# Lance

Popular questions and responses by Lance
1. ## Chemistry

Propane, C3H8, is a common fuel gas. Use the following to calculate the grams of propane you would need to provide 383 kJ of heat. C3H8(g) + 5 O2(g) → 3 CO2(g) + 4 H2O(g) ΔH = −2043 kJ

2. ## bobpursley, drwls. ms. sue Writeacher

When a second post is made to a question, the most recent is now at the bottom. Do any of you prefer the way it was, or do you like this better? I prefer to have the answers shown in the order they were posted. The second answer may clarify or add

3. ## Chemistry

A sample of ethanol, C2H5OH, weighing 2.84 g was burned in an excess of oxygen in a bomb calorimeter. The temperature of the calorimeter rose from 25.00°C to 33.73°C. If the heat capacity of the calorimeter and contents was 9.63 kJ/°C, what is the value

4. ## Phase

http://en.wikipedia.org/wiki/Melting_point Question: A solid substance has a vapor pressure of 100 mmHg at the melting point (100C). Assuming an atmospheric pressure of 760 mmHg, describe the behavior of this solid as the temperature is raised from room

5. ## Physics

A 500-mL beaker has a mass of 250 g when empty and 645 g when filled with an unknown liquid. What is the density of the liquid?

6. ## Math

If f(x)=5x-12, find a value for x so that f^-1(x)=f(x+1). Thank you so much

7. ## Chemistry

Calculate the molar heat of neutralization in kj/mol of the reaction between HA and BOH given the following information: The temperature change equals 9C 50mL of 1M concentration of Acid 50ml of 1M concentration of Base Heat Capacity of the calorimeter is

8. ## Physics

What is the gauge pressure if the absolute pressure is 400 kPa?

9. ## Physics

An object is placed at a distance of 60 cm from a converging lens with a focal length of 20cm. What is the magnification of the lens?

10. ## Physics

What is the absolute pressure 1.8 m below the surface of a lake?

11. ## Physics

What is the absolute pressure if the gauge pressure is 100 kPa?

12. ## Physics (HELP)

An object is placed at a distance of 60 cm from a converging lens with a focal length of 20 cm. What is the magnification of the lens?

13. ## Chemistry

The triation of 50.00 mL of 0.025 00 M MES with 0.100 0 M NaOH. MES is a weak acid with pKa=6.27. Compute Ve, first. Show what happens at the four stages of the titration: Va = 0,2,5,10,10.1,11,12, and 12.2 mL. I NEED HELP!!!!

14. ## Chemistry

For each of the following pairs of elements, state whether the binary compound formed is likely to be ionic or covalent. Give the formula and name of the compound. (a) C, Cl Its covalent, but I get the formula wrong and name wrong,CCl Carbon Chloride.

15. ## psychology

We don't just answer questions here. We help. So at least tell us your best thought out answer and why you chose it. Then we'll help. A truck gets stuck under a bridge. Several tow-trucks are unable to pull it ou. At last a little boy walks up and asks the

16. ## Chemisrty

Where can i find drawing of electron dot stuctures for compounds like BR2 and HCN HCN is at the link below. http://dl.clackamas.edu/ch106-01/formulas.htm I couldn't find one for Br2 on line but here is how it will look.   .. .. :Br:Br:

17. ## Physics

What is the absolute pressure if the gauge pressure is 3.2 atm?

18. ## Physics

What is the mass of a rectangular shaped ice block with dimensions of 0.04m x 0.05m x 0.03m if the density of ice is 917 kg/m3?

19. ## Physics (HELP)

An object inside of the focal point of a concave mirror produces an image that is...

20. ## math

Without doing the computation explain why or why not19.7 is a reasonable value for the expression 122.14÷6.2.

21. ## College Chemistry

A gas containing carbon and hydrogen analyzed as 85.6 % carbon and 14.4 % hydrogen. A 42.1 g sample of a gas occupied a volume of 7490 mL with a pressure of 2280.0 torr at 92 °C. Enter the molecular formula of the compound. Thanks.

22. ## Chemistry

Carbon tetrachloride CCl4 contains carbon (EN = 2.5) and chloride (EN = 3.0). Because of this, CCl4 is:

23. ## SCIENCE

Conservation of natural resources could include- A. the use of more renewable sources of energy B. cutting down on the use of fossil fuels C. replacing soil and planting trees D. all of the above

24. ## Geometry

2. Segment RT is the midsegment of the trapezoid. Find x.

25. ## Chemistry

Assume a piece of hot metal is added to a calorimeter containing 50mL of water at 22C. The amount of heat released by the metal was determined to be 1000J, and the equilibrium temperature in the calorimeter was 26C. Remembering that the specific heat of

26. ## Chemistry

Assume a piece of hot metal is added to a calorimeter containing 50mL of water at 22C. The amount of heat released by the metal was determined to be 1000J, and the equilibrium temperature in the calorimeter was 26C. Remembering that the specific heat of

27. ## Chemistry

(a) A sample of cesium metal reacted completely with water, evolving 48.7 mL of dry H2 at 24°C and 774 mmHg. What is the equation for the reaction? Include states-of-matter under SATP conditions in your answer. Use the lowest possible coefficients. (b)

28. ## Chemistry

A particular microwave oven delivers 800 watts. (A watt is a unit of power, which is the joules of energy delivered, or used, per second.) If the oven uses microwave radiation of wavelength 12.2 cm, how many photons of this radiation are required to heat

29. ## Chemistry

What is the energy of a photon corresponding to radio waves of frequency 1.475 106 /s? I got 9.77e-28 as an answer and its wrong so what is wrong with my calculations.

30. ## Chemistry

At what speed must an electron travel to have a wavelength of 13.6 pm? I got 9.89x10^-15 as the answer and its wrong where did I mess up in my calculations?

31. ## Chemistry

The specific heat of copper metal was determined by putting a piece of the metal weighing 39.4 g in hot water. The quantity of heat absorbed by the metal was calculated to be 47 J from the temperature drop of the water. What was the specific heat of the

33. ## chemistry

Consider the reaction 2Al + 3CuSO4 = Al2(SO4)3 + 3Cu What is the maximum amount of Cu (63.5 g/mol) that could be produced by reacting 20.0 grams of Al (27.0 g/mol) with excess How do i do this?

34. ## algebra

x + 2y = 4 and x - 4y = 8, solve for x

35. ## PHYSICS

A 745i BMW car can brake to a stop in a distance of 122 ft from a speed of 60.0 mi/h. To brake to a stop from a speed of 80.0 mi/h requires a stopping distance of 221 ft. What is the average braking acceleration for the following intervals? Express the

Adding Doubles just means adding the same numberr to itself. Like 2+2=4, 3+3=6, So addind doubles to 18 would be 0+0=0, 1+1=2, 2+2=4, and so forth up to 9+9=18. Maybe this will help you solve the problem. I have a work sheet that has Add Doubles to 18 with

37. ## Chemistry

non-volatile means a liquid that won't evaporate at all. It's not a commomly encountered term because there is usually some evaporation (especially as heat is applied). The usual phrase is "very low volatility". Oil at room temperature or colder fits this

38. ## Chemistry

catalyst: a substance that changes the speed of a chemical reaction without affecting the yield or undergoing permanent chemical change* As you can see NO (nitrogen monoxide) did not undergo a permanent change.

39. ## Physics

A driving bell can withstand a maximum pressure of 2.5 x 10^6 Pa. What maximum depth can the ball reach in seawater?

40. ## Physics

What is the gauge pressure at the bottom of a pool 1.9 m deep?

41. ## Physics

What is the gauge pressure if the absolute pressure is 321 atm?

42. ## Physics

What is the absolute pressure 2.5 m below sea surface?

43. ## Physics

A diver can withstand a maximum pressure of 3x10^5 Pa. What maximum depth can he reach in seawater?

44. ## Physics

A copper cylinder with a cross-sectional area 0.034 m^2 is placed vertically on a tabletop. What is the weight of the cylinder if it exerts an 800 Pa of pressure on the table top?

45. ## Math

If an elliptic race track is 100 yards long and 20 yards wide, then how far apart are the foci?

46. ## Physics

What is the focal length of a lens that has a center of curvature of 18 meters from one of the curves of the lens?

47. ## Physics

What is the focal length if a lens that has a center of curvature 8 meters from one of the curves on the lens?

48. ## Physics (HELP)

An object is placed at a distance of 6 cm from a concave mirror and an image is produced at a distance at a distance of 14 cm from the mirror. What is the focal length?

49. ## Physics

A ray of light perpendicular to a medium produces a refracted ray measuring 45º. * True False

50. ## Physics (HELP)

The critical angle is the angle at which a ray of light is no longer refracted but completely reflected. True or false?

51. ## Physics (HELP)

When light goes from a medium that is less dense to a medium that is more dense, the angle of the refraction is greater than the angle of the incidence

52. ## Physics (HELP)

A real image is usually inverted, but can be upright in special cases. True or false?

53. ## Physics (HELP)

The angle of reflection of a ray of light striking a plane mirror is ½ the angle of incidence. True or False?

54. ## Physics (HELP)

An object is placed at a distance of 25 meters from a concave mirror with a focal length of 20 meters. The image produced is a distance of ___ meters from the mirror.

55. ## Physics (HELP)

An object is placed at a distance of 8 meters from a concave mirror with a focal length of 6 meters. The image produced is a distance of ___ meters from the mirror.

56. ## Physics (HELP)

Jill pulls on a rope to lift a 12 kg pail out of a well, while the clumsy jack watches. For a 10.0 meter segment of the lift, she lifts the bucket straight up at constant speed. How much power is required to complete this task in 5 seconds?

57. ## Calculus- Related rates

A spherical balloon is inflated at the rate of 1 cm^3 per minuter. At the instant when the radius r=1.5, (a.) how fast is the radius increasing? (b.) how fast is the surface area increasing?

58. ## Calculus

The length l of a rectangle is decreasing at the rate of 3cm/sec, while its width w is increasing at the rate of 3cm/sec. Find the rates of change of (1.) the area, (2.) the perimeter, (3.) the length of one diagonal at the instant when l=15 and w=6.

59. ## Physics

A glacier advances at 7 × 10−6 cm/s. How far will it move in 3.7 y? Answer in units of cm. I have calculated that there are 31,449,600 seconds in a year. I multiplied 31,449,600 by 7 × 10−6 and got 2201.472. Then I multiplied that by 3.7 and got

60. ## Chemistry

Sodium + Sulfuric Acid and Phosphoric Acid + Magnesium Hydroxide a.write the formula b. supply the product c.type of reaction d. balancing

61. ## Math

Let f(a,b) = 2a - 3b^2 + 7. If f(b,3) = 90, then what is b? Thank you for helping!

62. ## Math

If 1 < x < 9/8, which is bigger, ∛3x or √2x.

63. ## Math haha

Simplify: ( 7/2+5/6 )^2 - ( 7/2-5/6 )^2

64. ## Math

If 1 > x > 9/8, which is bigger, ∛3x or √2x.

65. ## MATH

I am trying to find the rule for a function table with input 2, output 30; input 3, output 48; input 4, output 66.

66. ## physics

A 78 kg bag of mortar mix is sitting in the back of a truck rounding a traffic circle of radius 27 m at a speed of 21 km/h. Using the truck's frame of reference, find the force of contact between the bag and the side of the truck. Assume that the floor at

67. ## Algebra, Logirithms

Find the inverse of the function: f(x) = e^(4x+2) - 10

68. ## Math

Help Please! The LCM of two numbers is 60. The GCF of the numbers is 5. One number is 5 more than the other. The numbers are________ and __________ Please help clueless in Massachusetts

69. ## math

Brandon and Jacob buy used cars at the same time. Brandon buys a car with 10,000 miles on it. He drives an average of 100 miles a week. The equation that follows can be used to determine how many miles, m, will be on the car after any number of weeks of

70. ## Noun and Adjective Clauses

Amanda bought a prom dress which she considered the most beautiful dress ever made. Adjective clause:Amanda bought a prom dress Word(s) modified:dress

71. ## physics

Find the field produced by a uniformly charged sheet carrying 93pC/cm2 .

72. ## Statistics

The inside diameter of the automobile wheel bearing sets at a factory is expected to be normally distributed with a mean of 1.30inches and a standard deviation of 0.04 inches. What is the probability that a randomly selected wheel bearing will have an

73. ## Physics

Steps for drawing an acceleration time graph from a velocity time graph and vice versa?l Please give me proper steps

74. ## math

Triangle GHI is an isosceles triangle. H is the vertex. If the measure of H is 73 degrees what is the measure of G? A.73 B.17 C.34 D.104 A)73 degrees?

75. ## Math

Triangle ABC is an isosceles triangle If the measure of B is 37 degrees what is the measure of C? A.37 B.53 C.106 D.143 I think it's A or C?

76. ## Science

Why do you think people wrestle alligators?

77. ## English

To assert means to A.put into words forcefully b.pass along stories quickly C.compliment someone often D.explain something completely A?

78. ## English

An incident is a single A. event B.person C.memory D.discussion A?

79. ## Analytic Geometry

A parabola has a directrix y=-3, axis =4 and latus rectum equal to 2. find its equation. Please help me its for my homework

80. ## Analytic Geometry

Find the equation of a circle passing through and tangent to the line x-3y+8=0

81. ## Analytic Geometry

Give the equation of the circle tangent to both axes of radius 5 and in the 1st quadrant. Can you help me solve this?

82. ## Analytic Geometry

What are the equations of the circles tangent to the x-axis, of radius 4 and whose center is at (-2,y) Please help, how do I solve this problem?

83. ## Analytic Geometry

A point is equidistant from (-2,4) and (3,5). It is also equidistant from (-2,-3) and (6,-1). Find the point Please I need Help with this

84. ## Analytic Geometry

A point is equidistant from (-2,4) and (3,5). It is also equidistant from (-2,-3) and (6,-1). Find the point Please I need Help with this

85. ## Geometry

What is the equation of a line through (-2,5) and whose segment intercepted between the axes in the 2nd quadrant is 7sqrt2? Please help me solve this

86. ## Math,Geometry

What are the equations of the lines through (-5,-3) and passing at distance 2sqrt5 from (5,7) Please I really need your help. I do not know how to do this problem.

87. ## Math,Geometry

What are the equations of the lines through (-5,-3) and passing at distance 2sqrt5 from (5,7) Please I really need your help. I do not know how to do this problem.

88. ## geometry

What are the equations of the lines through (-5, -3) and passing at distance 2sqrt5 from (5,7)? This problem is confusing? How do I solve this? Please I need your Help

89. ## English

What's the difference between possessive nouns and possessive pronouns? Are they the same

How do you find out what your grade is on a paper? For example if there is 70 questions and you miss 10 how do you find out what your grade is? Do you subtract 70 and 10 and when you get your answer you divide it by 100?

91. ## Math

A highway construction warning sign blinks on and off. In all, the sign is on for 0.88 of each minuite. For how many seconds is the sign on in 5 minutes?

92. ## Science

Define heat in science terms

93. ## Science

You may have heard "Nothing is Free" explain why this is true

94. ## Math perimeter

How many inches of matting are needed to frame an 8in by 11 in print? 38?

95. ## math

How many inches of matting are needed to frame an 8 in by 11 in print 38in?

96. ## Math

When finding the perimeter you have to add the sides not multiply right? For example a rectangle is 14 width and 29 height would the perimeter be 86in?

97. ## physics

You see an optical illusion of an ever-upward spiral staircase. The climber trudges up and up and never gets anywhere, going in circles instead. Suppose the staircase is provided with a narrow ramp, allowing the tired stair-climber to push a wheelbarrow up

98. ## Maths

Three boys shared some cards. Peter had twice as many cards as Farid. The ratio of the number of cards Peter had to the number of cards Kiran had was 6:5. Farid gave 2/3 of his cards to Peter and the rest to Kiran. How many cards did Kiran have at first if

99. ## Finite Math- help wanted. Super hard!

In a past presidential election, it was estimated that the probability that the Republican candidate would be elected was 2/3, and therefore the probability that the Democratic candidate would be elected was 1/3 (the two Independent candidates were given