1. CHemistry

    I did a project for lab chemistry where my aim was to see which substance, from a selection of 4 chlorides, recrystallises from a solution to form the most crystals. The 4 chlorides were KCl, NaCl, MgCl2 and CaCl2. KCl and NaCl didn't form any crystals,
  2. Chemistry

    I did a project for lab chemistry where my aim was to see which substance, from a selection of 4 chlorides, recrystallises from a solution to form the most crystals. The 4 chlorides were KCl, NaCl, MgCl2 and CaCl2. KCl and NaCl didn't form any crystals,
  3. Chem

    A carless chemistry student pours 200 grams of methanol, a flammable substance into the sink. Another careless chemistry student causes the bad situation to get even worse by dropping a lit match into the sink. The metanol burns completely with 300 grams
  4. Chemistry

    What are the changes associated with a chemical reaction?
  5. science

    what is an example of a chemical reaction.
  6. CHMISTRY

    HOW DO YOU CALCULAT KC FOR THE REACTION
  7. Chemistry

    Does Pb(NO3)2 + Cu has a reaction? if so, what will it be?
  8. CHEMISTRY

    What is reaction between HI+HNO3
  9. chemistry

    The nuclear reaction Sn ¨ Sb + ? is an example of
  10. Chemistry

    E(V) for half reaction 3N(-1/3) -> 3 N(0) + e-
  11. chemistry

    if [NO]=2M , [N2] = 1M, and [O2]= 1M, is the reaction at equilibrium?
  12. chemistry

    how do you find the Kc of a reaction?
  13. Biochem

    You wish to measure the ∆G°' for the hydrolysis of ATP: ATP --->ADP + Pi But the equilibrium for the hydrolysis lies so far toward products that analysis of the ATP concentration at equilibrium is neither practical or accurate. However, you have
  14. Corrected Temperature Problem

    Q: The activation energy of a certain reaction is 32.9 kJ/mol At 25 degrees C the rate constant is 0.0160 units s-1 units. At what temperature in degrees Celsius would this reaction go twice as fast? My work: ln(0.0160/0.032) = (32,900/8.314)(1/T2 -
  15. science

    I need a little assistance. Can you help? The question which seems to be simple enough is What is a physical change? My son answered - A physical change is any change that alters the form or appearance of matter into a different substance. I do not agree.
  16. biology

    I have some questions that relate to table 2.1 which lists the chemical elements that occur naturally in the human body. Similar percentages of these elements are found in most living organisms. a. In what abiotic (non-life) chemical forms are these
  17. 7th grade science Ms. Sue please help if you can

    1. Violent storms generally form along _____. (1 point) occluded fronts cold fronts warm fronts stationary fronts 2. Areas of low pressure usually have _____. (1 point) cloudy weather good weather descending air none of the above 5. Tornadoes can form when
  18. English

    1.Susan made small and cute teddy bears. (In this sentence, what is the meaning of 'teddy'?) 2. I like both Tom and Don. 2-1. I like Tom and Don. 2-2. I want to marry Tom or Don. 2-3. I like neither Tom nor Don. 2-4. I don't like Tom, and I don't like Don,
  19. Chem

    If the initial pressure of HD(g) is 8.913 atm, calculate the % decomposition of HD(g) when the reaction comes to equilibrium according to the balanced equation. The value of Kp at 1000 K is 0.26. The initial pressure of the reaction products is 0 atm.
  20. CHEMISTRY

    The equilibrium constant for the reaction, SO2(g)+ NO2(g) <----> NO(g)+ SO3(g) has been experimentally determined as a function of temperature. The results are presented in the table below. T (°F) KC 285 662 752 156 842 93.4 932 59.6 1022 40.2 If
  21. Chemistry Lab

    So I did a kinetics lab on the rate of reaction of peroxydisulfate ion with iodide ion. Part 1 was the effect of concentration. One of the questions asked is to calculate the amount of thiosulfate consumed in moles. My results for trial 1 were (Times taken
  22. English

    Posted by rfvv on Monday, October 4, 2010 at 2:24am. 1. Cut long rice cake into 4-5 cm pieces. (How do you read '4-5 cm'?) 1-1. four to five centimeter 1-2. four and five centimeter 1-3 four or five centimeter 1-4 from four to five centimeter (Which one is
  23. science

    Which rate constant would result in the fastest reaction? Which rate constant would result in the fastest reaction? 1 1.3 × 103 L/mol · s 2 2.8 L/mol · s 3 9.5 × 10-2 L/mol · s 4 4.2 × 10-3 L/mol · s
  24. Chemistry

    Just some homework. Would like to know if I am right, thanks. 1. Adding salt of a weak acid to a solution of the weak acid: a)lowers the concentration of the nonionized acid and the concentration of the H30+ b)lowers the concentration of the nonionized
  25. Honors Chemistry

    "How many grams of NH3 can be produced from the reaction of 28 g of N2 and 25 g of H2? N2 + 3H2 ---> 2NH3 ==> 28 g N2 x (1 mol N2/14.0 g N2) x (2 mol NH3/1 mol N2) x ( 17.0 g NH3/ 1 mol NH3) = 68 g NH3 25 g H2 x ( 1mol H2/2.0 g H2) x (2 mol NH3/3 mol
  26. algebra

    find the y-intercept and the slope x + 2y -3 =0 You first have to get this into slope-intercept form: 2y=-x+3 y=-0.5x+1.5 This form is y=mx+b, where m is the slope and b is the y-intercept.
  27. chemistry

    An indicator has the reaction Hln(aq) ¡ê H+(aq) + In-(aq). Explain how the indicator can change color when a strong base is poured into a solution of this indicator. Will a strong base dissociate? Which way will this cause the reaction to shift? Is there
  28. Math

    A piece of wire is bent to form a square of area 121cm. Calculate: a)the length of each side of the square. b)the perimeter of the square. The piece of wire is now bent to form a circle using π=3.14 Calculate: a)the radius of the circle b)the area of
  29. English

    posted by rfvv Friday, April 13, 2018 at 9:46pm posted by rfvv Monday, April 9, 2018 at 10:21pm 1. What is the root verb of 'seen'? 2. What is the base verb of 'seen'? 3. What is the bare infinitive of 'seen'? 4. What is the verb root of 'seen'? 5. What is
  30. chemistry

    The first step of the synthesis is described by the reaction below. When 1.750 g of Fe(NH4)2(SO4)2 6H2O is mixed with 13 mL of 1.0 M H2C2O4 , the theoretical yield of FeC2O42H2O is ? grams.. I do not understand why my answer is not correct. How do you find
  31. Chemistry

    The experimentally determined rate law for the reaction H2 + NO --> ½N2 + H2O is Rate = k[H2][NO]2. Is the mechanism below possible? Step 1: H2 + NO --> N + H2O Slow Step 2: N + NO -->N2 + O Fast Step 3: O + H2 --> H2O Fast 1. Yes, because the
  32. Chemistry

    One of the concerns about the use of Freons is that they will migrate to the upper atmosphere, where chlorine atoms can be generated by the following reaction: CCl2F2 --> CF2Cl + Cl Chlorine atoms can act as a catalyst for the destruction of ozone. The
  33. Chemistry

    Translate the following sentences into unbalanced formula equations: (1) silver nitrate and soduim chloride react to form silver chloride and sodium nitrate. (2) iron (III) sulfate and calcium hydroxide react to form iron (III) hydroxide and calcium
  34. health

    How dose lock-and-key mechanism relate to hormones? A. If a hormone fits the receptor site, then there is no reaction. If a hormone and a receptor site do not match, then there will be an effect. B. If a hormone fits the receptor site, then there will be
  35. MAth 109

    The formula d= square root of 3h/2 models the distance, d, in miles, that a person h feet high can see to the horizon. If the pool deck on a cruise ship is 80' above the water, how far can passengers on the pool deck see? Write the answer in simplified
  36. Chemistry

    Please help me verify: The following reactions are involved in the formation of acid rain. Use oxidation numbers to identify which of these reactions are REDOX reactions. a. 2SO2(g) + O2(g) �� 2SO2(g) -2 -2 0 -2 -2 No change - not REDOX
  37. Math

    Which ratios does NOT form a proportion? 1. 24/96 , 27/108 2. 17/102 , 12/70 3. 21/51 , 35/85 4. 45/75 , 63/105 Which ratios form a proportion? Use cross products to test each pair. 1. 9/17 , 27/50 2. 12/35 , 24/75 3. 15/55 , 33/ 121 4. 12/35 , 20/70 Which
  38. Math (1 of 3)

    1. Simplify and write in standard form. Then, classify the polynomial by degree and number of terms [5x³ + 3x² - 7x + 10] + [3x³ - x² + 4x - 1] 2. Simplify and write in standard form. Then, classify the polynomial by degree and number of terms. [9w -
  39. Biochemistry

    You wish to measure the change in G°'for the hydrolysis of ATP: ATP ---> ADP + Pi but the equilibrium for the hydrolysis lies so far toward products that analysis of the ATP concentration at equilibrium is neither practical nor accurate. However, you
  40. Algebra

    write the equation of the line in slope-intercept form given the slope and the coordinates of the y-intercept m = 3/7;(0, 8/3) find an equation of the line described below. write the equation in slope-intercept form (solved for y) when possible. through
  41. chemistry(just need to clarify, no need to solve)

    When a sample of NO2(g) (5.641 mol) is placed in 360.0 L reaction vessel at 716.0 K and allowed to come to equilibrium the mixture contains 3.412 mol of NO(g). What is the equilibrium concentration (mol/L) of NO(g)? When a sample of PCl5(g) (1228 grams) is
  42. chemistry

    ​An empty glass container has a mass of 418.634 grams. It has a mass of 419.514 grams after it has been filled with nitrogen gas at a pressure of 790 mmHg and a temperature of 15oC. When the container is evacuated and refilled with a certain element
  43. Chemistry

    The decomposition of IBr(g)into I2 (g) and Br2 (g) is first order in IBr with k = 0.00255/sec. (a)Starting with [IBr] = 1.50M, what will [IBr] become after 2.50 minutes? (b)How long, in minutes, will it take for [IBr] to go from 0.500M to 0.100M? (c)What
  44. Chemistry - Equilibrium

    Can anyone find out if I did it right or not? Thanks A 0.682?g sample of ICl(g) is placed in a 625?mL reaction vessel at 682 K. When equilibrium is reached between the ICl(g) and I2(g) and Cl2(g) formed by its dissociation, 0.0383 g I2(g)is present. What
  45. spanish

    1). What is a "cognate"? 2). Why is learning cognates the most efficient and rapid way to learn to read, speak, increase vocabularly and get high marks on tests in a foreign language? Bonus question: What is the relationship between "cognates" and
  46. Chemistry

    In a study of the following reaction at 1200K it was observed that when the equilibrium partial pressure of water vapor is 15.0 torr, the total pressure at equilibrium is 36.3 torr. 3Fe(s)+4H2O(g) (reversible arrows) Fe3O4(s)+4H2(g) Calculate the value of
  47. Math

    What operation is used to change a fraction in simplest form to an equivalent fraction? What operation is used to change a fraction to simplest form?
  48. Chemistry

    a) An equilibrium exists between three chemical species in the blood , Hemoglobin, oxygenated hemoglobin and oxygen. Using the symbols Hb for hemoglobin , O2 for oxygen and HbO2 for oxygenated hemoglobin write out the equilibrium reaction. If you have
  49. chemistry

    if 37.9 liters of NO at .993atm and 146 degrees celcius are decomposed by the reaction 2NO-->N2+O2 how many grams of nitrogen will be formed... could you show mw step bu step how to do this ? thanks....i have finals tommorrow.... i need
  50. Pre-Calculus

    The treatment of a certain viral disease requires a combination dose of drugs D1 and D2. Each unit of D1 contains 1 milligram of factor X and 2 milligrams of factor Y, and each unit of D2 contains 2 milligrams of factor X and 3 milligrams of factor Y. If
  51. Math-check my work please??

    Write an equation, in point-slope form, for the line that is perpendicular to y – 10 = 3/2 (x – 4) and that passes through the point (4, 2). My Answer: Formula for point-slope form; y – y = m(x – x) Insert y and x value; y – 2 = m(x – 4) If the
  52. maths

    can you explain to me how to do this question i know i have to use differential equations but im not sure how to form an equation for inversely proportional question states grain is being poured at a steady rate to form a pile with height h, the rate at
  53. Art Appreciation

    Identify the step of the Critical Process that will require attentive observation as you explore attributes such as lines, color, and symmetry. A) Iconography/Subject Matter B) Medium and Technique C) Form D) Context and Which step of the Critical Process
  54. Maths

    The first odd number can be expressed as 1 = 1squared - 0squared. The second odd number can be expressed as 3 = 2squared - 1squared. The third odd number can be expressed as 5 = 3squared - 2squeared. a) Express the fourth odd number in this form. (Am I
  55. Physics, van de graff generators...

    When a small metal ball with a charge is placed in an electrical field supplie dby a van de graff generator, it experiences a force from the generator, and thus it applies a reaction force. But does the ball also apply a force met with a reaction force of
  56. ~CHEM~

    If I had an equilibrium of CH3CO2(aq) + H(aq) <=> CH3CO2H(aq) and the applied stress was HCl and NaOH what observations should I expect and what direction would the equliibrium shift? Same goes to this question equilibrium:Fe(aq) + SCN(aq) <=>
  57. Grammar (will you check these please)

    Rewrite the sentence or phrase using comparative form of the adverb 1. Approach slowly. = Approach more slowly. 2. Get well. = Get better. 5. Come quickly. = Come more quickly. 6. favorably received = most favorably received 8. far away = farther away 9.
  58. Math

    CHECK AND CORRECT MY ANSWERS!! PLEASE!!:D:D Write the ratio in the simplest form. 45:15 9:3 3:1*** 1:3 4:1 Solve the following proportion. (solve p) p/3 = 8/12 2*** 8 12 24 A recipe calls for 3 cups of flour to make 3 dozen cookies. Use the proportion to
  59. chemistry

    There are four main methods of making salts: Acid + Metal, Acid + insoluble base, Acid + alkali and solution of salt A + solution of salt B. a. a student wanted to make some sodium sulfate. i. which method would be best to use? ii. why? iii. which
  60. Chemistry

    Balance the reaction of plumbate ions and hydrochlorite ions: Pb(OH)42-(aq) + ClO-(aq) → PbO2(s) + Cl- I put: Pb(OH)3-(aq) + ClO-(aq) → PbO2(s) + Cl-(aq) + H2O(l) + OH-(aq) It said: The reaction described in your answer is not balanced. One or
  61. chemistry, please help

    2NO2(g)--> 2NO(g) + O2(g) , H=+114.2kJ (Note: H, S, G all have a degree sign next to them) NO: H(enthalpy)=90.3kJ/mol, S(entropy)=210.7J/mol*K, G(gibbs energy)=86.6 O2: H(enthalpy)=0, S(entropy)=?, G(gibbs energy)=0 kJ/mol NO2: H(enthalpy)=33.2,
  62. science

    these are my homework questions can you answer any???there are 4 1 A pupil placed some magnesium in a gas jar of oxygen How could the rate of reaction between these substances be increased 2 Complete the word equation for the reation magnesium and oxygen 3
  63. Algebra III / Core II

    It has been since the beginning of last year since I last did this math and the teacher I currently have is a sub and doesn't know what the heck she's doing either - so if anyone can help me, that'd be oh so amazing! a. Solve d=rt in terms of d and t. b.
  64. chemistry

    What is the equilibrium constant for the following reaction? 3A + 2B <---> 2C
  65. maths

    what is the equllibrium constant of KI + I2 reaction at 35 c?
  66. Science

    Reaction time.experiment
  67. thermodynamics

    H° = 565 kJ and S° = -11.1 J/K Calculate G° at 25°C for this reaction.
  68. bmcc

    which of the following is an oxidation reduction reaction ?
  69. Chemistry

    38. Identify the type of reaction. A + B --> AB A + BC --> AC + B Thanks -MC
  70. chemistry

    write the reaction for Zn + HCl
  71. chemistry

    reaction between Na2a2o3+licro4
  72. chemistry

    Why reversible reaction never complete
  73. science

    iron and sulphur reaction
  74. chemistry

    reaction between CuSo4+NaCl
  75. Chemistry

    Which reaction below represents the second ionization of Lr?
  76. chemistry

    Provide an example of a spontaneous reaction
  77. Science

    Is photosynthesis a endothermic reaction
  78. science

    describe the reaction of photosynthesis.
  79. Chemistry

    What is the equilibrium constant for the following reaction? 3A + 2B <---> 2C
  80. reaction

    conversion of cyclopropane to propene
  81. chemistry

    what happens in a condensation polymerization reaction?
  82. chemistry

    what type of reaction is Al+S8=Al2S3
  83. GCC

    PREDICT THE REACTION MG(NO3)2(AQ)+NA(S)
  84. chem

    Balance the Following Reaction: Mg(s) + H2O(g)Mg(OH)2(s) + H2(g)
  85. biology

    What will happen to the reaction without an enzyme?
  86. Chem

    NaOH (aq) + Zn (solid) reaction
  87. Chemistry

    Is photosynthesis a reversible reaction?
  88. Chemistry

    Balance the redox reaction: Ag(aq)+Cu(s)= Ag(s)+Cu(aq)
  89. Chemistry

    What is the reaction of dilute HCl with Zn?
  90. Chemistry

    Is esterification a condensation reaction?
  91. chemistry

    If you have 13.0g of Na, how many grams of O2 are required for the reaction?
  92. physics

    What does it mean when they say that action equals reaction?
  93. chemistry

    for a given reaction, the activation ener
  94. chem

    combination reaction. mg2+o2
  95. Chemistry

    How do you find a reaction order?
  96. chemistry

    when will a displacement reaction not occur?
  97. chemistry

    Why is respiration an exothermic reaction?
  98. chemistry

    Is there a reaction? 2 NaNO3 + ht →
  99. Chemistry 12

    Is O2(g) <---> O2(aq) an endothermic/exothermic reaction, and why?
  100. science

    what is the reaction between hexane & iodine?