dr.Bob)

    And many thanks for the thanks. All of us like to think that we offer a helping hand. Both individually and as a group I think this group does that. Good luck to you with your finals and I hope we see you when your next semester/quarter starts. And many

    asked on June 16, 2006
  1. Chemistry

    H3BO3 is a weak acid because it ionizes to provide H^+ in solution. Ka1 = 7.2E-10. Ka2 is 1.8E-13 but for pH of this solution need not be considered since it is 1000 times weaker than Ka1 and contributes very little on its own. ................H3BO3 ==>

    posted on August 7, 2020
  2. Chemistry

    The relative strength is determined by (a) the electronegativity of the central atom and (b) by the number of oxygen atoms. Here is a good description. For this series HClO4 is the strongest followed by H2SO4 followed by H3PO4.

    posted on August 7, 2020
  3. Science

    This question is not complete.

    posted on August 7, 2020
  4. chemistry

    ZnCO3 ==> ZnO + CO2, then ZnO + 2HCl ==> ZnCl2 + H2O mols Zn = grams/atomic mass = 12.5/65.4 = about 0.2 but that's just an estimate. You need to recalculate all of these numbers for a better answer to this question. Looking at the equation 1 mol ZnCO3

    posted on August 6, 2020
  5. Chemistry

    You must have some data such as rate of reaction, concentration of reactants, etc. Without that we're in the dark.

    posted on August 5, 2020
  6. Chemistry

    NaOH(aq) ==> Na^(aq) + OH^-(aq)

    posted on August 5, 2020
  7. Chemistry

    Initial (N2) = 1 mo/L Initial (H2) = 1 mol/L ........................N2 (g) + 3H2 (g) -> 2NH3 (g) I.....................1.0............1.0................0 Change...........-x.............-3x..............2x

    posted on August 4, 2020
  8. Science

    In a simple what? % efficiency = (output/input)*100 80 = (output/120)*100 Solve for output.

    posted on August 2, 2020