# Natalie

Most popular questions and responses by Natalie
1. ## chemistry

Arrange the following aqueous solutions in order of decreasing freezing points (lowest to highest temperature): 0.10 m Na3PO4, 0.35 m NaCl, 0.20 m MgCl, 0.15 m C6H12O6 and 0.15 m CH3COOH.

2. ## College Physics

In a crash test, a 2000-kg van collides with a concrete support. The stopping time interval for the collision is 0.10 s, and the impulse exerted by the support on the van is 7.0×103N⋅s. A.) Determine the magnitude of the change in momentum. B.)Determine

3. ## chem

A sample of oxygen gas was collected via water displacement. Since the oxygen was collected via water displacement, the sample is saturated with water vapor. If the total pressure of the mixture at 26.4 °C is 725 torr, what is the partial pressure of

4. ## Chemistry

(NH4)2S is a strong electrolyte. Determine the concentration of each of the individual ions in a 0.200 M (NH4)2S solution. [NH4] = M [S] = M

5. ## PHYSICS

A and B run around a circular track whose cicumference is 150m. when they run is opposite directions they meet every 5 seconds, but when they run in the same direction from the some point they are together every 25 seconds. what are their rates? ans. 18m/s

6. ## Calculus I

Hello, The pressure P and volume V of an expanding gas are related by the formula PVb=C, where b and C are constants (this holds in adiabatic expansion, without heat gain or loss). Find dPdt if b=1.6, P=12kPa, V=80cm2, and dVdt=20cm3/min. Thus far, I got

7. ## English

In high school we have to read great expectations by Charles !@#\$%^&ens for honors English but i do not understand the essay I have to write. Could someone help me please? Compare and contrast the ways in which the protagonist is stuck between two worlds,

8. ## Chemistry

If you need to prepare 250.0 mL of a pH 5.00 buffer that has a total buffer concentration of acetic acid + sodium acetate of 0.050M, how many moles of each will you need to prepare the solution? Given solutions of acetic acid and sodium acetate with

9. ## Chemistry

Assume that the normal blood buffer contains 0.00080 M carbonic acid and 0.0085 M hydrogen carbonate, the pKa = 6.35 for carbonic acid and the volume of blood in the body is 7.00 L. The blood pH, due to disruption is now 7.20. What is the ratio of

10. ## Government

Hello, I need this question explained. You don't have to give me the answer ,but I just need a break down ..in order to know what direction i need to go in. I know what it means to be political..I guess Im just confused by the question. Please Help ! (

11. ## English

In the sentence "There comes a time when the cup of endurance runs over, and men are no longer willing to be plunged into an abyss of injustice," the bolded phrase creates a mood of __________ among the audience A.Panic B.Despair C.Anger D.Anticipation

12. ## Chemistry

A mole of methane reacts with 64g of oxygen at 1 atm, 425 K. There are two ways in which methane can react with oxygen. It can either form water vapor and carbon dioxide or water vapor and carbon monoxide. After reaction the final gas density is 0.7282

13. ## Physics

a 0.30-m radius automobile tire rotates how many rad after starting from rest and accelerating at a constant 2.0 rad/s^2 over a 3.54-s interval

14. ## Chemistry

-Consider the reaction when aqueous solutions of silver(I) nitrate and manganese(II) chloride are combined. The net ionic equation for this reaction is? -Consider the reaction when aqueous solutions of cobalt(II) sulfate and lead(II) nitrate are combined.

15. ## science

Name the type of reaction that the equation represents? 2Cu + O2 -------> 2CuO

16. ## Physics

Two blocks are connected by a string on a pulley. One block is on an incline, and the other is hanging. The smooth inclined surface makes an angle of 35 ∘ with the horizontal, and the block on the incline has a mass of 5.7 kg. The mass of the hanging

17. ## TX HISTORY; HELP ASAP

How did fighting in the civil war change the lives of Texas soldiers ? a) They came to support the cause of secession b) They traveled far from home to participate in bloody battles c) They earned enough money to buy cotton plantations and slaves d) They

18. ## Math

Jamie spenta total of \$11.60 on 5dentical pens and a ruler .A rulercost\$1.30less than a pen .how much did a pen cost?

19. ## science

1.40g each of CO, H2O, and H2 are sealed in a 1.41−L vessel and brought to equilibrium at 600 K. CO(g)+H2O(g)⇌CO2(g)+H2(g)KC=23.2 How many grams of CO2 will be present in the equilibrium mixture?

20. ## BOB

A sphere of radius 20 cm and mass 1.80 kg starts from rest and rolls without slipping down a 30.0 degree incline...

21. ## Physics

A person pushes on a 62-kg refrigerator with a horizontal force of -256 N; the minus sign indicates that the force points in the −x direction. The coefficient of static friction is 0.61. (a) If the refrigerator does not move, what are the magnitude and

22. ## Calc

A cup of coffee at 90 degrees celsius is put into a 30 degree celsius room when t =0 . The coffee's temperature, f (t ) , is changing at a rate given by f '(t )=-8(0 .8) t degrees celsius per minute, where t is in minutes. Estimate the coffee's temperature

23. ## Precalculus with Trigonometry

Prove or disprove the following identity: (sin(10x))/(sin(x)+sin(9x)) = (cos(5x))/(cos4x))

24. ## Chemistry

Iodine 131 is a radioactive isotope. After 4.00 days, 70.8% of a sample of 131I remains.What is the half life of 131I?

25. ## Chemistry

Calculate the change in the enthalpy of the reaction. C4H4(g)+2H2(g)===>C4H8(g) Use the following: change in enthalpy of combustion for: C4H4=-2341 kJ mol-1 H2=-286 kJ mol-1 C4H8=-2755 kJ mol-1

26. ## algebra 1

does 4x+5y=0 represent a direct variation? if so, find the constant of variation. complete the steps to solve 4x+5y=0 for y.

27. ## Social Studies *Check Answers*

Anyone mind checking these 2 quiz answers please? Which statement best explains why nation-states write constitutions? A: Constitutions give citizens unlimited powers. B: Constitutions establish nation-states. C: Constitutions allow governments to elect

28. ## Chemistry

Calculate the standard enthalpy of formation of CuO2, given that: 2Cu2O + O2 ==> 4 CuO (-288 kJ) Cu2O ==> Cu + CuO (11 kJ) PLEASE HELP!!!!

29. ## Chemistry

How many lone pairs are in a chlorite ion (CLO2)- ?

30. ## College Physics

You are on vacation in San Francisco and decide to take a cable car to see the city. A 6100-kg cable car goes 410 m up a hill inclined 16 ∘ above the horizontal. The system is the car and Earth. Determine the change in the total energy of the system when

31. ## Math

Marissa bought 2 1/4 gallons of orange juice to make punch. How many qts of oj did she buy? Marissa bought 6 fewer pints of soda than oj. How many cups of soda did she buy?

33. ## Chemistry

A piece of copper metal is initially at 100 C. It is dropped into a coffee cup calorimeter containing 50.0 g of water at a temperature of 20 C. After stirring, the final temperature of both copper and water is 25 C Assuming no heat losses, and that the

34. ## Math

write an inequality to represent the situation: The temperature stayed above -15

35. ## statistics

Can someone help me with this questions. Find the variance for a given data. Rpund your answer to one more decimal place then the original data. Compute the variance. Jeanne is currently taking college zoology. The instructor often gives quizzes. On the

36. ## PHYSICS

A hypothetical planet has a mass 1.55 times that of Earth, but the same radius. What is g near its surface?

37. ## Chemistry

A piece of copper metal is initially at 100 C. It is dropped into a coffee cup calorimeter containing 50.0 g of water at a temperature of 20 C. After stirring, the final temperature of both copper and water is 25 C Assuming no heat losses, and that the

The depth d of water in a tank oscillates sinusoidally once every 4 hours. If the smallest depth is 7.9 feet and the largest depth is 10.1 feet, find a possible formula for the depth in terms of time t in hours. (Let the water depth be at the average when

39. ## science

how physical/mechanical and chemical weathering different?

40. ## Home Economics

List 5 careers that are possible from 3 areas in Home Economics. Why don't you list the areas of Home Economics first, then match those areas up with careers. I can think of cooking, sewing, (by the way, most Home Ec departments now prefer to be called

41. ## math

For tax purposes, you may have to report the value of your assets, such as cars or refrigerators. The value you report drops with time. "Straight-line depreciation" assumes that the value is a linear function of time. If a \$1020 refrigerator depreciates

42. ## phsical science

a tire contains air ata pressure of 2.8 bar at 10 degree celsius.if the tires volume is unchanged what will the air pressure in it be when the tire warms up to 35 degree celsius if the car is driven.

43. ## Calculus

Find the derivative of y with respect to x. y= (lnx)/(3+4lnx) Should I start by using the quotient rule?

44. ## algebra 1

a bout travels 280 miles downstream and back. The trip downstream took seven hours. The trip back took 14 hours. The speed of the boat in still water and the speed of the current

45. ## accounting

The balance in the unearned fees account before adjustment at the end of the year is 112,790. Of these fees, 69,735 have been earned. In addition, 13,200 of fees have been earned but have not been billed. Journalize the entry to the adjust the unearned

46. ## Physics

As two trains move along a track, their conductors suddenly notice that they are headed toward each other. The figure below gives their velocities v as functions of time t as the conductors slow the trains. The slowing processes begin when the trains are

47. ## Calc

t 0 5 10 r(t)0 90 0 A shop is open 9 AM - 7 PM. The function r(t), gives the rate at which customers arrive (in people/hour) at time t, where t measures time in hours since 9 AM. Suppose that the salespeople can serve customers at a rate of 75 people per

48. ## Chemistry

A piece of copper metal is initially at 100 C. It is dropped into a coffee cup calorimeter containing 50.0 g of water at a temperature of 20 C. After stirring, the final temperature of both copper and water is 25 C Assuming no heat losses, and that the

49. ## Chemistry

1) A compound has the following percentages by mass: barium, 58.84%; sulfur, 13.74%; oxygen, 27.43%. Determine the empirical formula of the compound. 2) If a 1.271-g sample of aluminum metal is heated on a chlorine gas atmosphere, the mass of aluminum

50. ## Math

Fay's rubber ball bounces exactly half the height from which it is dropped. She drops the ball from the top of a building that is 64 meters tall. How high will the ball bounce on its eighth bounce. Could someone explain this? Thank you! Natalie 1/2 of 64=

51. ## Physical Education

What is the pelvis? At Least 3 sentences.

52. ## math

The desert temperature, H, oscillates daily between 36°F at 4 am and 56°F at 4 pm. Write a possible formula for H in terms of t, measured in hours from 4 am. I thought the answer is -10cos(1/6pi times t) +46 but it got marked wrong. I thought that the

53. ## chemistry

If 6.30 moles of C5H12 reacts with excess O2, how many moles of CO2 will be produced in the following combustion reaction?

For a boat to float in a tidal bay, the water must be at least 2.7 meters deep. The depth of the water around the boat, d(t), in meters, where t is measured in hours since midnight, is d(t) = 5 + 4.6 sin(0.5t). (a) What is the period of the tides in hours?

55. ## Physics

Consider the equation v = 1/8zxt2. The dimensions of the variables v, x, and t are [L]/[T], [L], and [T], respectively. The numerical factor 8 is dimensionless. What must be the dimensions of the variable z, such that both sides of the equation have the

56. ## World History

Both Stalin in the Soviet Union and Hitler in Germany instituted ruthless campaigns against supposed enemies of the state. Why do you think dictators need to find scapegoats for their nation's ills?

57. ## chemistry 12

sry, a misprint. its: O2+2F2 2OF2 The question is looking for Kc. 2.50 mo of oxygen and 2.50 mol of fluorine gas are placed in a 2.00L glass container at room temperature. The container is heated to 400K and the following equilbirum is established: O2+2F2

58. ## Chemistry

How do I find the molar enthalpy H (kJ/mol) for reaction of NH3 + HCl -> NH4Cl at temp 9.8 celsius by using Hess's Law. I do not understand why there are unknown variables and how to use that to find the molar enthalpy. PLEASE HELP. 1/2 N2 + 3/2 H2 + xH2o

59. ## Chemistry

A piece of copper metal is initially at 100 C. It is dropped into a coffee cup calorimeter containing 50.0 g of water at a temperature of 20 C. After stirring, the final temperature of both copper and water is 25 C Assuming no heat losses, and that the

60. ## Calculus II

Sketch the region enclosed by 2y=5x^(1/2), y=3, 2y+4x=9. Decide whether to integrate with respect to x or y, and then find the area of the region.

62. ## Physics

A 2.0kg object initially at rest explodes breaking into two pieces of mass 5.0kg and 15.0kg. If the 15.0kg piece moves with a speed 2m/s what is the speed of the 5.0kg piece? A. -6 m/s B. 15 m/s C. -5 m/s D. 20 m/s

63. ## Language Arts

3 main points for a speech on the alphabet

64. ## Math

Jill and Matt run on a 400-meter-long oval track. They each run 10 laps daily and both run in the same lane. One day, they begin at the same point, but ran in opposite directions. Jill ran at a constant speed that was 2 meters per second faster than Matt's

65. ## Calculus 2

Find the area bounded by the curves y=sin(4x) and y=0 for x between x=0 and x=3pi/8.

66. ## math

Emma os using connecting cubes to make a rectangular model with a height of one connecting cube. With her cubes she can make the model in exactly 3 different ways. If Emma has more than 12 but fewer than 17 cubes how many cubes does she have

67. ## physics

As some molten metal splashes, one droplet flies off to the east with initial speed vi at angle θi above the horizontal, and another droplet flies off to the west with the same speed at the same angle above the horizontal, as inthe figure. In terms of vi

68. ## math

A town has a population of 2000 people at time t = 0. In each of the following cases, write a formula for the population, P, of the town as a function of year t. (a) The population increases by 60 people per year. I thought it would be P= 2000 (1.03)^t (b)

69. ## Chemistry

how much heat is absorbed when 63.7 grams of water at 100 degrees Celsius is converted to steam at 100 degrees Celsius? -I need help figuring out how to do this.

70. ## physics

A 590 kg racing car completes one lap in 14.3 seconds around a circular track with a radios of 45.0 meters. The car moves at constant speed. (A) what is the acceleration of the car? (B) what force must the track exert on the tires to produse this

71. ## Chemistry

You have a stock solution of 14.4 M NH3. how many mililiters of this solution should you dilute to make 1050mL of .220 M NH3 answer 16.o mL Question if you take a 10.5mL portion of the stock solution and dilute it to a total volume of .600L, what will be

72. ## chemistry

What is the original molarity of an aqueous solution of ammonia (NH3) whose pH is 11.10 at 25 degrees C? (Kb for NH3=1.8 x 10^-5)

73. ## ochem

when the concentration of CHBr3 and NaOH are both .145, the rate of the reaction is .0040 M/s. What is the rate of the eaction if the concentration of CHBr3 is doubled?if the conc. is halved?if the two conc. are both increased by a factor of five?

74. ## Math

Dee used 2 1/3 cups of sugar for a cake recipe. If the amount of sugar the container holds is 3 times the amount she used, does the container hold more than, less than, or equal to 3 cups of sugar? Explain.

75. ## science

Michael thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're supposed to staple a set of papers). Group A is given the special juice to

76. ## Chemistry

If you add 13.75 mL of 1.35 M HCl to 22.80 mL of 0.955 M Ca(OH)2, will you neutralize all the Ca(OH)2? You must show data to support your answer.

77. ## Physics

a 12 kg physics book flies through the air with a momentum of 20kg m/s. what is its speed?

78. ## physics

A car is traveling at 45.0 mi/h on a horizontal highway. (a) If the coefficient of static friction between road and tires on a rainy day is 0.100, what is the minimum distance in which the car will stop? ____ m (b) What is the stopping distance when the

79. ## Chemistry

Can someone PLEASE help me with this???? I am soooo confused with this problem!!! Combustion reactions involve reacting When compounds containing carbon and hydrogen are combusted, carbon dioxide and water are the products. Using the enthalpies of

80. ## Math

A pizza shop charges \$2.00 for a slice that is one-eighth of a pizza and \$3.00 for a slice that is one-fourth of a pizza. One day the pizza shop makes 6 pizzas. How much more money will they make if they slice all the pizzas into eighths than if they slice

81. ## Chemistry

If it takes 22.75 mL of 1.75 M H3PO4 to neutralize 14.90 mL of Al(OH)3, what is the molarity of the Al(OH)3?

82. ## chemistry

1) A Galvanic cell runs on the following reaction: Co (s) + Cu2+ (aq) → Co2+ (aq) + Cu (s) Draw a diagram for this Galvanic cell, labeling the electron flow, the anode and cathode, and the positive and negative sides of the Galvanic cell. 2) A Galvanic

83. ## Physics

A woman holds a 1.90-m-long uniform 5.0-kg pole as shown in (Figure 1) ( its horizontal). A. Determine the force she must exert on the pole at A. Express your answer to two significant figures and include the appropriate units. Enter positive value if the

84. ## statistics

If an instrument requires some professional judgments in scoring, then the manual should also include information on a. Interrater RELIABILITY b. Corrections of the reliability coefficients using the Spearman-Brown formula c, Both KR 20s and KR 21s d. Test

85. ## Physics

An Earth satellite moves in a circular orbit at a speed of 5800 m/s. a)What is the radius of the satellite's orbit? b) What is the period of the satellites orbit in hours?

86. ## Math

Using a number cube, how could you use it to simulate a 66% chance?

Assuming that limits as x → ∞ have the properties for limits as x → c, use algebraic manipulations to evaluate lim x → ∞ for the function. a. f(x) = x − 2/2 + 6x^2 b. f(x) = x^2 + 6/x + 7 Please help! I do not know how to start with this

88. ## math

Triangle ADE is inside rectangle ABCD. Point E is half way between points B and C on the rectangle. Since AB is 8 cm and side AD is 7 cm. 1. what is the area of triangle ADE? 2. what is the ratio of the area of the triangle ABE to the area of triangle ADE?

89. ## College Physics

A person who is properly constrained by an over-the shoulder seat belt has a good chance of surviving a car collision if the deceleration does not exceed about 30 "g"s (1.0 g= 9.8m/s^2) Assumind uniform deceleration of this calue calculate the distance

90. ## Chemistry

How many grams of NH3 can be produced from 3.26 moles of N2? How many grams of H2 are needed to produce 13.99 g of NH3?

91. ## physics

What potential difference is required to reduce the initial speed of the proton by a factor of 2? A proton has an initial speed of 3.1×105 m/s .

92. ## math

Hey someone use 192 beads to make a necklace and bracelet it takes 5 times as many beads to make the necklace that the bracelet how much beads it take to make the necklace

93. ## Accounting

T/F Questions The main reason that the bank statement cash balance and the company's cash balance do not initially balance is due to timing differences. Sales Discounts is a revenue account with a credit balance. Multiple Choice: Assuming a 360-day year,

94. ## physics

A light spring with force constant 3.00 N/m is compressed by 6.00 cm as it is held between a 0.350 kg block on the left and a 0.700 kg block on the right, both resting on a horizontal surface. The spring exerts a force on each block, tending to push them

95. ## Chemistry

If 10.0g of Pb at 25.0oC absorbs 1.00kJ of heat, what is it's final temperature?

96. ## Math

a regular plot of land is designed so that its length is 6 meters more than its width. the diagonal of the land is 10 meters. to the nearest tenth of a meter, what are the dimensions of the land?

97. ## chemistry

Knowing the concentration of a solution allows us to find all of the following except A. the mass of a solute. B. the mass of the solvent. C. the volume of the solvent. D. the concentration of a solution when conditions change.

98. ## Physics

You will fire the spring gun 3 times from the first detent and measure the change in height of the (pendulum + ball) for each shot. Write the equation for the change in height of the first shot.

99. ## Chemistry

How much heat is needed to melt a 25 gram ice-cube at 0 °C? The molar heat of fusion for water is 6.01 kJ/mol. A) 6.01 kJ B) 8.35 kJ C) 150.25 kJ D) 3.34 kJ E) 9.22 kJ