Newest questions posted by kelly
  1. chemistry

    The mixture of 40 ml of water to 160 ml of solution with ph = 8, causes a change in the ph value. What is the value of the new PH. Use Log 2 = 0.3
  2. math

  3. chemistry

    There are 3.01X1023 atoms of gold, 1 mole of platinum, 3.01 moles of silver. Which one contains more atoms
  4. chemistry

    In the chlorine titration of a solution prepared by the dissolution of 0.2110 g of commercial hypochlorite was spent 19.50 ML of sodium thiosulphate solution 0.1002 mol/L. Calculate the percentage of chlorine (35.45 g/mol) in this sample
  5. chemistry

    A silver wire is immersed in a solution containing ions of CU2 + what is expected in this situation? A) no reaction occurs. b) The silver wire is oxidized. c) Copper is deposited on the silver wire. D) The ions Cu2 + are reduced.
  6. chemistry

    A sulphuric acid density solution of 1.38 g/ml has a concentration of 56% w/w. Calculate the amount of moles of the existing acid in 1 litre of this solution.
  7. chemistry

    3.0g of a mixture of potassium carbonate and potassium chloride were dissolved in a 250cm3 standard flask. 25cm3 of this solution required 40.00cm3 of 0.01M HCl for neutralization. What is the percentage by weight of K2CO3 in the mixture? (K = 39, O = 16,
  8. math

    The function f(t) = 24,500(0.84)  models the population of a town t years after 2008. What rate is the population of the town decreasing each year? A. 16% B. 24.5% C. 75.5% D. 84%
  9. Accounts

    Assuming a proprietorship, partnership, and corporation earns equal amount of income and it is distributed evenly among owners, the amount collected by government toward tax will be: Select one: a. highest for proprietorship. b. highest for corporation. c.
  10. Physics

    Complete the sentence(only one word).As the water waves approach the shore they --------- into a medium of lower wave speed(shallow water).
  11. Physics

    Suppose active sonar on a stationary ship is used to determine the speed of a ship that is moving away from it. A sonar ping is emitted at a frequency of 1400Hz and the echo returns with a frequency of 1390Hz.The speed of sound in sea water is
  12. Physics

    An observer is located directly between two speakers located 20 metres apart.Speakers are in phase and both are emitting a sound of 60Hz.How far away from the centre should the observer move to get the first destructive interference?
  13. physics

    Betty's ball and Fred's ball have the same size, but Fred's ball is hollow. Wilma's ball and Barney's ball are scaled down versions of Betty's ball and Fred's ball respectively. They all place their bowling balls on the same pitch incline and release them
  14. physics

    Three particles, each of mass 1.0 kg, are fastened to each other and to a rotation axis by three massless strings, each 0.120 m long, as shown in the Figure. The combination rotates around the rotation axis with an angular velocity of 25.0 rad/s in such a
  15. chemistry

    When 3,3-dimethyl-2-butanone is reduced, the product is a. 3,3-dimethyl-2-butanene b. 3,3-dimethyl-2-butana c.3,3-dimethyl-2-butanol d. 3,3-dimethyl-2-butananoic acid
  16. AP Chemistry

    Consider the following reaction: Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g) 0.103 g of Zn is combined with enough HCl to make 50.0 mL of solution in a coffee-cup calorimeter. As all of the Zn reacts, the temperature of the solution increases from 22.5°C to
  17. Chemistry

    A 100.00 ml of volume of 0.500 M HCl was mixed with 100.00 ml of 0.500 M KOH in a constant pressure calorimeter. The initial temperature of individual acid and base was 23.0 oC. The final temperature after mixing was 25.5 oC. The specific heat of the
  18. Math

    If y5 + 3x2y2 + 5x4 = 49 , then dy/dx at the point (–1, 2) is: –1 11/23 –23/11 –10/3 0
  19. AP Chemistry

    Determine a pH range for which a buffer system containing benzoic acid would be appropriate. Devise a recipe for preparing 1.0 L of buffer solution that contains a total of 0.150 mol of buffer components (acid plus conjugate base) and has a pH of 4.48. The
  20. AP Chemistry

    How many g of C2H5NH3Cl will be needed to combine with 4.7 g of C2H5NH2 to produce 0.250 L of buffer solution at a pH of 10.00? I can do this problem with mL and M but not w/out
  21. PreCal

    a circular arch of length 3ft subtends a central angle of 25 degrees. Find the Radius of the circle I got 6.875 but i think that is wrong
  22. Math- Algebra

    A mother wants to invest $15000 for her children's education. She invest a portion of the money in a bank certificate of deposit which earns 4 percent and the remainder in a savings bond which earns 7 percent. If the total interest earned after a year is
  23. AP Chem

    Calculate the pH and % ionization for each of the following acids.a. 0.15 M HNO3b. 0.10 M HCNc. 0.40 M HFd. 0.10 M HClO2 I have no idea how to do this? In clas we had a Ka but none was given here... Please Help! Thank You
  24. AP Chem

    Write 2 complete Bronsted/Lowry acid/base reactions for the reaction between HC2c2O4- and HPO42-. Identify all conjugate pairs. my answers: HC2O4- + HPO42- -> H2C2O4 + PO43- HC2O4- and H2C2O4 are conjugate pairs HPO42- and PO43- are conjugate pairs HC2O4-
  25. English

    Each of the items below contains two of the types of verb mistakes discussed in this chapter. Find and cross out these two mistakes. Then, in the spaces provided, write the correct forms of the verbs. 1.
  26. AP Calculus Help

    The position of a particle is given by r(t)=(t+cos(t/2), -3sint). What is the particles velocity vector when t=pi? a)v= b)v= c)v= d)v= e)v= Thank you so much!!
  27. math

    solve log9(x-y)=log3(x+y
  28. Statistics and probability

    A science class has four girls and four boys in the seventh grade and three girls and five boys in the eighth grade the teacher randomly selects a seventh grader and an eighth grader from the class for competition what is the probability that the student
  29. computer

    // This program counts how many sales are made // in each of five categories of products start Declarations num category num SIZE = 5 num QUIT = 9 num sales[SIZE] = 0, 0, 0, 0, 0 string HEAD1 = "Sales" string HEAD2 = "Category Number of Sales" output
  30. Chemistry

    How many moles of Al2O3 exist in 250.0 g of sample? Please help tried still can't understand how to get it. Need before tomorrow. Thanks so much.
  31. physics

    a boy travel 5km east and then12 km south.calculate his displacement from starting point.
  32. Chem

    how did barium hydroxide appear in the absence of CO2 and how it appear in the presence of CO2
  33. Biology

    what promote cellular respiration in yeast cell? what condition appear to be detrimental to cellular respiration in yeast cell
  34. Math

    Kelly subtracted 2.3 from 20 and got 17.7. Explain why this answer is reasonable
  35. social studies

    where do people live in sw asia? Why? and what goes into choosing where you live?
  36. business math

    translate : nine times the product of three and a number
  37. Algebra 1

    A part time job pays $465.55 a week and a fixed hourly rate for any extra hours of work. For 2 weeks Emily works 4 extra hours per week and earns a total of $1211.10. What is the amount paid for each hour of extra work?
  38. Medical billing

    how do provider options impact reimbursement for patients?
  39. algebra

    : How much does it cost to make one single pizza if the average demand is 70 percent of the capacity considering that both Abbie & Melissa makes $27 an hour
  40. english

    Identify one of the darker action from "The Odyssey" poem or "Animal Farm" story. In what piece the action highlighted what intentions or emotions prompt the action? How would the story or drama change if the character involved were able to overcome the
  41. english

    Describe Odysseus as you imagined him (your interpretation) in 5-6 sentences
  42. english

    Why Odysseus is an important part of the poem? Your response should be at least 5 sentences long
  43. Chemisty

    Pouring liquid nitrogen onto a balloon decreases the volume of the balloon dramatically. Afterward, the balloon re-inflates. Use kinetic theory to explain this sequence of events. The temperature of liquid nitrogen is -196 degrees Celsius
  44. Math

    Explain how you would factor x^2-5x-24 You must explain EACH step and process t get to your factored solution The work I have done - (x-8)(x+3) I just don't understand how to explain.
  45. Math

    James has set up an ordinary annuity to save for his retirement in 19 years. If his monthly payments are $250 and the annuity has an annual interest rate of 7.5%, what will be the value of the annuity when he retires? I am studying for my math final and I
  46. Statistics

    Suppose that 4 cards are drawn from a well-shuffled deck of 52 cards. What is the probability that all 4 are hearts? Would the answer be 1/4, if I reduce it? Thanks
  47. Math

    Terrell drove at a speed of 48 1/2 miles per hour for 2 14 hours. How far did he travel?
  48. Math

    The city council gave a questionnaire to its citizens, asking them to rank their priorities for next year's budget. People were asked to rank the following four choices: (P)olice, (R)oads, (S)chools, and (T)rash removal. The results are summarized in the
  49. Math

    Four candidates running for mayor receive votes as follows: Ito: 16,032; Johnson: 36,072; Kennedy: 8,016; Lieberman: 12,024 How do I find the majority, if there is one? Thanks?
  50. Chemistry

    After the initial 1 mL of 0.2 M FeCl3 (aq) and 1 mL of 0.2 M KSCN (aq) were combined it was then diluted with an additional 130 mL of deionized water. Which way would this dilution cause the equilibrium to shift? Is a dilution going to be a stress in all
  51. Politics

    what is it that makes a state a capitalist state? Could be the way it influences the world in economic ways? If so, what else would cause a state to become capitalist? Thanks!
  52. Chemistry

    A 0.75 g sample of X2CO3 is dissolved in water and 80 mL of 0.20 M CaCl2 solution is added. This is the balanced equation I have created. X2CO3(aq) + CaCl2(aq) → CaCO3(s) + 2 XCl(aq) Based on the ratio in your balanced equation, how many moles of X2CO3
  53. English

    The crowd encouraged the team. The team scored 10 points. a-the crowd encouraged the team to score 10 points. b-When the crowd encouraged the team, the team scored 10 points. c-The crowd encouraged the team, the team scored 10 points. d-The team,encouraged
  54. Algebra

    An ant is roughly 10^(-3) meters in length and the average human roughly one meter. How many times longer is a human than an ant? The human is ____ times longer than an ant.
  55. Math

    Ryan needs 8 5/16 feet of molding to finish a closet. He has 6 feet of molding. How many more feet of molding does he need?
  56. Math

    Which is a reasonable estimate? 2/3 + 4/5 a.
  57. Math

    In a book closet, mathematics books are kept in stacks of 4. If each student carries no more than one stack, what is the least number of students needed to carry books for a class of 23? Your multiple choices are a. 5 students b. 6 students c. 27 students
  58. Math

    In a book closet, mathematics books are kept in stacks of 4. If each student carries no more than one stack, what is the least number of students needed to carry books for a class of 23?
  59. Chemistry

    You are supposed to mix 250 mL of a 0.1 M solution of Pb(NO3)2 solution. You would need to mix ______ g of Pb(NO3)2 with enough water to make 250 mL of solution.
  60. Algebra

    If Adam is 30 years older than Alyssa and the sum of their ages is 36. How old are they?
  61. Algebra

    A load of 12 kg stretches 15 cm and a load of 30 kg stretches 18 cm. Find the natural (unstretched) length of the spring.
  62. math

    kelly spend 2/3 of her money on books and from the remaining money, kelly spent 1/4 on food how much money did kelly spend on food from here total amount of money?
  63. Math

    Hi can someone please help me? A recent study gave the information shown in the table about ages of children receiving toys. The percentages represent all toys sold. Age (years) Percentage of Toys 2 and under 3-5 6-9 10-12 13 and over 17% 19% 24% 13% 27%
  64. math

    24 equal squares. what is side length of one square.
  65. Are All Right? Math

    Use cross products to see if each pair of ratios forms a proportion. Replace each box with = or ≠. 1. 7/5 ? 15/10 = ≠
  66. Math

    Find the unit rate. Round to the nearest tenth, if necessary. 344 miles in 11 hours 344 3,784 0.03 31.27 ** Find the unit rate. In 10 months, 62.6 gallons were used. 0.16 10 6.26 ** 626
  67. Math

    An angle θ satisfies the relation csc θ cos θ = -1. A) Use the definition of the reciprocal trigonometric ratios to express the left side in terms of sin θ and cos θ. B) What is the relation between sin θ and cos θ for this angle? C) Determine two
  68. Chemistry

    If you used 50 grams of copper (II) oxide, how much copper would be produced. (Use the ratio)
  69. Calculus

    Use a(t) = -32 ft/sec2 as the acceleration due to gravity. (Neglect air resistance.) A ball is thrown vertically upward from a height of 6 feet with an initial velocity of 68 feet per second. How high will the ball go?
  70. Calc

    The maker of an automobile advertises that it takes 13 seconds to accelerate from 25 kilometers per hour to 90 kilometers per hour. Assuming constant acceleration, compute the following. The acceleration in m/s^2 The distance the car travels during the 13
  71. Calc

    Use upper and lower sums to approximate the area of the region using the given number of subintervals (of equal width). (Round your answers to three decimal places.) y = 5/x
  72. Math (Grade 11)

    1) The measurement is 15.5, the tolerance is 5. Whats the precision, uncertainty, range, nominal value and precent error? 2) The measurement is 14.5, the tolerance is 6. Whats the precision, uncertainty, range, nominal value and percent error? 3) The
  73. MATH

    What is the estimated perimeter of an ellipse if the major axis has a length of 15 ft and the minor axis has a length of 7.5 ft?
  74. math

    For his exercise today, Josh plans to both run and swim. Let r be the number of laps he runs and let s be the number of laps he swims. Each lap he runs takes him 4 minutes, and each lap he swims takes him 3 minutes. He wants to exercise for at least 30
  75. chemestry

    the Earth has mass of approximately 5.98* 10^24kg and radius 6.38* 10^6m. what is the density of the Earth in (a)g/cm^3 and (b) kg/m^3 ?
  76. Chemistry

    Write chemical formulas for the compounds formed by the following positive and negative ions: Ba2+ and NO3-, Al3+ and Co3, and K+ and PO43-
  77. Chemistry

    If you start with 4.00 moles of C3H8 (propane) and 4.00 moles of O2, how many moles of carbon dioxide can be produced?
  78. Chemistry

    A glass of water contains 1.2 x 1024 molecules of water. An additional 4.0 moles of water are poured into the glass. How many moles of water are in the glass?
  79. Chemistry

    In the reaction C + O2 → CO2, 18 g of carbon react with oxygen to produce 72 g of carbon dioxide. What mass of oxygen would be needed in the reaction?
  80. Chemistry

    The Ka of an acid is 1.3 x 10–7. Based on the Ka and its relationship with Kw, what is the value of Kb?
  81. math

    How many 1oz bottles will this solution fill.
  82. College Algebra math

    A plane flies due east for 35 miles and then due south until it is 37 miles from its starting point. How far south did the plane fly?
  83. Chemistry

    Ammonia gas is passed into water, yielding a solution of density of 0.93 g/mL and containing 18.6% NH3 by weight. What is the mass of NH3 per mL of solution.
  84. Chemistry

    A sample of impure Limestone weighing 0.3440 g was treated with 50 mL of HCl 0.1363 mol/l. after elimination of all CO2 by boiling, excess acid was created by 4.45 mL of NaOH 0.1445 mol/L1. Calculate the% (w/w) of CaO and CaCO3 in the sample
  85. math

    What is the 20th term of the sequence that begins with −2, 4, -8, 16 ANSWER CHOICES: A)2,097,152 B)524,288 C)-524,288 D)1,048,576
  86. Geography -Yr10

    Q: List the impacts of reduced river flows that were identified within the Murray-Darling Basin in the 1980s. . Thanks
  87. Geography -Yr10

    Outline the reasons for competition over the Murray River's water resources in the late nineteenth century. I found nothing online for this question?
  88. Geography - Yr10

    In what ways is the Local Council involved in land management? What are they mainly responsible for?
  89. Chemistry

    Knowing that the milk of magnesia contains 8 g% of Mg (OH)2, using 1 g of milk of magnesia and added 50 mL of 0.100 M HCl, determine the required volume of a solution of 0.105 M NaOH to titrate the excess HCl 0.100 M.
  90. Math

    by completing the​ square, what value should you add to each side of the​ equation? x^2- 7x=5
  91. MATH

    If you roll a 6 sided dice 6 times, what is the best prediction possible for the number of times you will roll a two? A) 6 B) 1 C) 2 D) 0
  92. Chemistry

    Which pair of compounds will form a solution?Benzene (C6H6) and hexane (C6H14)Na2SO4 and benzene (C6H6)NaCl and hexane (C6H14)H2O and CCl4More than one of the combinations above will form solutions.

    Mars rotates slowly about its axis, the period being 687 days. The mass of mars is 6.39 x 10^23 kg. Determine the radius for a synchronous satellite in orbit around Mars. (assume circular orbit)
  94. Chemistry

    If it takes 45 days for 80.0 mg of a particular radioactive isotope to decay to 10.0 mg what is its half-life?
  95. Chemistry

    Calculate the concentrations of Cd ⁺ ², [Cd (CN)₄-²] and CN at equilibrium when they dissolve mole of 0.42 Cd (in the ₃)²⁺ 2.50 M. Given: Kf = 7, 1 x 10 ^16
  96. Chemistry

    What is the pH of a solution made by mixing 1.40 mL of 0.0043 molar Sr(OH)2 with 8.90 mL of 0.0029 molar Sr(OH)2 solution?
  97. math

    peggy was taking a timed 90 question test she was able to correct 90% of the questions how many questions did she answer correctly
  98. Chemistry

    Consider the chemical equation. 2H2 + O2 -> 2H2O What is the percent yield of H2O if 87.0 g of H2O is produced by combining 95.0 g of O2 and 11.0 g of H2? a 56.5% b 59.0% c 88.5% d 99.7%
  99. Business

    A department manager is attempting to motivate employees by moving them from one job to another. What is this strategy called? A. Job enlargement C. Job rotation B. Job enrichment D. Job justification
  100. Physics

    A 4kg box is attached to a 2.4m rope rotating on platform. Max tension can withstand without breaking is 140N. 1.) Find Max. speed w/ which the box can rotate if the surface of platform is frictionless. 2.) Find Max speed w/ which box can rotate if Coeff.


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