Thursday

May 5, 2016
Total # Posts: 890

**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)?
*April 11, 2016*

**Math**

Four people want to cross a bridge. They all begin on the same side. It’s night time and they only have one flash light with them. At most two people can cross the bridge at the same time, and any party who crosses, either one or two people must have a flashlight with ...
*March 18, 2016*

**Math**

Tommy has 5 jars. Each jar is 2/3 filled with marbles. How many full jars of marbles does tommy have ?
*March 17, 2016*

**math**

if an invoice is dated april 25 and has credit terms of 3/15 ,n/45 , what is the last date on which the net amount of the invoice can be paid without incurring an penalty
*March 13, 2016*

**Math **

Find the circumference of 15in and round your answer to the nearest tenth
*February 26, 2016*

**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?
*December 6, 2015*

**Chemistry**

Find the volume of 0.250M sulfuric acid necessary to react completely with 79.3g sodium hydroxide
*November 28, 2015*

**English**

Ok I think I got it. The complete subject is taking the exam
*November 19, 2015*

**English**

Taking is the verb
*November 19, 2015*

**English**

there is the verb. helping verb is was am I close?
*November 19, 2015*

**English**

taking the exam
*November 19, 2015*

**English**

Please check my answer There was one student still taking the exam when the bell rang. Student is the subject and exam is the simple subject.
*November 19, 2015*

**Chemistry**

Thank you!
*October 29, 2015*

**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 mass of Fe(OH)3...
*October 29, 2015*

**Chemistry**

Identify the excess reactant (HCl or NaOH) and its molar concentration when 1.55 g of NaOH is stirred into 150.0 mL of 0.250 M HCl.
*October 28, 2015*

**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 0.242 g Fe(OH)3 and 3.83 mmol Fe3+ remaining.
*October 28, 2015*

**phsyics**

The block shown in figure below lies on a smooth plane tilted at an angle è = 21.5° to the horizontal. Determine the acceleration of the block as it slides down the plane. Ignore friction.
*October 28, 2015*

**Chemistry**

How do you write the complete ionic equation and net ionic equation for ammonium chloride and copper (II) sulfate in water?
*October 28, 2015*

**Chemistry**

How do you write the complete ionic equation and net ionic equation for ammonium chloride and copper (II) sulfate in water?
*October 27, 2015*

**Chemistry**

I still don't get this problem! Toxic chemicals in drinking water usually are reported and a safety level specified in units of parts per million (ppm) by mass. What is the molar concentration of arsenic in a water sample that has 1ppm arsenic (As)? My teacher's work...
*October 27, 2015*

**Sheridan Road stem **

Write 16/40 in simplest form explain your work???
*October 26, 2015*

**Chemistry**

how many grams of baking soda is needed to neutralize 500ml of hydrochloric acid ?
*October 26, 2015*

**Calculus**

What is the average value of f(x) on [0,4] if the area between the graph of f (x) and the x-axis is equal to 12? I used the average value formula and got 12. But the answer key says 3. My work: M= 1/4 [12x] interval: [0,4] 48/4=12
*October 25, 2015*

**Chemistry -Dr.Bob**

Toxic chemicals in drinking water usually are reported and a safety level specified in units of parts per million (ppm) by mass. What is the molar concentration of arsenic in a water sample that has 1ppm arsenic (As)? DrBob222 1 ppm = 1 mg/L and although that isn't by mass...
*October 25, 2015*

**Chemistry**

Toxic chemicals in drinking water usually are reported and a safety level specified in units of parts per million (ppm) by mass. What is the molar concentration of arsenic in a water sample that has 1ppm arsenic (As)?
*October 23, 2015*

**Algebra**

Tameen keeps quarters, nickels, and dimes in his change jar. He has three more quarters than dimes and five fewer nickels than dimes. If there are 52 coins in the change jar, how many dimes are in the jar?
*October 22, 2015*

**Calculus-Steve**

Find the area of the region between the graphs of f(x)=3x+8 and g(x)=x^2 + 2x+2 over [0,2]. I got 34/3. Calculus - Steve ∫[0,2] (x^2+2x+2) dx = 1/3 x^3 + x^2 + 2x [0,2] = 8/3 + 4 + 4 = 32/3 Why are you taking the antiderivative of x^2 +2x+2 when we are trying to find the...
*October 22, 2015*

**Algebra**

Ticket sale for a music concert was $2,160. Three times as many tickets were sold for the Saturday night concert as were sold for the Sunday afternoon concert. Two times as many tickets were sold for the Friday night concert as were sold for the Sunday afternoon concert. ...
*October 22, 2015*

**Algebra**

The perimeter of MNO is equal to the perimeter of square ABCD. If the lengths of the sides of the triangle are represented by 4x + 4, 5x - 3, and 17, and one side of the square is represented by 3x, find the length of a side of the square.
*October 22, 2015*

**Calculus**

Find the area of the region between the graphs of f(x)=3x+8 and g(x)=x^2 + 2x+2 over [0,2]. I got 34/3.
*October 22, 2015*

**Physics **

A married couple is driving on a dark road at night at the rate of 98.0 m/s until they see a clown 50m in front of them and slam the brakes to slow the car down to 10.0m/s and still manage to hit the clown. How much time would the clown have had to move before being roadkill? ...
*September 20, 2015*

** math**

Triangle ABC is congruent to triangle xyz.write congruence statements comparing the corresponding parts.then determine which transformations map ABC onto xyz
*September 9, 2015*

**Chem**

I did the calculation and I got 4.32 X10^44. Is that correct?
*August 31, 2015*

**Chem**

A pure silver ring contains 2.60X10^22 silver atoms. How many moles of silver atoms it contain?
*August 31, 2015*

**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 clockwise, how many ...
*June 19, 2015*

**Science 207**

Discuss the potential effect of each contaminate oil,vinegar,and detergent on the towns water source and the peopleasure who drink the water
*June 15, 2015*

**Computer Science**

A public transport company provides three types of transports to its passengers to travel from city A to city B of different state. The three types of transports are train, bus and taxi. Each transport has different charges and maximum seats limit. The table below shows the ...
*June 13, 2015*

**algebra**

A soccer field has an area of 312 square yards. Its length is 2 yards longer than twice its width. Find the width of the soccer field.
*June 5, 2015*

**math**

how to cut a 10 ft board into 9 smaller boards
*May 25, 2015*

**Statistics**

The estimate of the population proportion is to be within plus or minus 0.06%, with a 99% level of confidence. The best estimate of the population proportion is 0.22. How large a sample is required? Round answer to the next whole number.
*May 3, 2015*

**Bus 308**

The z score will be comparatively large
*April 26, 2015*

**chemistry **

What is the volume occupied by 0.738g of xenon gas at STP?
*April 23, 2015*

**Math**

The two numbers are 63.36 and 7.04
*April 17, 2015*

**geometry**

A small airplane takes off from point A and continues to climb upward in a straight line, as shown in the diagram. What is the plane’s distance from point A when it reaches point C
*April 7, 2015*

**Math **

a 6,000 seat theater has tickets for sale at $26 and $40 . How many tickets must be sold at each price for a sell out performance to generate a revenue of $190500?
*April 3, 2015*

**Chemistry**

1. Iron oxide and carbon monoxide react according to the following equation . Identify which reactant is limiting and which is excess if 43.5 grams of Fe2O3 reacts with 43.5 grams of CO Fe2O3 + 3CO2 --> 3CO2 + 2Fe 2. Calculate the percent yield of Carbon dioxide if 20.0 ...
*March 19, 2015*

**Chemistry**

What is the empirical formula for a compound that is 1.67g Ce and 4.54g I?
*March 12, 2015*

**Math**

Hello! I need help with this question. I know that I'm using the Law of Sines, but I'm confused on how to solve. I have to also round my answers to the nearest tenth for degrees and to the nearest hundredth for sides. Thanks! Given: A = 60 degrees a = 9 c = 10 Find: b...
*February 24, 2015*

**Math**

@ms sue?
*February 18, 2015*

**Math**

The function f(x) = x^2 -2x + x^1/2 is: A. A polynomial because it is continuous. B. A polynomial because it is of the form axn. C. Not a polynomial because you are subtracting 2x. D. Not a polynomial because you can’t have any fractional exponents. Is the answer D?
*February 18, 2015*

**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 rests on ...
*February 17, 2015*

**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 me how...
*February 17, 2015*

**Math **

if 12 ft of ribbon is cut into pieces that are 2 1/4 ft long,how much ribbon is left over?
*February 17, 2015*

**Algebra 1**

On the second line where you put 3x^2+3x+1x+1 it should really be 3x^2-3x-1x+1 You just lost track of your negative
*February 16, 2015*

**Algebra**

x= -2 y= -6
*February 16, 2015*

**math**

Lee want to cut this piece of canvas into two rectangles that are 3×2 and 3×5. He wants the sum of the area of the two small rectangles to be the same as the area of the large rectangle. 6 feet across and 3 feet. Can he do this. Explain
*January 20, 2015*

**math**

Lee want to cut this piece of canvas into two rectangles that are 3×2 and 3×5. He wants the sum of the area of the two small rectangles to be the same as the area of the large rectangle. 6 feet and 3 feet. Can he do this. Explain
*January 20, 2015*

**Math**

If w is some number between 3 and 10, which of the following could be the average of the numbers 4,5,6,7,9 and w? (A)4.6 (B)5.1 (C)6.3 (D)7.9 (E)8.2
*January 18, 2015*

**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 moon,but the moon is ...
*January 18, 2015*

**math**

A piece of wire 34 cm long is cut into two parts. One part is to twice as long as other. how long is each part? solution pls..
*January 13, 2015*

**math**

May takes 12 hours to type a report. Her friend helps her and together they finish the job in 4 hours. How long would it take her friend had she worked alone? Representation: Equation: Solution: Conclusion:
*January 12, 2015*

**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 machine and you can ping ...
*December 23, 2014*

**english 10th**

How does an open question differ from a closed question?
*December 16, 2014*

**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?
*December 7, 2014*

**Math**

Is it 168?
*November 18, 2014*

**Math**

Mr. Sugar baked a sheet cake in the shape of a rectangular prism with the deminisions of 20in by 12in by 3in high he is going to spread icing all over the cake except for the bottom what is the total surface area?
*November 18, 2014*

**Algebra 1 please help answer**

Its19.2:3
*November 4, 2014*

**soc120**

Which of the following is a claim that utilitarian might use to argue that prayer should not be allowed in school? (Points : 1)
*November 4, 2014*

**chemistry - DrBob?**

Hi! Can you tell me if I chose the right options for my chemistry homework? My answers are at the bottom. 1. Electrostatic interaction is important for which type of bond? A. ionic bond B. triple covalent bond C. single covalent bond D. double covalent bond 2. When an atom ...
*November 2, 2014*

**Chemistry**

Hi! Can you tell me if I chose the right options for my chemistry homework? My answers are at the bottom. 1. Electrostatic interaction is important for which type of bond? A. ionic bond B. triple covalent bond C. single covalent bond D. double covalent bond 2. When an atom ...
*November 2, 2014*

**math**

what is the consecutive positive odd numbers of 34,459,425?
*October 27, 2014*

**Chemistry**

1. The temperature of two substances with the same mass increases by 20 degrees Celsius. Which absorbs the most energy, the substance with the higher or lower specific heat? Explain 2. The human body is approximately 60% water. Explain how this high percentage of water helps ...
*October 21, 2014*

**math**

the number 34,459,425 is the product of several consecutive positive odd numbers. what is the greatest of these numbers?
*October 18, 2014*

**Chemistry**

If 14.23 mL of 0.203 M NaOH is required to neutralize .269 g of a monoprotic unknown acid, what is the molecular weight of the unknown acid?
*October 9, 2014*

**Math Help Please**

ABC Company is about 1614 feet tall. How long would it take an object falling freely from the top to reach the ground? Use a = 16t^2 I would appreciate any help. ^_^
*September 22, 2014*

**Pre-Calculus**

Hi! I'm having trouble with this math question; can someone help? Thanks! :) Given the function f(x)=x^2+9, solve. a.) Find f(-3) b.) Find f(x-2)
*September 16, 2014*

**English**

What is the relationship between literature and place in these narratives "from A Journey Through Texas" and "form of Plymouth plantation"
*September 15, 2014*

**Geometry**

M is the midpoint of LM LM=3x+5 LN=5x+40 Find MN I've tried to work this out several times and am pretty sure I start it off by 3x+5=5(x)+40 but I keep getting a negative answer or a fraction for X and know that is not right. Can someone please help me?
*September 11, 2014*

**Math plz check if correct**

If a term is multiplied by zero, the resulting product will always be ______.
*August 31, 2014*

**Please check my answers ASAP**

after i pass this test ill give u the anwers
*August 29, 2014*

**Algebra**

If you are paid a weekly base salary of $200 plus an hourly wage of $5.00, determine an equation for finding your weekly gross pay (P) for t hours. Specify an amount between 25 and 50 hours worked for 1 week and determine your gross pay for that week.
*August 14, 2014*

**English / Grammar**

Please help me word this sentence correctly: At its zenith, the depression saw nearly 25 percent of all workers and 37 percent of all non-farm workers completely out of work. I'm trying to say that at the peak of the depression, that's how many people were out of work...
*August 10, 2014*

**General Education**

I said that I chose D above.
*July 20, 2014*

**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 statements above are ...
*July 20, 2014*

**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 chances for success...
*July 20, 2014*

**General Education**

Thank you very much!!
*July 20, 2014*

**General Education**

<11{2[3(02)26]}> 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 ...
*July 20, 2014*

**probability and statistics**

Suppose every student in your class got a score of 85% on an exam. What are the mean and standard deviation of those exam scores without doing any calculations? I want to say the mean is 100 and the standard deviation is 1 but I don't know why. If all students scored 85% ...
*June 17, 2014*

**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 snow is .05. How far ...
*June 16, 2014*

**Numer Theory**

1+2+3+...+n=(1+n)+(2+(n-1))+(3+(n-2))+... =(1+n)+(1+n)+(1+n)+... How many copies of n+1 are in there in the second line? with n=6 and n=7
*June 7, 2014*

**SCI 275**

I just did this. Talk about asbestos !!!!!
*May 15, 2014*

**psychology**

Can someone give me an example of correlation and causation.
*April 16, 2014*

**Chemistry**

Thanks for your help. Sorry, I accidentally posted the question again without meaning to.
*April 14, 2014*

**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 = 1.498 - (-0....
*April 14, 2014*

**General Chemistry**

Thanks for your help! I got it now. I messed up with second half reaction, it was supposed to be Cr^2+ + 2e- -> Cr; E = -0.91.
*April 14, 2014*

**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 = 1.498 - (-0....
*April 14, 2014*

**economics**

Do you feel there are any imbalances to our wage structure in our economy?
*April 2, 2014*

**statistics**

a resturant must choose 5 employees from 12 applicants. in how many ways can they do that?
*March 17, 2014*

**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
*March 17, 2014*