Questions Asked on
February 7, 2007

  1. chemistry

    how many molecules are present in 4.25 mol if CCl4? 1 mol = 6.022 x 10^23 molecules Therefore, how many molecules are in 4 moles? I don't have a calculator to figure out that problem, but I do understand it. i mn

    asked by larry
  2. Joint variation

    A variable 'f' varies jointly as 'g' and the square of 'h' and inversely as 'j'. If f=-14 when g=5, h=8, j=20, what is 'f' when g=4, h=6 and j=9? Thanks. F=Constant*gh/j Use the data for determine the constant. Then, use the second set of data to determine

    asked by Jen
  3. Chemistry

    How much Ca(NO3)2 should be weighed out to have 0.650? To have 0.650 what of what. Do you want 0.650 g Ca?

    asked by Bob
  4. math check please

    1.Write 4x4x4x4x4 as a power of 4. Answer: 4^5 2. Evaluate. 72 divide 8-9 divide 3 Answer: 0 3. Give the place value for the indicated digit 8 in the number 138,350 Answer: Thousands 4. Fencing a rectangular field that measures 37 ft by 27 ft How much

    asked by tara
  5. chemistry

    Is C7h16 + O2 = 7 CO2 + 8 H2O a balance chemical equation? C balances. H balances (you should capitalize it). O is not balanced. You need a coefficient of 11 for O2. Check that.

    asked by larry
  6. Science

    COMPOUND 1 CH2=CH-CH-OH ________| _______CH3 COMPOUND 2 _____________O ____________// CH3-CH-CH2-C _____|______\ ____CH3______OH *Now, I must: Identify any functional groups in these compounds and name them. The functional group in 1 is the OH which makes

    asked by Shane
  7. Sociology

    Okay... here's the assignment. I've been trying this for a week and I'm screwed. Spend 30 minutes on each of these sites and answer the following questions in a 3-5 page paper, APA style. pchrgaza (dot) ps memri (dot) org/archives (dot) html In this

    asked by Marie
  8. science

    how is grass better than people grass is better than people because we need the grass to survive. The grass gives off oxygen allowing us to breathe.

    asked by brian
  9. mathmatics probability

    I am having with the following questions and was wondering if someone might be able to show me a step by step solution to arrive at the answer. They are from Probablity and Statistics for Enginnering and the Sciences by Jay Devore 6th Edition 62) An

    asked by ajones51
  10. Quadratic Equations

    Ok, I am supposed to find out what the variables are by factoring and finding square roots. I couldn't find the right factors of a and c that added up to b in the equation (did that make sense?). Please help me find them! TYVM -5n+6n^2-4=0

    asked by Emily
  11. chemistry

    hi, Can you please double check to see if i have got this right? Is the empirical formual for oxide of arsenic As2O5? Cheers ;) Arsenic forms two oxides with oxygen. One is As2O5, the other is As2O3. I'm glad you posted today; please tell your friend you

    asked by bertie
  12. Chemistry

    I have this question in front of me concerning Methanol (CH3OH) & how geseous methanol is formed via the following thermochemical equation: CO(g)+2H2(g)¡êCH3OH(g)∆H=-90kJ . Now, it asks me (explanations should show a clear understanding of how Le

    asked by Travis
  13. half-life

    1. The half-life of a first-order reaction is 9.89 minutes. How many minutes will have elapsed after 27 half-lives? My answer is 267.03. 2. The half-life of a second-order reaction is 2.508 days. How many days will have elapsed after 8 half-lives? My

    asked by Issac
  14. photometry

    which type of binary can have their sizes measured directly by photometry

    asked by bolometric
  15. m type star

    what is the typical main sequence lifetime of a M-type star? Thank you for using the Jiskha Homework Help Forum. Here is a nice site for astronomy:

    asked by bolometric
  16. Chemistry

    What is the empirical distinction between emission and absorption spectra? In general terms, how did Niels Bohr explain each of these spectra? In general terms, emission spectra are obtained when the electron is at a high energy level and it falls to a

    asked by Raj
  17. chemistry

    Can someone define the mole concept? The mole is a number. A dozen eggs is 12 eggs. A gross of anything, pencils for example, is 144. A ream, of paper for example, is 500 sheets. A mole of anything is 6.02 x 10^23 of those anythings.

    asked by larry
  18. math

    how do you do fractionation? huh??/ What grade are u in?

    asked by Nikki
  19. Math for Chem Lab

    There are two ways in which you can obtain results from a completed graph. One is by interpolation and the other is by extrapolation. What is the difference between these two terms and which one do you believe may lead to erroneous conclusions and why? My

    asked by Marisol
  20. science

    how many helium atoms must undergo fusion at 100 million K in the helium flash?

    asked by bolometric
  21. question

    My question is inregards to why is it that all of my questions that i've posted up here in this website and the answers that i've received show up when i search on the internet. For example if i go to the website askjeeves and type in religion my name

    asked by Kailin
  22. Science

    List ways simple plants affect your life each day. (HINT: Where do electricity and heat for homes come from?) food, heat and electricity(from fossils and coal and oil), cars (gasoline from oil), etc.

    asked by Jessica
  23. Please Check My Math Work

    a^2 - 2ab - 15b^2 This is what I got: (a-5b)(a+3b) Correct! x^4+2x^3-4x^2-5x-6 DIVIDED BY x^2+x-2 My answer: x^2+x-3 remainder of -12\x^2+x-2

    asked by Margie
  24. debating on

    is human better than grass (opposed) Grass is better because without it we would be dead right now! The grass gives us oxygen to breathe! GRASS MUCH BETTR

    asked by tas
  25. nutrition

    what are features of artificial sweeteners? what are general features of sugar alcohols? do they promote high or low glycemic index, constipation, dental caries or fewer GI side effects then alternative sweeteners?

    asked by susan
  26. More Math To Check Please

    4c^2 - 12c + 9 This is what I got: (2c+3)(2c-3) *Is that correct.? No, it is (2c-3)^2.

    asked by Margie
  27. ????Math Question????8th grade adv.math

    Algebra! How is the distance formula and the pythagorean theroem similar? The distance formula follows from the pythagorean theorem. You have to apply it twice: If (x1, y1, z1) are the coordinates of a point 1 and (x2, y2, z2) are the coordinates of point

    asked by Alex
  28. Please Check This 2!

    p^4-1=(p^2)(p^2+1) Typo? p^4-1=(p^2-1)(p^2+1)

    asked by Margie
  29. math

    I suggest you Google each of these people. You can search for the name bio Or you can search for the name height weight. for math i have to do a graph of some sort, so i chose to do a graph of famous ppls heights and weights, so i was wondering do you know

    asked by Ms. Sue
  30. Mathematics

    I have this question on tesselations, I got some homework and one of the questions are: A tesselation with the notation of schlafli of {3,3,4,4}. What formes are at the vertex. Draw a tesselation of it. I have been trying to figure this out for 30mins now

    asked by Stine
  31. English

    Can someone help me with this poem? "From the Dark Tower" by Countee Cullen. I don't know what "dark tower" refers to. =)

    asked by Lisa
  32. Economics

    The task of my assignment was to calculate the Nominal GDP, given the GDP deflator and the Real GDP. This is what I got. GDP Deflator Real GDP Nominal GDP 0.9 600 540 1.0 600 600 1.1 600 660 The second part of the question asks what is happening in terms

    asked by Freddy
  33. Chem

    What is the volume of 0.10mole of a gas at STP 1 mol occupies 22.4 L at STP. so .10 of a mole would be 2.24L of a mole of gas. How can I construct a cube that has that same volume. Right. 2.24L is 2.24 x 1000 cc/L = 2,240 cc = 2,240 cubic centimeters. You

    asked by ezzy
  34. Physics

    in the equation w= fd it is assumed that the force varies and is exerted in the direction of displacement... true or false? Yes. Force is measured in the direction of displacement.

    asked by Shelley
  35. Euro History - Politics

    What was the political structure of Europe like during Age of Metternich and the Age of Realpolitik? Similarities, differences. How did it effect Europe? These sites will help you answer this question.

    asked by Jim
  36. Physics

    1.There are four charges, each with a magnitude of 2.5 µC. Two are positive and two are negative. The charges are fixed to the corners of a 0.29 m square, one to a corner, in such a way that the net force on any charge is directed toward the center of the

    asked by Todd
  37. diversity

    This is a group with distinct national origins or cultural patterns. For example, Norwegian Americans belong to this type of group. Thank you for using the Jiskha Homework Help Forum. Do you mean "ethnic groups?"

    asked by Robert
  38. electricity

    Is there any data about the use of nichrome heating, for instance: a nichrome element in the cables of electric kettles, geysers and spiral stove? What do you mean by "data"? What physical data are you looking for: resistivity?

    asked by tigger needs help
  39. Science help

    A drop of oil volume 0.05cm^3 is released from a medicine dropper on to a calm surface of a pond where it spreads out to cover an area of 40cm^2. Assume that the oil film has a uniform thickness equal to the diameter of an oil molecule. I see there is an

    asked by Lucy
  40. Science

    What is the structural formulae for the equation for the hydrolysis of lactose?

    asked by Samantha
  41. biology

    How can an understanding of the "mortality factor" lead to a successful biological control of pests in agriculture & horticulture? Check these sites.

    asked by Ryan
  42. erosion

    Explain why erosion is less of a problem in the west than the east Erosion by water is less in the west, because there is less rain. In the west, erosion by wind is greater, however, wind erosion is very small when compared to water erosion.

    asked by oliver
  43. SCIENCE - Pls HELP

    A proton (with a mass, mp = 1.673 x 10^-27 kg & electrical charge, e = 1.602 x 10^-19) and an electron (with a mass, me = 9.109 x 10^-31 kg & electric charge -e = -1.602 x 10^-19) are not moving & at a distance of 1.000 x 10^-10 m apart.... (assuming the

    asked by OLIVIA
  44. science

    I know that every element has only a certain set of allowed energy states & that the exact energy of these states depends upon the number of electrons, but why is the colour of the light emitted by an element (in GASEOUS STATE) characteristic of the

    asked by duncan
  45. The rubaiyat

    Take one of the verses from "The Rubáiyát" and rewrite it in modern, informal English. Your verses should have a title and be four lines long, written in iambic pentameter, in AABA. The verse I'm using is: "Some for the glories of this world; and some

    asked by Claire
  46. Generalization essay

    "In this exercise you'll write an essay supporting a generalization you've stated about some topic." Any ideas for generalizations? I have to list 5 and use one. A generic generalization is the most common type. All dogs bite. Here is a good definition.

    asked by Claire
  47. geography

    how big did the rainforests start out to be at the begining of time? At the beginning of time, there were no forests, only microorganisms. For information about the evolution of rainforests, check this site.

    asked by cantsay
  48. math

    If you add two-thirds of a number to the number itself, you get 40. What is the number? I do not know how to set it up? 2/3n + n = 40 Solve for n. I don't know but thak you sooooooooooo much for helping me on my mixed #'s!!!!!!!! Good Luck!!!!!! I don't

    asked by catalina

    Given assumed valencies: H=1, N=3, & C=4 i am now required to draw the structural formulae of HYDROGEN CYANIDE and CYANOGEN. H:C:::N is the Lewis electron dot structure. If you want to use "sticks" as a bond instead of two electrons, one stick stands for

    asked by MARK

    What type of bonding holds the compound, sodium cyanide, together? The CN bond is covalent. The Na to CN bond is, in most minds, an ionic bond. The electronegativity of C is about 2.1 and that of Na is about 1; therefore, with a difference of about 1 it is

    asked by MARK
  51. Biology

    What is the structural formulae for the equation for the hydrolysis of lactose?

    asked by Samantha
  52. Science

    In no more than three sentences I must state the "Hubble relationship" in words AND quantify numerically what it says about the "speed of recession" of distant galaxies (i am to include a definition of the "unit one parsec" in this 3-sentence answer) - CAN

    asked by Anonymous
  53. biog

    When Was Oprah Winfrey Born? Look her up here: =)

    asked by Kierra
  54. Inverse variation

    A variable 'm' varies directly as 'a' and inversely as 'b'. If m=6 when a=7 and b=4, what is 'm' when a=9 and b=12? M= constant*a/b Find the constant from the first set of data, then, using that, find m in the second set.

    asked by Jen
  55. Art & the Bible.

    I need to write a short essay about the Bible's influence on an artist. Listed are Michelangelo, da Vinci, Durer, Rembrandt, Rubens, El Greco, and Pippin. I've searched with google, encarta, and through some others and I can't find a website that tells me

    asked by Claire
  56. ethics

    She is a very capable black woman. How would I make this nonracist and nonagist? She is a very capable person.

    asked by kim
  57. Solving rational inequalities

    problem #1 (1+x)/(2x+3) 2 graphically TIA please ignore this

    asked by Jen
  58. Economic

    All of the following refer to the Economy of Ecoland: - GDP in 1990 is $1000 - Annual inflation is 5% per year from 1991 - 1995. From 1996 - 1999, inflation is 10% per year - Real GDP grows at 2% every year a) Calculate real GDP from 1990 to 1999 b)

    asked by Freddy
  59. World Studies

    True or False. A democratic form of government is one in which a president holds the most power. Read carefully. =)

    asked by Emily
  60. World Studies

    What are some important things that can be found in Washington D.C.? White House Capitol Building Library of Congress Supreme

    asked by Emily
  61. math

    1 1/2 * 3 1/5 = 1 1/2 = 3/2 3 1/5 = 16/5 Multiply numerator and denominator to arrive at the answer. Be sure and reduce the fraction if possible. Please help Angelina!!!!!!!!!! With Math.

    asked by laura
  62. solving rational inequalities

    1/(1+x^2) < 1/2 TIA

    asked by Jen
  63. Math,correction

    direction state : solve each system by addition. if a unique solution does not exist, state whether the system is consistent or dependent. NOw the problem looks like this: 2x+3y=1 5x+3y=16 the answer that I got was this: for variable x = 5 y = -3 which is

    asked by jasmine20
  64. Math

    How would i go about finding the x and y intercepts of this eqaution? f(x)=3x/4x+2

    asked by Mant
  65. research paper

    I need an attention graber to start my paper off. It's on global warming and its effects on the environment. Any help? Here are some blog posts that might give you some ideas:

    asked by sam
  66. chemistry

    Consider the equilibrium, A + B C, with K=32.217 and initial concentrations of A,B, and C, of 3.665M, 0.883M, and 3.925M, respectively. What is the equilibrium concentration of B 3.665 0.883 3.925 A + B = C Keq=(C)/(A)*(B)= 32.217 Q =

    asked by Rob
  67. Pre-Calc

    How do I solve this? My work has led me to a dead end. tan(45-x) + cot(45-x) =4 my work: (tan45 - tanx)/(1+ tan45tanx) + (cot45 - cotx)/(1 + cot45cotx) = 4 (1-tanx)/(1+tanx) + (1-cotx)/(1+cotx) = 4 Then I found a common denominator, giving me this:

    asked by Jess
  68. math

    what does / mean in this equation =(7+45)/2 Divided by. "The quantity 7 + 45 (which would be 52) divided by 2"

    asked by victoria
  69. please check my math

    2/3 + 1/5= 13/15. Is that right or can it be Reduced? You're good to go. That is correct... and 2nd question: It can't be reduced.... Good Job!

    asked by Angelina
  70. pre-calc

    Solve: cos(2x-180) - sin(x-90)=0 my work: cos2xcos180 + sin2xsin180= sinxcos90 - sin90cosx -cos2x - sin2x= cosx -cos^2x + sin^2x -2sinxcosx=cosx I'm stuck here. I tried subtracting cosx from both sides and making sin^2x into 1- cos^2x, but I still can't

    asked by Jess
  71. DrBob222

    On Monday you helped me to understand and answer the one question, but I am not too sure if they want all the calculations that you answered... regretably, I am still a bit lost with these! Below is the question as it is printed: The isotope caesium-137,

    asked by Mary
  72. literature

    Can you please help me make new words from the following: views, player, remote, exits, lacees and newer. I had fifty and just can't figure these out. Thank You...........Destiny 5th grade See answer above -- same question posted by Anonymous! =)

    asked by Destiny
  73. science

    how do i calculate the mols of sulfuric acid ? mols = grams/molar mass

    asked by Deon
  74. literature

    Please provide me with other words using the following: views, player, remote, exits, laces and newer. Thank You. To find synonyms for any word, you need to use a thesaurus: (Scroll down a bit to find the

    asked by Anonymous
  75. Calculus/College Algebra

    I'm so lost. We're working on limits for this assignment and I get that, but my difficulty lies in breaking down the original problem. The problem is: Find the limit: lim (x->5) The numerator is (the square root of 9-x) -2 and the denominator is x-(the

    asked by Amy
  76. Science

    What's the number of stage micrometer units in 10 ocular units using 4x, 10x, and 43x objectives ?

    asked by Tay
  77. Precal

    how to express 3+4i in polar form

    asked by Icon44
  78. chemistry

    105 grams of MgCl2 contains how many mols of MGCl2? mols = grams/molar mass Better get your calculator.

    asked by larry