Friday
February 5, 2016

# Posts by bill

Total # Posts: 788

Chemistry
2.05 g of an unknown gas at 45 °C and 1.00 atm is stored in a 1.15-L flask. What is the density of the gas?
October 16, 2012

Chemistry
At a certain temperature and pressure, one liter of CO2 gas weighs 1.45 g. What is the mass of one liter of C4H10 gas at the same temperature and pressure?
October 16, 2012

Chemistry
October 16, 2012

Chemistry
A hot air balloon is filled with 1.39 × 106 L of an ideal gas on a cool morning (11 °C). The air is heated to 105 °C. What is the volume of the air in the balloon after it is heated? Assume that none of the gas escapes from the balloon.
October 16, 2012

Chemistry
An ideal gas is allowed to expand from 6.00 L to 45.0 L at constant temperature. By what factor does the volume increase? ? Number The pressure will Increase by that factor or decrease by that factor? If the initial pressure was 105 atm, what is the final pressure?
October 16, 2012

Math HELPPP
In a survey of 2000 adults 50 years and older of whom 40% were retired and 60% were pre-retired, the following question was asked: Do you expect your income needs to vary from year to year in retirement? Of those who were retired, 33% answered no, and 67% answered yes. Of ...
October 16, 2012

Calculus
What is the derivative of 7e^(3sin^(4x+5))?
October 16, 2012

Calculus
What is the derivative of 2^(5x)tan(x^2)
October 16, 2012

Calculus
What is the derivative of sin(3x+1)^4?
October 15, 2012

Calculus
Find dy/dx using implicit differentiation of xy + sin^2y=10350. Is it -y/(x+2siny)
October 15, 2012

Calculus
Dervative of cos(x) is -sin(x) so it would be negative.
October 15, 2012

Math
How do you solve this equation; There are 128 7th graders at Mark's school, if there are 16 more girls than boys, how many 7th grade boys are there?
October 13, 2012

Physics
From the window of a building, a ball is tossed from a height y0 above the ground with an initial velocity of 9.40 m/s and angle of 23.0° below the horizontal. It strikes the ground 5.00 s later. By how much does the ball clear or fall short (vertically) of clearing the ...
October 12, 2012

Physics
From the window of a building, a ball is tossed from a height y0 above the ground with an initial velocity of 9.40 m/s and angle of 23.0° below the horizontal. It strikes the ground 5.00 s later. By how much does the ball clear or fall short (vertically) of clearing the ...
October 12, 2012

writing (persuasive essay)
Hi. I'm in 10th grade and our teacher assigned us a persuasive essay to write in class over a topic that we debated about for the last two weeks. Every team had a different topics (mine was school should start from 11 am. to 5 pm), but now we're going to write a ...
October 7, 2012

math
write 718.5 in scientific notation
October 6, 2012

Physics
A swimmer, capable of swimming at a speed of 0.8 m/s in still water (i.e., the swimmer can swim with a speed of 0.8 m/s relative to the water), starts to swim directly across a 2.5 km wide river. However, the current is 0.91 m/s, and it carries the swimmer downstream.
September 25, 2012

the answer is 15 because nothing inside the lines can be negitive
September 23, 2012

english
what word do these letters make
September 18, 2012

algebra
a rectangle has a length of 17 inches more than twice its height. If the perimeter of a rectangle is 304 inches, find its dimensions.
September 15, 2012

Computers
double **dptr; dptr = new double*[5]; for (int i = 0; i < 5; i++) dptr[i] = new double[3]; How many rows and columns will there be in dptr? Also, what would the code look like to Delete all the space allocated for dptr???
August 31, 2012

geometry
If EF=10x+12,FG=14,and EG=136, find the value of x.
August 29, 2012

world literature
July 25, 2012

chemistry
An ice cube of mass 10g at -10C is added to the beaker containing 150mL of water at 88.5C. Assuming no heat is lost to the surrounding; calculate the equilibrium temperature for the liquid after the ice melts.(Heat of fusion for H2O = 6.01 kJ/mol. Heat of vaporization 40.67kJ/...
June 21, 2012

chemistry
What volume of LR(Lactated Ringer's) solution would be required to make 1.0L of a solution that was .050M in chloride ion?
June 12, 2012

Math
The state of texas covers approxmiately 268,581 squared mi. During a hail storm the entire state is covered in 1billion meters of hail.(average radius of 1.4292cm)assume the hail falls so that the gaps of air are limited to 26% of the volume. As the state begins to warm, the ...
June 7, 2012

chemistry
268,581*** squared miles
June 6, 2012

chemistry
The state of texas covers approxmiately 268,58 squared mi. During a hail storm the entire state is covered in 1billion meters of hail.(average radius of 1.4292cm)assume the hail falls so that the gaps of air are limited to 26% of the volume. As the state begins to warm, the ...
June 6, 2012

Physics
Awesome, thanks Elena!
May 31, 2012

Physics
Calculate the force on an electron (qe = -1.6 x 10^-19 C) in each of the following situations: a.) moving at 2.0% the speed of light and perpendicular to a 3.0 T magnetic field b.) 3.0 x 10^-6 m from a proton c.) in Earth's gravitational field at the surface of Earth
May 31, 2012

Physics
oops accidentally posted twice... sorry.
May 31, 2012

Physics
Calculate the force on an electron (qe = -1.6 x 10-19 C) in each of the following situations: a.) moving at 2.0% the speed of light and perpendicular to a 3.0 T magnetic field b.) 3.0 x 10-6 m from a proton c.) in Earth's gravitational field at the surface of Earth
May 31, 2012

math
An object travelling in a straight line away from a motion sensor at a constant rate moves from 4 m away to 16 m away between t = 1 s and t = 6 s. Describe the segment corresponding to this walk on the speed versus time graph.
May 30, 2012

math
(2,-7) is a point on the graph of y=f(x) . Find the corresponding point on the graph of y= 3f(5(x-1)+1 .
May 30, 2012

chemistry
A sample of a saturated hydrocarbon is placed in a 1.0L vessel at 107oC. The pressure of the sample at these conditions is .40 atm. A stoichiometrically equivalent amount of oxygen is added to the vessel and the mixture is combusted. Following combustion, the pressure in the ...
May 22, 2012

chemistry
it isn't showing your response in the earlier post!
May 22, 2012

chemistry
A 20.0 gram sample is a mixture of sodium phosphate ,sodium mono-hydrogen phosphate,sodium dihydrogen phosphate and sodium chloride. The sample is dissolved in 100.0 ml of deionized water and titrated with 1.5 M hydrochloric acid. The initial pH of the solution is pH= 12.9. ...
May 22, 2012

chemistry
A 20.0 gram sample is a mixture of sodium phosphate ,sodium mono-hydrogen phosphate,sodium dihydrogen phosphate and sodium chloride. The sample is dissolved in 100.0 ml of deionized water and titrated with 1.5 M hydrochloric acid. The initial pH of the solution is pH= 12.9. ...
May 22, 2012

Honors Chemistry
This is a few of my final review questions. I basically just need to know the steps for each one because my teacher doesn't explain them very well. I would really appreciate some help.
May 21, 2012

Honors Chemistry
1. .0025 M tartaric acid completely reacts with .0030 M of Al bicarbonate if .913 l of CO2 forms at 298 Kelvin with pressure of 1.4 ATM how much base used? 2. 3.1 x 10^23 molecules of .0035 M hydriodic acid reacts with 25 grams of magnesium bicarbonate how much carbon dioxide ...
May 21, 2012

math
m=4;(3,2)
May 10, 2012

math
Managers should consider ethical aspects of their decisions because:
May 5, 2012

chemistry
heeeeellppppppp
May 4, 2012

algebra
x^2 +4x +9y^2 -36y +4=0
April 29, 2012

math
v=lwh
April 26, 2012

math
1. x^2 + y^2 = 20 x+y=6 2. y=x^2-2x+1 y-3=x How would I go about solving these?
April 26, 2012

chemistry
need formula to this. Carbon monoxide reacts with oxygen to produce carbon dioxide. If 3.0 Liters of carbon monoxide at STP, how many liters of oxygen are required to run the reaction
April 16, 2012

physics - college
i think their is a mistake, the answer is incorrect
April 15, 2012

physics - college
An unmarked police car traveling a constant 95km/h is passed by a speeder traveling 14km/h .Precisely 2.50s after the speeder passes, the police officer steps on the accelerator; if the police car's acceleration is 2.30m/s^2 , how much time passes before the police car ...
April 15, 2012

physics - college
An unmarked police car traveling a constant 95km/h is passed by a speeder traveling 14km/h .Precisely 2.50s after the speeder passes, the police officer steps on the accelerator; if the police car's acceleration is 2.30m/s^2 , how much time passes before the police car ...
April 15, 2012

chemistry
The formate ion, (CHO2-), is related to the acetate ion and forms ionic salts with many metal ions. Assume that 9.7416 g of M(CHO2)2 (where M represents the atomic symbol for a particular metal) are dissolved in water. When a solution of 0.200 M sodium sulfate is added, a ...
April 11, 2012

chemistry
The formate ion, (CHO2-), is related to the acetate ion and forms ionic salts with many metal ions. Assume that 9.7416 g of M(CHO2)2 (where M represents the atomic symbol for a particular metal) are dissolved in water. When a solution of 0.200 M sodium sulfate is added, a ...
April 11, 2012

english
April 5, 2012

Math
Tonya took out a loan to help pay for her house. She borrowed \$50,000 for 15 years at a yearly simple interest rate of 5%. How much interest will she end up paying the bank?
April 4, 2012

biology
Its A, Mario is wrong
March 21, 2012

Algebra
If you have a rectangle and increase the length by 20% while decreasing the with by 20% what is the change equated at?
March 21, 2012

calculus
Find the first derivative for, (e^(x)+ e^(-x))^2
March 4, 2012

Physics
Because of the Earth's rotation, a plumb bob does not hang exactly along a line directed to the center of the Earth. How much does the plumb bob deviate from a radial line at 35.1° north latitude? Assume the Earth is spherical.
February 25, 2012

calculus
how did you find f(x)? i didn't know how to do it??
February 25, 2012

calculus
umm..i don't really know i i didn't know how to do it.. i don't even think i need that part anyway.....and i checked my work and it was x=4 not -4
February 25, 2012

calculus
Consider a differentiable functionf having domain all positive real numbers, and for which it is known that f'(x)=(4-x)^-3 for x.0 a. find the x-coordinate of the critical point f. DEtermine whether the point is a relative maximum or minomum, or neither for the fxn f. ...
February 25, 2012

statistics
Five independent samples, each of size n, are to be drawn from a normal distribution where sigma is known. For each sample, the interval (y-bar - 0.96 * sigma/sqrt(n), y-bar + 1.06 *sigma/sqrt(n)) will be constructed. What is the probability that at least four of the intervals...
February 12, 2012

AP Chemistry
Thank You
February 7, 2012

AP Chemistry
In the titration of 77.5 mL of 1.0 M methylamine, CH3NH2 (Kb = 4.4 10-4), with 0.38 M HCl, calculate the pH under the following conditions. (a) after 50.0 mL of 0.38 M HCl has been added (b) at the stoichiometric point
February 7, 2012

AP Chemistry
Thank you very much.
February 7, 2012

AP Chemistry
Consider 67.0 mL of a solution of weak acid HA (Ka = 1.00 10-6), which has a pH of 4.500. What volume of water must be added to make the pH = 5.000?
February 7, 2012

On finding the proper correct answer. It's easier too First read test booklet. The answers will most of the time will be there.( Note I was only checking meanings ver's difinations with booklet & Google Online for proper choice.) Business Management as far being ...
January 30, 2012

accounting
E4-19 On December 31, the adjusted trial balance of Oslo Employment Agency shows the following selected data. Accounts Receivable \$24,000 Commission Revenue \$92,000 Interest Expense 7,800 Interest Payable 1,500 Analysis shows that adjusting entries were made to (1) accrue \$4,...
January 26, 2012

Sceince
which of the following effects would also occur at the end of an Ice Age 1.) an increase in volcanic activity near the equator. 2.) a global rise in the sea level. 3.) a worldwide extinction of the reptiles. 4.)a shorte length of the day. 5.)a complete rearrangement of the ...
January 13, 2012

AP Chem
At a particular temperature, Kp = 0.25 for the following reaction. N2O4(g) 2 NO2(g) (a) A flask containing only N2O4 at an initial pressure of 5.3 atm is allowed to reach equilibrium. Calculate the equilibrium partial pressures of the gases. (b) A flask containing only NO2 at ...
January 8, 2012

AP Chem
At a particular temperature, K = 1.00 102 for the following reaction. H2(g) + I2(g) 2 HI(g) In an experiment, 1.23 mol H2, 1.23 mol I2, and 1.23 mol HI are introduced into a 1.00 L container. Calculate the concentrations of all species when equilibrium is reached.
January 8, 2012

AP Chem
At a particular temperature, K = 3.75 for the following reaction. SO2(g) + NO2(g) SO3(g) + NO(g) If all four gases had initial concentrations of 0.580 M, calculate the equilibrium concentrations of the gases.
January 8, 2012

AP Chem
At a certain temperature, 4.0 mol NH3 is introduced into a 2.0 L container, and the NH3 partially dissociates by the reaction. 2 NH3(g) N2(g) + 3 H2(g) At equilibrium, 2.0 mol NH3 remains. What is the value of K for this reaction?
January 8, 2012

AP Chem
The following reaction has Kp = 109 at 25°C. 2 NO(g) + Br2(g) 2 NOBr(g) If the equilibrium partial pressure of Br2 is 0.0159 atm and the equilibrium partial pressure of NOBr is 0.0768 atm, calculate the partial pressure of NO at equilibrium.
January 8, 2012

math
Today only a table is sold at a 28% discount. the sale price is now 666. what was the price yesterday?
January 8, 2012

Pysics
60*10=600m/s/s
January 5, 2012

Question
You take the SAT in 11th grade....
December 30, 2011

algebra
popcorn
December 19, 2011

Calculus
At 4 PM ship A is 40 miles due South Ship B. Ship A is sailing due South at a rate of 20 knots while ship B is sailing due East at a rate of 25 knots. Find the rate of change of the distance between the ships at 3 PM and at 5 PM. At what time were the ships closest together...
December 12, 2011

AP Chemistry
A solution is prepared by mixing 50.0 mL of 0.17 M Pb(NO3)2 with 50.0 mL of 1.6 M KCl. Calculate the concentrations of Pb2+ and Cl - at equilibrium. Ksp for PbCl2(s) is 1.6X 10-5.
December 4, 2011

AP Chemistry
Will a precipitate form when 100.0 mL of a 7.5 10-4 M Mg(NO3)2 is added to 100.0 mL of 5.8 10-4 M NaOH? (Hint: Ksp for Mg(OH)2 = 8.9 10-12) Give the value of Q, to support your answer.
December 4, 2011

AP Chemistry
The solubility of solid Ce(IO3)3 in a 0.20 M KIO3 solution is 4.4 10-8 mol/L. Calculate Ksp.
December 4, 2011

AP Chem
The Ksp for silver sulfate (Ag2SO4) is 1.2 10-5. Calculate the solubility of silver sulfate in each of the following. 0.30 M K2SO4
December 4, 2011

What are the three elements of customer service, and how are they important to CRM?. * CRM is (customer relationship management)*
December 3, 2011

physics
What is the total force on the bottom of a swimming pool 20.5 m by 8.0 m whose uniform depth is 2.1 m?
November 29, 2011

algebra
if mary takes 3 hours to mow a lawn and sally takes 5 hours how long will it take them to mow it together
November 14, 2011

Chemistry
The combustion of 0.1583 g benzoic acid increases the temperature of a bomb calorimeter by 2.93°C. Calculate the heat capacity of this calorimeter. (The energy released by combustion of benzoic acid is 26.42 kJ/g.) A 0.1710 g sample of vanillin (C8H8O3) is then burned in ...
November 13, 2011

Chemistry
Consider the following reaction. CH4(g) + 2 O2(g) CO2(g) + 2 H2O(l) ÄH = -891 kJ Calculate the enthalpy change for each of the following cases. 1.00 103 L methane gas at 719 torr and 26°C is burned in excess oxygen.
November 13, 2011

Chemistry
Consider the dissolution of CaCl2. CaCl2(s) Ca2+(aq) + 2 Cl-(aq) ÄH = -81.5 kJ A 12.4 g sample of CaCl2 is dissolved in 100. g of water, with both substances at 25.0°C. Calculate the final temperature of the solution assuming no heat lost to the surroundings and ...
November 13, 2011

Chemistry
A 5.00-g sample of aluminum pellets (specific heat capacity = 0.89 J/°C · g) and a 10.00-g sample of iron pellets (specific heat capacity = 0.45 J/°C · g) are heated to 100.0°C. The mixture of hot iron and aluminum is then dropped into 91.9 g of water...
November 13, 2011

chemistry
-4.1 KJ
November 13, 2011

chemistry
The enthalpy of neutralization for the reaction of a strong acid with a strong base is -56 kJ/mol of water produced. How much energy will be released when 185.0 mL of 0.400 M HCl is mixed with 152.5 mL of 0.500 M NaOH?
November 13, 2011

physics
If it requires 5.5 J of work to stretch a particular spring by 2.0 cm from its equilibrium length, how much more work will be required to stretch it an additional 4.1 cm?
November 12, 2011

algebra
Multiply , then simplify 5 sqrt:75 - 7 sqrt:3
November 9, 2011

algebra
solve (x+17)(x-6)(x+14)>0
November 8, 2011

math
In the bac of an old cupboard you discover a note signed by a pirate famous for his bizarre sense of humor and love of logical puzzles. In the note he wrote that he had hidden treasure somewhere on the property. He listed five true statements and challenged the reader to use ...
November 4, 2011

Chemistry
How much by mass of Urea (NH2)2CO is required for a 32.5% solution in one litre of water.
October 24, 2011

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