# TIFFANY

Most popular questions and responses by TIFFANY
1. ## General Chemistry

The problem is: Calculate the standard free-energy change for the following reaction at 25 degrees Celsius. 2Au^+3(aq) + 3Cr(s)-> 2Au(s) + 3Cr^+2(aq) I worked it out, getting half reaction: Au^3+ + 3e- -> Au; E = 1.498 Cr^3+ + 3e- -> Cr; E = -0.74 Ecell =

2. ## Chemistry

Write and balance equation for the complete combustion of decane, C10H22

3. ## Math

At the amusement park, you decide to ride the Ferris wheel, which has a maximum height of 50 meters and a diameter of 35 meters. It takes the wheel 5 minutes to make one revolution. If you start your ride at the midline and the ferris wheel rotates counter

4. ## Chemistry!!!

Is the molarity of a solution that contains 6 moles of solute in 2 liters of solution 12 M????

5. ## Beowulf question

Why was it harder for Beowulf to kill Grendel's mother than Grendel himself?

6. ## Chemistry

if an excess of Al and 7.9 mol of Br2 are reacted in equation 2Al + 3Br2= 2AlBr2, how many moles of AlBr2 will be formed assuming a 100% yield

7. ## physics

A pitcher throws a 0.5kg ball of clay at a 6kg block of wood. The clay sticks to the wood on impact and their joint velocity afterwards is 3m/s. What is the original speed of the clay? I know the answer is 39m/s but I have no idea how they come up with

8. ## Chemistry (College) URGENT

1.6g of an unknown monoprotic acid (HA) required 5.79 mL of a 0.35 M NaOH solution to reach the equivalence point. Determine the molar mass of the acid and given that the pH at the half way point to the equivalent point is 3.86. Calculate the Ka of the

9. ## calculus

Which of the following are antiderivatives of f(x)=sinxcosx? I f(x)=(sin^2* x)/2 II f(x)=(cos^2* x)/2 III f(x)=-cos(2x)/4

10. ## ALGEBRA

A transformer has cooling fans that are set to come on when the temperature reaches 32° Celsius. The temperature is 90° Fahrenheit. Are the fans running?

11. ## chem 2

calculate kc for reaction I2 (g)+Cl2 (g)⇌2ICl(g )Kp=81.9 (at 298 K)

12. ## Physics

A cheetah can run approximately 100 km/hr and a gazelle at 80.0 km/hr. If both animals are running at full speed, with the gazelle 70.0 m ahead, how long before the cheetah catches its prey?

13. ## Chemistry

Silver chloride, often used in silver plating, contains 75.27% Ag. Calculate the mass of silver chloride required to plate 195mg of pure silver.

14. ## Chemistry

The problem is: Calculate the standard free-energy change for the following reaction at 25 degrees Celsius. 2Au^+3(aq) + 3Cr(s)-> 2Au(s) + 3Cr^+2(aq) I worked it out, getting half reaction: Au^3+ + 3e- -> Au; E = 1.498 Cr^3+ + 3e- -> Cr; E = -0.74 Ecell =

15. ## algebra 2

what is the answer to algebra with pizzazz page 100; what should you say if you see a tall, wrought-iron tower in paris, france? there are 24 blanks

16. ## 2008 math

Write the following as a sum using powers of 10 to show place value and explain your steps. 3) 620.83

17. ## Chemistry

A compound containing only C, H, and O was extracted from the bark of the sassafras tree. The combustion of 36.3mg produced 98.6 of CO2 and 20.2mg of H2O. The molar mass of the compound was 162 g/mol. Determine its empirical and molecular formulas

18. ## statistics

David wants to rent an unfurnished apartment for next semester. He took a random sample of 9 apartments adversised in the local Halifax paper, and recorded the rental rates. The rents (in \$ per month) were: 500 650 600 505 450 550 515 495 640 a) Find a 90%

19. ## Chemistry

If 0.150 moles of salicylic acid and execs acetic anhydride are used during a synthesis of aspirin, how many grams of aspirin will be obtained if the reaction gives a 38% yield?

20. ## Chemistry

A mass of 0.4113 g of an unknown acid, HA, is titrated with NaOH. If the acid reacts with 28.10 mL of 0.1055 M NaOH, what is the molar mass of the acid?

21. ## Math

Tommy has 5 jars. Each jar is 2/3 filled with marbles. How many full jars of marbles does tommy have ?

22. ## college algebra

The​ half-life of​ carbon-14 is 5600 years. If a piece of charcoal made from the wood of a tree shows only 73​% of the​ carbon-14 expected in living​ matter, when did the tree​ die?

23. ## Physics

Josh starts his sled at the top of a 3.0m high hill that has a constant slope of 25 degrees. After reaching the bottom, he slides across a horizontal patch of snow. The hill is frictionless but the coefficient of kinetic friction between his sled and the

24. ## Calculus

Find the area of the indicated region. We suggest you graph the curves to check whether one is above the other or whether they cross, and that you use technology to check your answer. Enclosed by y = x^2 − 4x + 1 and y = −x^2 + 4x − 5

25. ## computers

Wendy calls the help desk and reports that she is unable to access her files that are stored on the server. The network is a Windows Domain with Active Directory. Wendy is logged on locally to her workstation that runs Windows 8. You remote into her

26. ## physics!

A 1.60-kg bottle of vintage wine is lying horizontally in a rack. The two surfaces on which the bottle rests are 90.0° apart, and the right surface makes an angle of 45.0° with respect to the horizontal. Each surface exerts a force on the bottle that is

27. ## Writing

Expository writing prompt: Describe a family celebration that has special meaning for you. Please give me some feedback. Every year my uncle celebrates Christmas at his house. Unlike the common Christmas party where people hand out presents to other

28. ## Chemistry

Find the volume of 0.250M sulfuric acid necessary to react completely with 79.3g sodium hydroxide

29. ## Urgent-Chemistry Help

I need help with the heat effects and calorimetry worksheet. Please explain how to solve it! Thank you so much! A metal sample weighing 45.2g and at a temperature of 100.0 C was placed in 38.6g of water in a calorimeter at 25.6 C. At equilibrium the

30. ## Physics

A record player rotates a record at 45 revolutions per minute. When the record player is switched off, it makes 5 complete turns at a constant angular acceleration before coming to rest. What was the magnitude of the angular acceleration (in rads/s2) of

31. ## General Education

Only circus animals with a clean bill of health will perform in today’s exhibition. A monkey, a poodle, and a horse will perform in today’s exhibition. No circus animals with a clean bill of health were prescribed medications this week. If the

32. ## Chemistry

A student placed 17.0 g of glucose (C_6H_{12}O_6) in a volumetric flask, added enough water to dissolve the glucose by swirling, then carefully added additional water until the 100 mL mark on the neck of the flask was reached. The flask was then shaken

33. ## Physics 202

A rail gun uses electromagnetic forces to accelerate a projectile to very high velocities. The basic mechanism of acceleration is relatively simple and can be illustrated in the following example. A metal rod of mass 10.0g and electrical resistance 0.100Ω

34. ## General Education

Memmie: The greater the population near a restaurant, the more potential customers it has and the greater chance its popularity will spread through word-of-mouth. O’Sullivans Restaurant just opened in the very densely populated town of Redville, so its

35. ## Math 75

if you paid \$120 to a loan company for the use of \$2000 for 90 days, what annual rate of interest did they charge?

36. ## General Education

Aron: The two double A batteries in my CD player are dead, so the CD player doesn’t work. My television remote control, which also uses two double A batteries, works fine. So if I move the two batteries from my television remote control to my CD player,

37. ## Chemistry

To increase the solubility of a gas at constant temperature from 1.20 g/L at 1.4 atm to 2.3 g/L what would the pressure have to be increased to?

38. ## math

Noah wants to display his 72 collectors flags.he is going to put 6 flags in each row.how many rows of flags will he have in his display?

39. ## Chemistry

NH4+ + OH- NH3 + H2O What is the K for the reaction above in terms of Ka's, Kb's, Kw etc.?

40. ## Practical English

What is the topic sentence in this paragraph? (1)A trip to the ocean can be a relaxing escape from the everyday pressure of life. (2)A sailboat glistening on the horizon provides a mental escape to faraway places. (3)the rhythm of the ocean beating against

41. ## smith

The Smiths want to buy a 9 ft. by 12 ft. carpet and center it in a 15 ft. by 20 ft. room. What is the area of the carpet?

42. ## Social Studies

Why did the Pilgrims' government come about and why was its existence important. I know this has to do with the Mayflower Compact and was a formal method to establish systematic order among the Pilgrims but not sure why it came about and the importance.

43. ## Chemistry

An antacid contains 200mg of aluminum hydroxide and 200mg of magnesium hydroxide per capsule. a. How many moles of Al(OH)3 does each capsule contain? 2.56 x 10^-3 mol Al(OH)3 is that correct? b. What is the mass in milligrams of 0.0457 mole of magnesium

44. ## Physics

The earth has about 80 times the mass of the earth’s moon. The gravitational force exerted on the moon by the earth has what relation to the gravitational force exerted on the earth by the moon? 1. the same as 2. zero; the earth exerts a force on the

45. ## physics

nucleus of oxygen-15 undergoes electron capture. Write out the reaction equation and determine the identity of the daughter nucleus

46. ## chemistry

What volume of 16 M nitric acid must be diluted with distilled water to prepare 500.0 mL of 0.50 M HNO3?

47. ## Chemistry

How many kilograms of chlorine are in 22 kg of each of the following chlorofluorocarbons CFCs? 1.CF2Cl2 2.CFCl3 3.C2F3Cl3 4.CF3Cl

48. ## Chemistry

Give the formula of each of the following copper minerals: A. cuprite, copper (I) oxide B. chalcocite, copper (I) sulfide C. covellite, copper (II) sulfide

49. ## Physics

Why are the tires for trucks carrying gasoline and other ﬂammable ﬂuids manufactured to be electrically conducting? 1. To make the truck easier to drive 2. To move the positive charges from the truck to the ground and avoid ﬁre 3. To neutralize the

50. ## calculus

1. A conical reservoir has a depth of 24 feet and a circular top of radius 12 feet. It is being filled so that the depth of water is increasing at a constant rate of 4 feet per hour. Determine the rate in cubic feet per hour at which water is entering the

51. ## chem

Determination of the solubility product of PbI2. From the experimental data we obtain [I-] directly. To obtain Ksp for PbI2, we must calculate [Pb2+] in each equilibrium system. This is most easily done by constructing an equilibrium table. We first find

52. ## intro to computers

You call the help desk to report a problem you are having on your computer. The technician asks you what operating system you are running. You know it is Windows 7 but you forget which version. How can you find out?

53. ## physics

A ball is thrown straight downward from the surface of the moon. Is the maximum height it reaches less than, equal to, or greater than the maximum height reached by a ball thrown upwards on the earth with the same initial speed? Ignore air resistance in

54. ## physics

the frequency of middle C on a piano is 261.6hz. What is the wavelength of sound as it travels @room air and in water?

55. ## Chemistry II

At a certain temperature, Kc = 33 for the reaction: H2(g) + I2(g) 2HI(g) Assume that the initial concentrations of both H2 and I2 are 6.00 x 10-3 mol/L. Find the concentration of each reactant and product at equilibrium.

56. ## Grammar (will you check the rest please)

FIND THE ADVERB AND THE WORD IT MODIFIES 1. Mac looked everywhere for his jacket but could not find it.EVERYWHERE MODIFIES LOOKED AND FIND MODIFIES COULD 2. Tom threw the ball fast and hard. FAST, HARD MODIFIES THREW 3. Soon it will be time to go to sleep.

57. ## Chemistry- Writing Net Ionic equations

I need to write the net inonic equation for (NH4)2SO4(aq) and KNO2(aq). I need to know the reactants and the product. I worked it out and got: 2K+(aq) + SO4-(aq) ----> K(SO4)2(s)

58. ## Chemistry

Fill in the missing information in the following table of four neutral atoms Symbol- 37Cl number of protons- 36 46 number of neutrons- 42 number of electrons- 33 mass number- 77 106

59. ## Physics

A person pushes on a 60-kg refrigerator with a horizontal force of -260 N; the minus sign indicates that the force points in the -x direction. The coefficient of static friction is 0.68. (a) If the refrigerator does not move, what are the magnitude and

60. ## Chemistry

Calculate the enthalpy change in kJ when 21.6g of H2S is burned. 2H2S(g) + 3O2(g) --> 2SO2(g) + 2H20(g) Change in H=-1036kJ/mol

61. ## Chemistry

how many grams of NaCN would you need to dossolve in enough water to make exactly 250.0mL of soultion with pH of 10.00?

62. ## chemistry

how to write this as a net ionic equation? Al(s)+ H2SO4(aq)

63. ## chemisty

what is the final pH after 1 drop(.05ml) of 6M HCl is added to 1.0L of freshly prepared pure water that was originally at a pH of 7.0. Is there a signigicant pH change?

64. ## Grammar (will you check the rest please)

FIND THE ADVERBS 1. Pedro enthusiastically supported Zach's bid for student council president. ENTHUSIASTICALLY 2. Spend your money wisely. WISELY 3. Marissa waited quietly for the play to begin. QUIETLY 4. Lightly underline the words you want to

65. ## statistics

a machine has 0.04 probability of producing a defective item. If it produces 6 items find: a. probability none is defective b. at least one is defective c. all are defective

66. ## Physics

Sound of a certain wavelength is coming from within a room and passing through a rectangular door (a "slit"). If the width of the doorway is twice the wavelength of the sound, what is the diffraction angle è of the sound leaving the doorway? Please show

67. ## Chemistry

The specific heat of solid copper is 0.385 J/g*C. What thermal energy change occurs when the temperature of a 40.10g sample of copper is cooled from 42.9C to 10.0C? Be sure to give you answer the proper sign. I know this is part of the answer which

68. ## PHYSICS

Two horizontal forces, F1 and F2, are acting on a box, but only F1 is shown in the drawing. F2 can point either to the right or to the left. The box moves only along the x axis. There is no friction between the box and the surface. Suppose that = +6.2 N

69. ## economics

Give two examples of price discrimination. In each case, explain why the monopolist chooses to follow this business strategy.

70. ## Physics

A plastic rod is rubbed against a wool shirt, thereby acquiring a charge of −4.9 µC. How many electrons are transferred from the wool shirt to the plastic rod? The elemental charge is 1.6 × 10^-19C.

71. ## chemistry

Imagine that you have a 7.00 gas tank and a 3.50 gas tank. You need to fill one tank with oxygen and the other with acetylene to use in conjunction with your welding torch. If you fill the larger tank with oxygen to a pressure of 115 , to what pressure

72. ## Physics!

One of the new events in the 2002 Winter Olympics was the sport of skeleton (see the photo). Starting at the top of a steep, icy track, a rider jumps onto a sled (known as a skeleton) and proceeds - belly down and head first - to slide down the track. The

73. ## Physics (76)

the weight of the block on the table is 422 N and that of the hanging block is 185 N. Ignoring all frictional effects and assuming the pulley to be massless, find (a) the acceleration of the two blocks and (b) the tension in the cord.

74. ## Social Studies

South Africa gained its independence from Britain in 1910. Why did this not lead to freedom and equality in South Africa?

75. ## Chemistry

Calculate the total heat energy needed to convert 110g of ice at -10°C to steam at 110°C..?

76. ## Physics

The ends of a light string are tied to two hooks A and B in a ceiling which are 100 cm apart horizontally so that the length between hooks is 140 cm. A 650g mass is then attached by a second length of string to a point C on the first, 80 cm from A, and

77. ## Physics

How much energy is required to change a 58 g ice cube from ice at −1◦C to steam at 101◦C? The specific heat of ice is 2090 J/kg ·◦ C and of water 4186 J/kg ·◦ C. The latent heat of fusion of water is 3.33 × 105 J/kg, its latent heat of

78. ## Physics

A 123 g cube of ice at 0◦C is dropped into 1.9 kg of water that was originally at 81◦C. What is the final temperature of the water after after the ice melts? The latent heat of fusion of water is 3.33 × 105 J/kg . Answer in units of ◦C

79. ## economics

You are hired as the consultant to a monopolistically competitive firm. The firm reports the following information about its price, marginal cost, and average total cost. Can the firm possibly be maximizing profit? If not, what should it do to increase

A long distance swimmer is able to swim through still water at 4km/hr. She wishes to swim from Port Angeles, WA due north to Victoria, B.C., a distance of 50km. An ocean current flows through the Strait of Juan de !@#\$%^&a from west to east at 3km/hr. In

81. ## Chemistry

Calculate the mass of Fe(OH)3 s) produced by mixing 50.0 mL of 0.153 M KOH (aq) and 25.0 mL of 0.255 M Fe(NO3)3 (aq), and the number of moles of the excess reactant remaining in solution. I got 0.00383 mol Fe(NO3)3 remaining. I don't know how to obtain the

82. ## Chemistry

Calculate the solubility of LaF3 in grams per liter in the following solutions. The Ksp of LaF3 is 2.01 e-19. (a) pure water (b) 0.051 M KF solution (c) 0.065 M LaCl3 solution

83. ## Chemistry

For a particular isomer of C8H18, the following reaction produces 5104.1 kJ of heat per mole of C8H18(g) consumed, under standard conditions. (deltaH_rnx = -5104.1kJ) What is the standard enthalpy of formation of this isomer of C8H18(g)?

84. ## chemistry

Which of the following statements is (are) true about a compound that has a molecular ion peak in its mass spectrum at mass 94, and shows prominent peaks in its IR spectrum at 3600–3200 and 1600 cm–1? A) The compound has a molecular mass of 94. B) The

85. ## chemistry

If the solubility of a particular solute is 10 g/100 g H2O at 20 oC, which of the following would represent a supersaturated solution of that solute: a) 9 g/100 g H2O at 20 oC, or b) 11 g/100 g H2O at 20 oC.

86. ## Brief Calculus

The demand function for a certain make of replacement cartridges for a water purifier is given by the following equation where p is the unit price in dollars and x is the quantity demanded each week, measured in units of a thousand. p = −0.01x2 − 0.3x

87. ## Physics help!

An extreme skier, starting from rest, coasts down a mountain that makes an angle of 26.7 ° with the horizontal. The coefficient of kinetic friction between her skis and the snow is 0.248. She coasts for a distance of 10.5 m before coming to the edge of a

88. ## PHYSICS!!

Air rushing over the wings of high-performance race cars generates unwanted horizontal air resistance but also causes a vertical downforce, which helps cars hug the track more securely. The coefficient of static friction between the track and the tires of

89. ## Chemistry

How would the calculated concentration of the HCI be affected, if the sodium hydroxide were poured from a beaker that contained some water before that NaOH were added to it ?

90. ## Math

On a Science exam Rita answered 36 questions correctly and receive a score of 100% her friend answered 27 questions correctly what score did read her friend receive

91. ## Bus.Math

John O'Sullivan has just completed his first year in business. His records show that he spent the following in advertising: Newspaper \$725 Radio \$525 Yellow Pages \$700 Local flyers \$425 What percent of John's advertising was spent on the Yellow Pages?

92. ## spanish

In the following sentences, change the position of the reflexive pronouns so that sentences retain their meaning. Have the correct account punctuation and accentuation. 1. Ellos vienen a despedirse esta noche 2. Daniel se esta afeitando 3. Patricia va a

93. ## english

1. Which of the following statements about Saadi's sayings is not true? A) They offer practical advice. B) They use simple language. C) They were composed in a time of chaos. D) They were written for other mystics. 2.What is a rubáiyát? A) a Chinese poem

94. ## Computers (Internet)

Is this considered plagiarism? Original passage: A letter of thanks is a courteous acknowledgment of a gift or of something that was done for you. Another passage: A thank you note is a polite acknowledgment of a present or something nice someone did for

Sally has three times as many dimes as nickels and twice as many quarters as dimes.In all she has \$5.55. How many coins of each type does she have? Let 2x=quarters 3x=dimes x=nickles

96. ## Calculus

Find the area of the indicated region. We suggest you graph the curves to check whether one is above the other or whether they cross, and that you use technology to check your answer. (Round your answer to three decimal places.) Between y = e^x and y = x

97. ## Computers (internet)

How would you know whether a particular article from Wikipedia is accurate?

98. ## Math

I am really have a tough time trying to solve this problem. I think my first three steps are correct but I am not sure. Could someone please help me? I got lost somewhere on one of these steps. I thonk it was step 3, 4, 5. Thank you. The two numbers chosen