Monday

October 20, 2014

October 20, 2014

Total # Posts: 238

**math**

semir, sarah and sung so decided to raise money for a local homeless shelter by working in a local deli. the deli agreed to donate to the shelter a portion of the profits from each meal the three sold. semir sold 3 times as many meals as sarah. sung sold 2 more meals than ...
*October 14, 2014*

**Science/chemisty**

Explain in detail how to prepare 250. mL of a 0.125 M glucose solution. The formula for glucose is C6H12O6.
*October 13, 2014*

**Physics **

A horizontal force, F1 = 85 N, and a force, F2 = 18.4 N acting at an angle of θ to the horizontal, are applied to a block of mass m = 2.1 kg. The coefficient of kinetic friction between the block and the surface is μk = 0.2. The block is moving to the right. A. Solve...
*October 9, 2014*

**Trig**

Two people decide to find the height of an obelisk. They position themselves 25 feet apart in line with, and on the same side of, the obelisk. If they find that the angles of elevation from the ground where they are standing to the top of the obelisk are 65 degrees and 44 ...
*September 10, 2014*

**Chemistry**

Fannie eats a dozen doughnuts every 36 hours. How many doughnut does she eat in a week? I used Dimensional Analysis(which isn't helping at all), but it keeps giving me weird number, like 36 over 2016 or 252 over 2016.
*September 1, 2014*

**Maths**

Thanks for all the help, really appreciate it.
*August 28, 2014*

**Maths**

A circular lily pond is surrounded by a gravel walkway that is 4 m wide. Calculate the area of the walkway if the pond is 12 m in diameter.
*August 28, 2014*

**Math**

A number whose digit in the ten billions place is 5 less than 8
*June 18, 2014*

**Math**

:'(
*May 23, 2014*

**Math**

What are the solutions of the system? y = x2 + 3x – 4 y = 2x + 2 Don't understand
*May 23, 2014*

**Chemistry**

The fluoride ion concentration in a saturated solution of magnesium fluoride, MgF2, is 2.3 10-3 M. Calculate the value for the equilibrium constant.
*May 5, 2014*

**Chemistry**

Aniline, C6H5NH2, is a weak base. If the hydroxide ion concentration of a 0.201 M solution is 9.2 10-6 M, what is the ionization constant for the base?
*May 5, 2014*

**Chemistry**

Ah got it now thank you!
*May 1, 2014*

**Chemistry**

Where does the 6.4 come from? 0.784 = 5 over x then you divide 0.784 by 5? I don't quite understand sorry!
*May 1, 2014*

**Chemistry**

Calculate the grams of NaNO3 required to produce 5L of oxygen at STP if the percent yield of the reaction is 78.4%?
*May 1, 2014*

**Chemistry**

I am very confused. I tried several practice problems and am not getting them correct.
*March 26, 2014*

**Chemistry**

What is the mass if solute dissolved in the indicated volume of each of the following solutions? (b) 4.25 L of 0.450 M KIO4g (c) 60.0 mL of 0.310 M ZnSO4g (d) 60.0 mL of 0.310 M Ni(NO3)2g
*March 26, 2014*

**Chemistry**

A hospital saline solution is analyzed to confirm its concentration. A 60.0 mL sample with a mass of 50.443 g is evaporated to dryness. (a) If the solid sodium chloride residue has a mass of 0.413 g, find the mass/mass percent concentration of the NaCl solution. % (b) Find the...
*March 26, 2014*

**Linear Algebra**

I need help please!! How many solutions does the system of equations have? 2x=-10y+6 and x+5y=3 a. one b. two c. infinitely many d. none y=4x+3 and y=4x+4 a. one b. two c. infinitely many d. none x-4y=12 and y=1/4x-3 a. one b. two c. infinitely many d. none
*March 13, 2014*

**Chemistry **

Ik this has been answered, but doesn't the copper oxide have something to do with it? And could you explain it in simpler terms? I'm just confused because you said forget the copper oxide, but your using it somehow, what puzzles me is the carbon dioxide, because the ...
*February 23, 2014*

**Science**

Copper Oxide + Carbon -> Copper + Carbon Dioxide Calculate the mass of carbon needed to obtain 63.5g of copper from 79.5g of Copper Oxide
*February 23, 2014*

**Science**

Copper Oxide + Carbon -> Copper + Carbon Dioxide Calculate the mass of carbon needed to obtain 63.5g of copper from 79.5g of Copper Oxide
*February 23, 2014*

**physics**

A 475 gram box is given a push and it then slides up and back down a ramp with a 35.0° incline. The coefficient of friction is 0.30. (a) Determine the rate of deceleration as the box slides up the ramp. (b) Determine the rate of acceleration as the box slides back down ...
*February 20, 2014*

**Physics **

Find the net force and the acceleration for the situation below. 30N 20N <---------------[ 5.1kg]---------->
*February 19, 2014*

**Chemistry**

This answer is not correct
*February 14, 2014*

**Chemistry**

A sample of oxygen gas occupies 500.0 mL at -185°C and 75.0 cmHg. Calculate the temperature in °C if the gas has a volume of 221.0 mL at a 55.0 cmHg.
*February 14, 2014*

**Chemistry**

A sample of gas has a volume of 1.30 L at STP. What is the temperature in °C if the volume is 13.0 L at 2.00 atm?
*February 14, 2014*

**chemistry**

If the surface area of a human body is 16,700 square centimeters, what is the total weight of the atmosphere on a human body expressed in pounds?
*February 13, 2014*

**chemistry**

Calculate the final Celsius temperature of sulfur dioxide if 0.500 L of the gas at 35°C and 650 mmHg is heated until the pressure reaches 742 mmHg. Assume the volume remains 0.500 L.
*February 13, 2014*

**Ap chem**

Thanks
*February 12, 2014*

**Ap chem**

Why does pf3 have dipole dipole internolecular forces? I thought it had dispersion...
*February 12, 2014*

**algebra**

Mike needs at least a 75% average to pass his math course. The class contains 5 exams that are equally weighted. If he scored a 64%, 86%, 71%, and a 90% on the first 4 exams, what score does he need on the final exam to earn at least a 75% in the class?
*February 2, 2014*

**Algebra**

Martin sold his computer and software for $900.00, receiving three times as much for the computer then the software. What was the selling price of the computer and software?
*February 2, 2014*

**Chemistry**

N2(g) + O2(g) → N2O5(g) What volume of oxygen gas reacts to yield 750.0 cm3 of N2O5? The reaction conditions are 350°C and 2.50 atm pressure. 2N2 + 5 O2 = 2N2O5 I balanced correctly. What is my next step to solve this problem. I am confused and I want to understand ...
*February 2, 2014*

**Chemistry**

N2(g) + O2(g) → N2O5(g) What volume of oxygen gas reacts to yield 750.0 cm3 of N2O5? The reaction conditions are 350°C and 2.50 atm pressure. I balanced the equation 2N2+2O2 = 2N2O5 BUT I AM NOT GETTING THE CORRECT ANSWER, WHAT AM I DOING WRONG?
*February 2, 2014*

**Chemistry**

N2(g) + O2(g) → N2O5(g) What volume of oxygen gas reacts to yield 750.0 cm3 of N2O5? The reaction conditions are 350°C and 2.50 atm pressure. I balanced the equation 2N2+2O2 = 2N2O5 BUT I AM NOT GETTING THE CORRECT ANSWER, WHAT AM I DOING WRONG?
*February 2, 2014*

**Chemistry**

N2(g) + O2(g) → N2O5(g) What volume of oxygen gas reacts to yield 750.0 cm3 of N2O5? The reaction conditions are 350°C and 2.50 atm pressure
*February 2, 2014*

**Chemistry**

SO2(g) + O2(g) → SO3(g) What volume of sulfur dioxide gas reacts with 15.0 L of O2? The reaction conditions are 875°C and 1.00 atm pressure
*February 2, 2014*

**algebra**

The perimeter of a pool is 64 feet and has a width of x and a length of x-4. What is both the width and length of the pool?
*January 24, 2014*

**math**

19 cars start a race. in how many ways can the top 3 cars finish
*December 14, 2013*

**physics**

A small coin is inside a bowl. The bowl is a surface of revolution of the curve y=100x^4 m^-3. This coin slides around the inside of the bowl at a constant height of y=0.01 m above the bottom of the bowl. What is its angular velocity in rad/s? Accel due to gravity = 9.8 m/s^2
*June 24, 2013*

**please hurry**

what is the square root of 0.31428 with explanation.by divison method.
*May 20, 2013*

**Calculus**

Find the derivative
*May 1, 2013*

**Calculus**

f(x)= e−(5x)⋅cos(3x)
*May 1, 2013*

**calculus**

find the solution: (y^(2) dx)/(1-x)=dy
*April 11, 2013*

**calculus**

find the solution: e^y=1/(y^'+1)
*April 11, 2013*

**calculus**

Find the specified coordinates of the centroid of the area bounded by a) x=3 and 2x=y^2 find the coordinates x and y of the centroid b) y= x^3 and y=4x in the first quadrant. Find the x coordinate of the centroid
*April 11, 2013*

**calculus**

Find the coordinates of the centroid of the following volume of revolution formed by rotating the area bounded by y^2-4=-x^2, x=0,x=1, And the "x" axis about the "x" axis.
*April 11, 2013*

**calculus**

Find the particular solution of the following differential equation by using the given boundary conditions. y(1+x)=x(y+1)(dy/dx) when y=1 x=1
*April 11, 2013*

**calculus**

Find the centroid of 4 particles of equal mass located at (0,0), (4,2), (3,-5), and (-2,-3)
*April 11, 2013*

**Math**

please help!!!!Apply newtons method to approximate the x-values of the indicated points of intersection of the 2 graphs. continue the process until 2 successive approximations differ by less than 0.001. (Hint: Let h(x)=f(x)-g(x)) f(x)=x^6 g(x)=cos(x) 1)x= ??? (smaller value) 2...
*April 5, 2013*

**chemistry**

enthalpy change^H is +23kJ mol-1 of phosphine (PH3) for the reaction 2P(s)red+3H2(g)---->2PH3(g) a) Calc. entropy change for this reaction. Explain how this information allows you to determine the spontaneity or non-spontaneity of this reaction at any temp (S for PH3 is ...
*February 12, 2013*

**chemistry**

a gas sample heated in a cylinder uses 650kJ of heat. a piston that compresses this gas does 800kJ of work. What is the change in internal energy, ^E of the gas during this process?
*February 12, 2013*

**chemistry**

list the following substances in order of increasing molar entropy at 25'c. H2O(l), H2O(g), H2O(s), C(s), Ar (g) Explain your reasoning
*February 12, 2013*

**chemistry**

the standard free energies of formation of SO2(g) and SO3(g) are -300.4 and -370.4kJ mol-1 respectively. Calculate the value of the equilibrium constant at 25'C for the reaction 2SO2(g)+O2(g)==>2SO3(g)
*February 12, 2013*

**writing**

I need help to write a summery for the open univercity please write for me one Thanks
*February 7, 2013*

**science**

Which is the higher density of polyethylene, linear or branched? Select the choice with the best accompanying explanation
*January 12, 2013*

**science**

A pressure vessel contains a large volume of CO2 gas at 10 atm pressure. A membrane composed of a poly(ether ketone) polymer with thickness 100 microns and net effective area of 100 cm2 covers a small perforated port in the container. The solubility of CO2 at 10 atm is 6.97 x ...
*January 12, 2013*

**science**

What is the degree of polymerization, n, of polypropylene with a molecular weight of 600,000 g/mole?
*January 12, 2013*

**science**

Calculate the surface energy of the (100) surface of niobium. The enthalpy of atomization of niobium is 745 kJ/mole. Express your answer in units of J/cm2.
*January 12, 2013*

**science**

What is the pH of 50 mL of a 0.2M glycolic acid aqueous solution after adding 5 mL of 0.25 M KOH? The pKa of glycolic acis is 3.83 at 25 .
*January 12, 2013*

**science**

Estimate the Cl-As-F bond angle
*January 12, 2013*

**TO: MS SUE MATH 9**

ok :)
*December 13, 2012*

**TO: MS SUE MATH 9**

thank you for trying and hopefully its right :)
*December 13, 2012*

**TO: MS SUE MATH 9**

The cube of the sum of 5 an 2 is decreased by the square of the product of 6 and 4. Write an expression that models this statement. Then , solve. THANX
*December 13, 2012*

**Math 9 pleese help me thanx**

The cube of the sum of 5 an 2 is decreased by the square of the product of 6 and 4. Write an expression that models this statement. Then , solve.
*December 13, 2012*

**Physics**

A force of 40 N is required to start a 5 kg box moving across a horizontal concrete floor. (a) What is the coefficient of static friction between the box and the floor? (b) If the 40 N force continues, the box accelerates at 0.70 m/s2. What is the coefficient of kinetic friction?
*December 4, 2012*

**AP chemistry**

Liquid butane, C4H10, is stored in cylinders, to be used as a fuel. The normal boiling point of butane is listed as -0.5 C. (a) suppose the tank is standing in the sun and reaches a temperature of 35 C. Would you expect the pressure in the tank to be greater or less than ...
*October 28, 2012*

**ap chemistry help!!!!**

Ive been absent from class because of the flu so i don't have a clue how to figure these out! Help! due tomorrow at 12! 1).Suppose that 135 g of ethanol at 23◦C is mixed with 255 g of ethanol at 75◦C at constant atmospheric pressure in a thermally insulated ...
*October 24, 2012*

**Math**

Which coins would you use to make $0.28? Write two ways
*October 1, 2012*

**Math**

Write the number that is 2 tens more than 53.
*October 1, 2012*

**physics**

200 gram cube is moved by a 100 gram water filled Styrofoam cup
*September 20, 2012*

**Math **

A pet store has 15 rabbits and 25 cats. How many more cats than rabbits does the store have?
*September 19, 2012*

**Math**

Write a4-digit number that has a hundrens digit of 6, a tens digit of 3, and 9 for each of the other digits.
*September 19, 2012*

**college calc**

Give a formula for the function illustrated using a vertical shift of an exponential function. The two points marked on the graph are A=(−1,17) and B=(1,2). The red horizontal line is given by y=1, and is a horizontal asymptote of the function. What is the equation?
*September 6, 2012*

**math**

y = x2 + 6x
*July 26, 2012*

**math HELP HELP HELP**

Hi, I am 12 years experienced tutor and assignment helper for computer science. I am ready to get this assignment done for you but you have to pay fee for it.For further discussion email me at hardeepsp ( at the rate) gmail (dot)com or contact me in skype or gtalk. my skype is...
*April 30, 2012*

**Programming logic**

Hi, I am 12 years experienced tutor and assignment helper for computer science. I am ready to get this assignment done for you but you have to pay fee for it.For further discussion email me at hardeepsp ( at the rate) gmail (dot)com or contact me in skype or gtalk. my skype is...
*April 30, 2012*

**python programming**

Hi, I am 12 years experienced tutor and assignment helper for computer science. I am ready to get this assignment done for you but you have to pay fee for it.For further discussion email me at hardeepsp ( at the rate) gmail (dot)com or contact me in skype or gtalk. my skype is...
*April 29, 2012*

**programming**

Hi, I am 12 years experienced tutor and assignment helper for computer science. I am ready to get this assignment done for you but you have to pay fee for it.For further discussion email me at hardeepsp ( at the rate) gmail (dot)com or contact me in skype or gtalk. my skype is...
*April 25, 2012*

**Math**

Find the value of csc Q for angle Q in standard position if the point at (3, –1) lies on its terminal side.
*April 10, 2012*

**c++programming**

Hi, I am 12 years experienced tutor and assignment helper for computer science. I am ready to get this assignment done for you but you have to pay fee for it.For further discussion email me at hardeepsp ( at the rate) gmail (dot)com or contact me in skype or gtalk. my skype is...
*April 10, 2012*

**Chemistry**

One enzyme- catalyzed reaction in a biochemical cycle has an equilibrium constant (K1) that is 10 times the equilibrium constant (K2) of a second reaction. If the standard Gibbs energy of the former reaction is - 300 kJ mol-1, what is the standard reaction Gibbs energy of the ...
*April 10, 2012*

**phys chem**

Calculate the Coulomb potential due to the nuclei at a point in a LiH molecule located 200 pm from the Li nucleus and 150 pm from the H nucleus. just doing exam review and got stuck on just this one, be great if I could get an answer.
*April 9, 2012*

**Science**

they could set up a bunjee jump and charge ten bucks for it
*April 9, 2012*

**math**

51 one data points with an average of 3.04 meaning you could assume every data point is 3.04. Multiply that by the 51 entries, add 16 to that number then divide by 52
*April 9, 2012*

**Simple Interest**

compound or simple intrest? earn 74000 or get account from 45000 to 74000?
*April 9, 2012*

**math**

5x2=10 7x2=14 +1 =25?
*April 9, 2012*

**math**

ya obviously you could save 82 bucks if you won
*April 9, 2012*

**Chemistry**

Uranium-238 has half life of 4.51 * 10^9 years Uranium-234 has half life of 2.48 * 10^5 years Thorium-230 has half life of 8.0 * 10^4 years Radium-226 has half life of 1.62 * 10^3 years Lead-210 has half life of 20.4 years. The rate constant for the decay of unstable nuclide X...
*March 20, 2012*

**Chemistry**

What volume will be required to contain a mixture of 0.547 mol of N2 and 0.547 mol of O2 at 1.11 atm and 22.1 degrees celsius?
*March 20, 2012*

**Math**

An alien rocketship is traveling at a speed of 2,500,000 feet per minute. At this speed, how many miles will it travel in 1 second? Round to the nearest thousandth.
*February 20, 2012*

**Math**

Transform: log3^4= log(3/4)=
*February 20, 2012*

**physics**

A 690 kg elevator starts from rest. It moves upward for 2.56 s with constant acceleration until it reaches its cruising speed, 1.84 m/s. What is the average power of the elevator motor during this period? What is the power of the elevator motor during an upward cruise with ...
*February 20, 2012*

**physics**

A 67.7 kg person jumps from rest off a 3.11 m-high tower straight down into the water. Neglect air resistance during the descent. She comes to rest 1.04 m under the surface of the water. Determine the magnitude of the average force that the water exerts on the diver. This ...
*February 19, 2012*

**physics**

A basketball player makes a jump shot. The 0.585 kg ball is released at a height of 2.14 m above the floor with a speed of 7.15 m/s. The ball goes through the net 3.10 m above the floor at a speed of 4.19 m/s. What is the work done on the ball by air resistance, a ...
*February 19, 2012*

**MATH**

does 2+2-2+2-2+2-2-2+2=2 ??
*February 15, 2012*

**is this correct?- math**

thank you very much!
*February 12, 2012*

**is this correct?- math**

find the domain of the real valued function; f(x) = sqrt(5 - (sqrtx)) my solution: 5 - (sqrt x) >=0 -(sqrt x) >= -5 (sqrt x) <= 5 x <= 25 (-infinity, 25] is this correct?
*February 12, 2012*

**math**

1.) The first person who requires your assistance is Tina the bearded lady. Tina’s side job is to look after the elephants (she double majored at circus university.) a. Tina must fill the semi-circular trough shown above with peanuts. Tina knows that the store bought ...
*February 11, 2012*