Questions Asked in August 2010

Most Popular Questions of August 2010

  1. english

    this check my answer Words: Deterrent, implication, inequity, infirmity, infringe, innovation, revitalize, sparse, subjective, succinct, 1- 2 When the candidate for mayor saw the sparse turnout for his speech, he knew he had to do something to revitalize

    asked by jae on August 30, 2010
  2. The elements and Principles of Design

    CAN SOMEONE PLEASE CHECK MY ANSWERS. (MY ANSWERS ARE AT THE BOTTOM...) 1. Which one of the following factors is one of the principles of design? A. Form C. Pattern B. Color D. Balance 2. Of the following expressions, which best describes the concept of

    asked by Anonymous on August 19, 2010
  3. please check

    As Alex sat down in the carnival tent, the lights dimmed. A spotlight revealed a short, heavy man holding a thick chain. He tugged the chain, and an old, muzzled bear appeared. The man, the animal's owner, announced that the bear's name was Sally. He said

    asked by jae on August 30, 2010
  4. english please check

    Answer 1.Elicit 2.Engross 3.obsolete 4.Terminate 5.Tangible 6.Acclaim 7.Exploit 8.Escalate 9.Methodical 10. Adjacent 1-2 The gifted ice skater's routine _(e)d the audience . It was the epitome grace and power combined. At the end, a long, rapid spin _(e) d

    asked by jae on August 30, 2010
  5. AP Physics

    mgh=1/2mv^2, solve for the variable v

    asked by Lisa on August 1, 2010
  6. Physical Education

    Two bodies are thrown vertically upwards with the same initially velocity of 98metre/sec but 4 sec apart.How long after is thrown will they meet?

    asked by Chris on August 25, 2010
  7. Chemistry

    NaN3 is used in some automobile air bags. The impact of a collision triggers the decomposition of NaN3 as follows: 2NaN3(s) to 2Na(s) + 3N2(g). The nitrogen gas produced quickly inflates the air bag between the driver and the windshield. Calculate the

    asked by HaldriecH on August 6, 2010
  8. chemistry

    2H2O2 --- 2H2O + O2 is this a redox reaction if so what is the oxidized reactant and reduced reactant

    asked by Kelsey on August 26, 2010
  9. Chemistry

    How much heat (in kJ) is evolved in converting 1.00 mol of steam at 145.0 degrees C to ice at -45.0 degrees C? The heat capacity of steam is 2.01 J/g* degrees C and of ice is 2.09 J/g*degrees C .

    asked by jay on August 4, 2010
  10. Chemistry

    If BaCO3 is placed in an evacuated flask, what partial pressure of CO2 will be present when the reaction reaches equilibrium? 298K BaCO3(s)-->BaO(s)+CO2(g)

    asked by Ally on August 2, 2010
  11. english

    Which group of words is the sentence below misplaced? Having been discovered, Fifi looked up at his owner with puppy-dog eyes. a)with puppy-dog eyes b)been discovered c)his owner d)Fifi looked up

    asked by nancy on August 4, 2010
  12. Chemistry

    A mixture of methane (CH4) and ethane (C2H6) of mass 13.43g is completely burned in oxygen. If the total mass of CO2 and H2O produced is 64.84 g, calculate the fraction of CH4 in the mixture. CH4 + C2H6 arrow CO2 + H2O 13.43g 64.84g Would I do

    asked by Amy~ on August 27, 2010
  13. math

    Carlos Martin received a statement from his bank showing a balance of $56.75 as of March 15th. His checkbook shows a balance of $87.37 as of March 20. The bank returned all cancelled checks but two. One check was for $5.00 and the other was for $13.25. How

    asked by mary on August 10, 2010
  14. Physics

    A sprinter explodes out of the starting block with an acceleration of +2.3 m/s^2, which she sustains for 1.2 s. Then, her acceleration drops to zero for the rest of the race. What is her velocity (a) at t=1.2 s ans (b) at the end of the race?

    asked by Heather on August 29, 2010
  15. inorganic chemistry

    what dominant colour appears for(a)the mecury street bulb (b)the sodium street lamp and (c) an incandescent bulb?

    asked by kabelo on August 30, 2010
  16. Physics

    You are trying to overhear a juicy conversation, but from your distance of 15.0m, it sounds like only an average whisper of 25.0 dB. So you decide to move closer to give the conversation a sound level of 70.0 dB instead.How close should you come.

    asked by Veronica on August 15, 2010
  17. math

    The base of a rectangle is 2cm greater than its height. Find the base and the height of the parallelogram if the area of the parallelogram is 120 cm2. Can this be shown as a quadratic and factored?

    asked by MARIANNE on August 28, 2010
  18. Chemistry

    A solid white substance A is heated strongly in the absence of air. It decomposes to form a new white substance B and a gas C. The gas has exactly the same properties as the product obtained when carbon is burned in an excess of oxygen. Based on these

    asked by Ana on August 29, 2010
  19. chemistry

    A block of metal has a width of 3.2 cm, a length of 17.1 cm, and height of 3.7 cm. Its mass is 1.3 kg. Calculate the density of the metal.

    asked by Mely on August 27, 2010
  20. physics

    A 0.060 kg tennis ball, moving with a speed 2.50 m/s, collides head on with a 0.090kg ball initially moving away from it at a speed of 1.15 m/s. Assuming a perfectly elastic collision, what are the speed and direction of each ball after the collision?

    asked by joy on August 19, 2010
  21. statistics

    It is thought that prehistoric Indians did not take their best tools, pottery, and household items when they visited higher elevations for their summer camps. It is hypothesized that archaeological sites tend to lose their cultural identity and specific

    asked by sharon on August 22, 2010
  22. Math

    A pair of fair dice is rolled. Let E denote the event that the number landing uppermost on the first die is a 3, and let F denote the event that the sum of the numbers landing uppermost is 6. Determine whether E and F are independent events

    asked by Jack on August 15, 2010
  23. Math - Pre-Algebra

    A set of building blocks of various shapes and colors. If 30% of the blocks are cubes, and 40% of the cube blocks are red the then _______? what % of the blocks are red cubes.

    asked by BC on August 29, 2010
  24. Physics

    One cubic meter (1.00 m^3) of aluminum has a mass of 2.70 multiplied by 10^3 kg, and the same volume of iron has a mass of 7.86 multiplied by 10^3 kg. Find the radius of a solid aluminum sphere that will balance a solid iron sphere of radius 1.40 cm on an

    asked by Z32 on August 27, 2010
  25. science

    NH2-, NH3, and NH4+ have H-N-H bond angles of 105, 107 and 109. Explain this variation in bond angles.

    asked by Joseph on August 10, 2010
  26. chemistry

    what mass of solid AgBr is produced when 100.0 mL of 0.150 M AgNO3 is added to 20.0mL of 1.00 MNaBr? i keep getting the answer 3.75 g however when i checked in the back of the book it gives me 2.82 g.. can you please explain the universal steps for me

    asked by Crickett on August 23, 2010
  27. Physics

    I need help solving this please! I think that for part (b) I can use energy and wavelength to solve for frequency and the one with the highest frequency is the most damaging, but I'm not sure what to do for part (a). You want to study a biological specimen

    asked by Brianna on August 15, 2010
  28. Chemistry

    Ca3(PO4)2 + 3 H2SO4 -> 3 CaSO4 + 2 H3PO4 What masses of calcium sulfate and phosphoric acid can be produced from the reaction of 1.0 kg calcium phosphate with 1.0 kg concentrated sulfuric acid (98% H2SO4 by mass)?

    asked by Anonymous on August 16, 2010
  29. Math

    Determine the equation of the parabola with roots 2+sqrt(3) and 2-sqrt(3), and passing through the point (2,5).

    asked by Emily on August 23, 2010
  30. english check answer

    1) wary 2) inclination 3) dilemma 4) Sabotage 5) Retort 6) zeal 7) 8) demoralize 9) Irrate 10) Subsequent words Curt, Demoralize, dilemma,inclination, irate, retort, sabotage, subsequent, wary,zeal if my carpets need cleaning or i want a new cellphone

    asked by jay on August 28, 2010
  31. chemistry

    how would you prepare 1.00 L of 0.50 M solution of NiCl2 from the salt nicl2·6H2O? thanks :)

    asked by kelly on August 24, 2010
  32. health

    Which of the following is true in regard to limited data sets? A.Patients must authorize the use of limited data sets. B. Those who receive limited data sets can pass them on witout restrictions. C. Limited data sets cant include a patiemts city, state,

    asked by janice on August 30, 2010
  33. algebra1

    why doews oshgosh jog around the high schooll track 98 times every day

    asked by mrs.austin on August 22, 2010
  34. Chemistry

    Does anyone know why Glucose is soluble in water but is not soluble in Hexane?

    asked by Bobby on August 9, 2010
  35. Precalculus

    If c= 16 and B= 67 degrees, find a.

    asked by Danielle on August 17, 2010
  36. english vocab

    __________ 1-2 Already angry,the customer became more ___ when he __________ received only this __ response: No return. _______ 3-4 when I answer my phone and hear someone demand, "who is this?" _______ my _ is _ to "I'm the person whose phone was ringing.

    asked by jay on August 28, 2010
  37. Chemistry

    What would be the steps to solving this problem? The aluminum sulfate hydrate [Al2(SO4)3 (times) xH2O] contains 8.20 % Al by mass. Calculate x, that is , the number of water molecules associated with each Al2(SO4)3 unit.

    asked by Amy~ on August 26, 2010
  38. Chemistry

    Any help would be great on the below problems. I am not sure where to begin. How do I solve these? Do I use a formula? 1. You are asked to make 500.0 mL of a 4.5M solution of HCl, but the only HCl you have available to dilute is 18.0M. Describe how you

    asked by Ashley on August 17, 2010
  39. statistic

    A lottery ticket has a grand prize of $28 million. The probability of winning the grand prize is .000000023. Based on the expected value of the lottery ticket, would you pay $1 for a ticket? Show your calculations and reasoning clearly.

    asked by Kim on August 27, 2010
  40. statistics

    In a contest in which 8 contestants are entered, in how many ways can the 5 distinct prizes be awarded?

    asked by Tim on August 8, 2010
  41. college physics

    A 0.25 kg skeet (clay target) is fired at an angle of 30 degrees to the horizon with a speed of 25 m/s. When it reaches the maximum height, it is hit from below by a 15 g pellet travelling upward at a speed of 200 m/s. The pellet is embedded in the skeet.

    asked by jen on August 19, 2010
  42. Algebra ...Please check this to see if I am corect

    For the following equation, state the value of the discriminant and then describe the nature of the solutions. 6x^2-3x+2=0 I came up with the value of the discriminant as 35. Then I came up with it has two real solutions. Is this correct?

    asked by MBK on August 25, 2010
  43. trig

    find exact value of cos(23pi/6)

    asked by shaili on August 9, 2010
  44. chemistry

    I need an equation for the neutralization of lemon juice (citric acid) with baking soda (sodium hydrogen or sodium bicarbonate) that shows a proton transfer to form carbonic acid and a salt..And an equation for the decomposition of carbonic acid to water

    asked by Norma on August 4, 2010
  45. trigo

    A submarine at the surface of the ocean makes an emergency dive, its path making an angle of 21deg with the surface. a. If it goes for 300 meters along its download path, how deep will it be? What horizontal distance is it from its starting point? b. How

    asked by trigofunctions on August 3, 2010
  46. chemistry

    I have posted this once and still cannot get the correct answer. Determine the mass of carbon monoxide that is produced when 45.6 of methane, CH4, react with 73.2 g of oxygen , O2. The products are carbon monoxide and water vapour.

    asked by Kelsey on August 3, 2010
  47. Calculus disaster

    Uranium ore has two main isotopes, mostly U-238 with just a trace amount of U-235. In a sample of Uranium ore, 99.85% of the atoms are U-238 atoms and 0.15% are U-235 atoms. Before the Uranium can be used in a nuclear power plant, the proportion of U-235

    asked by Amanda on August 28, 2010
  48. college physics

    Each of four particles moves along an x-axis. Their coordinates (in meters) as functions of time (in seconds) are given by: Particle #1: x(t)=2t^2-4 Particle #2: x(t)= -3t-4 Particle #3: -2t^2-4 Particle #4: 2 *[sq. root (t+1)] -4 Which of these particles

    asked by Thomas on August 24, 2010
  49. Chemistry

    For many years the recovery of gold-that is, the seperation of gold from other materials-involved the use of potassium cyanide: 4AU + 8KCN + 02 +2H20 -> 4KAu(CN)2 + 4KOH What is the minimum amount of KCN in moles needed to extract 29.0 g (about an ounce)

    asked by Kate on August 2, 2010
  50. college physical science

    According to table 1.3, what volume of iron would be needed to balance a 1.00cm3 sample of lead on a two pan laboratory balance? Table 1.3 shows densities g/cm3 such as iron=7.87g/cm3 and lead is 11.4g/cm3

    asked by Richard on August 29, 2010
  51. physics

    A spring with k = 53 N/m hangs vertically next to the 15 cm mark on the ruler. If a 2.5 kg mass is now attached to the end of the spring, where will the end of the spring line up with the ruler marks

    asked by kathy on August 19, 2010
  52. Math

    Question: A tunnel with a parabolic arch is 12 m wide. If the height of the arch 4 m from the left edge is 6 m, can a truck that is 5 m tall and 3.5 m wide pass through the tunnel? Justify your decision. I drew the graph of the arch with x-intercepts (0,0)

    asked by Emily on August 19, 2010
  53. Chemistry

    Lysine, an essential amino acid in the human body, contains C,H,O, and N. In one experiment, the complete combustion of 2.175g of lysine gave 3.94g CO2 and 1.89g H2O. In a separate experiment, 1.873 g of lysine gave 0.436 g NH3. (a) Calculate the empirical

    asked by Amy~ on August 27, 2010
  54. hca 220

    hca 220 hca 220 Use 10 medical words discussed in this week’s reading to create a script of dialogue between two medical professionals.

    asked by Anonymous on August 16, 2010
  55. Chemistry

    Many homes in rural America are heated by propane gas, a compound that contains only carbon and hydrogen. Complete combustion of of a sample of propane produced 2.641 grams of carbon dioxide and 1.422 grams of water as the only products. Find the empirical

    asked by Anonymous on August 16, 2010
  56. chemisry

    Cd/Cd2+//H+/H2/Pt Write the oxidation and reductionhalf reactions. Sketch a possible deisgn cell. I am unclear on the Pt portion and the charges ?

    asked by Kelsey on August 30, 2010
  57. AP Chemistry

    which of the following is the most polar? 1. I3- 2. XeF2 3. SCN- 4. O3 5. N2O i know it's not I3- or SCN-. which one would it be.

    asked by Nicole on August 8, 2010
  58. Chermistry

    if molar enthalpy of vaporization of enthanol is 38.6 kJ/mol, how many moles of ethanol are vaporize when required heat is 200.72kJ

    asked by Paris on August 31, 2010
  59. U.S government

    Which statement best expresses the meaning of the opening words of the U.S. Constitution, "We, the people..."? A. sovereignty is derived from the consent of the governed B. all citizens are guaranteed freedom of speech C. federal laws are subject to

    asked by jenny on August 11, 2010
  60. Chemistry

    1. A sample of argon gas is at a pressure of 1.24 x 10^4 kPa and a temperature of 24°C in a rigid 25-L tank. How many moles of argon does this tank contain? I ended up with .130 but its 130 Can someone tell me what I did wrong? This whole chapter on gases

    asked by Anonymous on August 11, 2010
  61. algebra2

    what do you call it when someone pays back a loan quickly??

    asked by sally on August 29, 2010
  62. chemistry

    How much ice (in grams) would have to melt to lower the temperature of 350 of water from 24 to 4? (Assume the density of water is 1.0 .)

    asked by sara on August 27, 2010
  63. physis

    The range of human hearing is roughly from twenty hertz to twenty kilohertz. Based on these limits and a value of 343 m/s for the speed of sound, what are the lengths of the longest and shortest pipes (open at both ends and producing sound at their

    asked by Anonymous on August 7, 2010
  64. chemistry

    6.00g of gold was heated from 20.0 degrees celcius to 22.0 degrees celcius. how much heat was applied to the gold?

    asked by sharnice on August 14, 2010
  65. physics

    The disk shaped head of a pin is 1.0 mm in diameter. Which of the following is the best estimate of the number of atoms in the layer of atoms on the top of the surface of the pinhead? 1. 10 to the 34th power 2. 10 to the 19th power 3. 10 to the 24th power

    asked by Kailey on August 26, 2010
  66. Chemistry

    A gaseous mixture containing 4.15 mol of hydrogen gas and 7.13 mol of oxygen gas reacts to form steam (a) Write the balanced equation for the reaction. (b) What is the limiting reactant? (c) What is the theoretical yiels of steam in moles? (d) How many

    asked by Jao on August 22, 2010
  67. Chemistry

    The steps to getting the answer. A certain metal oxide has the formula MO where M denotes the metal. A 39.46g sample of the compound is strongly heated in an atmosphere of hydrogen to remove oxygen as water molecules. At the end, 31.70g of the metal is

    asked by Amy~ on August 26, 2010
  68. trigonometry

    From a mountain 1780 ft. high, the angle of depression of a point on the nearer shore of a river is 48deg40mins and of point directly across on the opposite side is 22deg20mins. What is the width of the river between the two points?

    asked by Winsel on August 10, 2010
  69. PreCalc

    The area of a parking lot is 805 square meters. A car requires 5 square meters and a bus requires 32 square meters of space. At most 80 vehicles can park at one time. If the cost to park a car is $2.00 and the cost to park a bus is $6.00, how many buses

    asked by Anonymous on August 31, 2010
  70. Chemistry

    Wh does the blue color of Iodine disapear when amylose reacts with saliva? I had thought it was because Amylase in saliva will replace the I2 in the amylose coil and thus removes the color, but I got it wrong. I know it has to be connected to the Amylase

    asked by Bobby on August 8, 2010
  71. Finance

    Medallion Cooling Systems, Inc., has total assets of $10,000,000, EBIT of $2,000,000, and preferred dividends of $200,000 and is taxed at a rate of 40%. In an effort to determine the optimal capital structure, the firm has assembled data on the cost of

    asked by Lillian on August 9, 2010
  72. math

    Four blue socks, four white socks, and four gray socks are mixed in a drawer. You pull out two socks, one at a time, without looking. a. Draw a tree diagram along with the possible outcomes and the probabilities of each branch. b. What is the probability

    asked by kirk on August 15, 2010
  73. managerial

    The demand curve for haircuts at Terry Bernard's Hair Design is P=20-0.20Q where Q is the number of cuts per week and P is the price of a haircut. Terry is condering raising her price above the current price of $15. Terry is unwilling to raise price if the

    asked by tina on August 8, 2010
  74. Chemistry

    If 5.0 moles of propane react, how many molecules of water will be formed? A.3.0x10.24 B.4.8x10.24 c.1.2x10.25

    asked by Jarred on August 5, 2010
  75. Statistics

    Calculate each binomial probability: a. Fewer than 4 successes in 12 trials with a 10 percent chance of success. b. At least 3 successes in 7 trials with a 40 percent chance of success. c. At most 9 successes in 14 trials with a 60 percent chance of

    asked by Patrick on August 29, 2010
  76. English

    I need help to error free assignment. Sappho born 630 B.C. in Lesbo. She was lyric poet. She wrote poetry that was admired by ancient world. Her poetry work was very personal in nature .She talk about herself, family , daughter and lovers. She also

    asked by hiba on August 26, 2010
  77. trigo

    A space shuttle pilot flying toward the Suez Canal finds that the angle of depression on one end of the canal is 38.25deg and the angle of depression to the other end is 52.75deg. If the canal is 100.6 mi long, find the altitude of the space shuttle.

    asked by trigofunctions on August 3, 2010
  78. Chemistry

    How many liters of gasesous methane (CH4) must be burned in oxygen to produce enough H2O and CO2 to fill a 3.0 L balloon? Assume that H2O and CO2 are the only combustion products and that the temperature and pressure remain constant. How would I solve

    asked by Amy~ on August 29, 2010
  79. trig

    A missile is fired at an angle of 85 from the horizontal. At one point, its speed was 1,000 mph. Find its horizontal velocity in miles per minute

    asked by buho on August 4, 2010
  80. physics

    [20 pts] A 2.00 kg block is pushed against a spring with negligible mass and force constant k = 400 N/m, compressing it 0.220 m. When the block is released, it moves along a frictionless, horizontal surface and then up a frictionless incline with slope 37

    asked by joy on August 19, 2010
  81. Chemistry

    2 SO2 + O2 --> 2 SO3 What happens to the total volume when 3L of SO2 react with 2L of O2 to form the max. amount of SO3 possible?

    asked by Renate on August 18, 2010
  82. Math

    The revenue function for a production by a theater group is R(t)= -50t^2+300t, where t is the ticket price in dollars. The cost function for the production is C(t)= 600-50t. Determine the ticket price that will allow the production to break even.

    asked by Carie on August 20, 2010
  83. chem

    i need to balance this redox euation Mn+2 +H2O2----- MnO2 + H2O

    asked by Lawryn on August 4, 2010
  84. health care

    you are a manager of a variable hospital department and you just received your monthly budget results that state that your salaries were higher and your supplies were lower than budgeted. Explain what factors you should consider when writing your variance

    asked by betty on August 20, 2010
  85. College Chemistry

    Complete the following table for aqueous solutions of caffeine, C8H10O2N4. Find: Molality Mass Percent Solvent Ppm Solute Given: Mole Fraction Solvent = 0.900 Molar Mass is 194.2g i believe.

    asked by James on August 30, 2010
  86. Physics

    We can reasonably model a 75 W incandescent light bulb as a sphere 6.0 cm in diameter. Typically, only about 5% of the energy goes to visible light; the rest goes largely to non-visible light infrared radiation. (a) What is the visible light intensity (in

    asked by Brittany on August 11, 2010
  87. phys102

    a copper wire has a diameter of 1.02mm,the wire carries a constant current of 1.67A,the density of the free electrons is 8.5X10^28 e/m^3.calculate the current density and drift velocity

    asked by kabelo on August 14, 2010
  88. physics

    A person walks first at a constant speed of 4.90 m/s along a straight line from point A to point B and then back along the line from B to A at a constant speed of 2.70 m/s. (a) What is her average speed over the entire trip?

    asked by mattie on August 31, 2010
  89. statistics

    Use the random-number table to simulate the outcomes of tossing a quarter 25 times. Assume that the quarter is balanced (i.e., fair). (Start at row 1, and let 0, 1, 2, 3, 4 indicate heads and 5, 6, 7, 8, 9 indicate tails. Enter H for heads and T for tails,

    asked by Christina on August 24, 2010
  90. algebra1

    an internet serive provider charges $9.95/month for the first 20 hours and $0.50 for each additonal hour. write and expression presenting the charges for h hours of use in one month h is more than 20 hours. what is the charge for 35 hours... pls show me

    asked by alanaR. on August 26, 2010
  91. Math

    You need to replace the molding around a floor that is 15 ft. long & 23 ft. 6 in. wide. The molding sells for $0.50 per ft.. How much will the molding cost?

    asked by J on August 18, 2010
  92. college chemistry

    When solutions of AgNO3 and NaOH react, the balanced molecular equation is 2AgNO3(aq) + 2NaOH(aq) Ag2O(s) + 2NaNO3(aq) + H2O(l) How much Ag2O is produced when 0.200 g of AgNO3 and 0.200 g of NaOH react?

    asked by michelle on August 7, 2010
  93. Chemistry

    find the pH of each of the following solutions of mixtures of acids: .125M in HBr and .130 M in HCHO2, .155M in HNO2 and 9.0*10^-2M in HNO3, 5.5×10−2 in acetic acid and 5.5×10−2 in hydrocyanic acid

    asked by Kristen on August 2, 2010

    1. You have 88.8 mL of 2.50 M solution of Na2CrO4 (aq). You have 125 mL of a 2.50 M solution of AgNO3 (aq). Calculate the concetration of Na+ when the two solutions are added together. 2. You have 75.0 mL of 2.50 M solution of Na2CrO4 (aq). You have 125 mL

    asked by Alex on August 30, 2010
  95. physics

    A 1000 kg boat is traveling at 90 km/h when its engine is shut off. The magnitude of the kinetic frictional force f_k between the boat and water is proportional to the speed v of the boat: f_k = 70v, where v is in meters per second and f_k is in newtons.

    asked by Kelsey on August 30, 2010
  96. statistics

    Given the following scatter diagram , the sample correlation coefficient r: Has a positive linear correlation Has a negative linear correlation. Has little or no correlation. Looks close to + 1.00

    asked by Karen on August 19, 2010
  97. math

    On a certain exam, Tony corrected 10 papers and found the mean for his group to be 70. Alice corrected the remaining 20 papers and found that the mean for her group was 80. What is the mean of the combined group of 30 students?

    asked by kirk on August 12, 2010
  98. science

    NH2-,NH3, and NH4+ have H-N-H bond angles of 105, 107, and 109. Explain this variation in bond angles

    asked by Joseph on August 12, 2010
  99. chemistry

    how would you prepare 1.00 L of a .50M solution of H2SO4 from concentrated (18M) sulfric acid?

    asked by kelly on August 24, 2010
  100. science

    Geologists have divided the history of the earth into four different eras. Which era below is not one of the four? a) Mesozoic Era b) Cenozoic Era c) Precambrian Era d) Stone Era e) Paleozoic Era Just need to know if my answer or right or wrong. Thanks! :)

    asked by ant on August 19, 2010