# Posts by dan

Total # Posts: 1,181

**Chemistry**

Identify the balanced net ionic equation for the reaction 2Na3PO4(aq) + 3CaCl2(aq)¨ 6NaCl(aq) + Ca3(PO4)2(s)

*April 8, 2010*

**Chemistry**

How many moles of NaBH4 are needed to generate one mole of B2H6 if the reaction gives an 80% yield? 3NaBH4 +4BF3 ¨ 3NaBF4 + 2B2H6

*April 8, 2010*

**Chemsitry**

What is the phase of a compound at 600 mmHg and 32oC if it melts at 35oC when pressure is 760 mmHg? Its triple point occurs at 200 mmHg and 36oC.

*April 8, 2010*

**Chemistry**

How many moles of PCl3 can form from a mixture of 5 mol of P and 6 mol of Cl2 according to the equation 2P + 3Cl2 ¨ 2PCl3

*April 8, 2010*

**Chemistry**

Alum is a hydrated compound containing 45.5% water. How many moles of water are contained in one mole of this hydrate. Data for alum M= 474 g∙mol-1

*April 8, 2010*

**Algebra 2**

it says (3i*ã5)2

*April 1, 2010*

**Algebra 2**

Thanks Reiny How ado I simplify? (3iã5)^

*April 1, 2010*

**Algebra 2**

Can someone help me with this?? Simplify... ã-45 x ã-20 = is it?? ã-45*-20 ã-900 3ã-30

*April 1, 2010*

**ice cream**

Suppose you have a friend named Ed. He and his four friends are having ice cream. There are only three flavors available at the ice cream store they are visiting: chocolate, vanilla, and strawberry. One of Ed’s friends, Stacey, eats chocolate exclusively. How many ...

*March 30, 2010*

**math**

A drawing of diagonals for four different polygons is listed below. What is the number of diagonals for a 100-sided polygon?

*March 30, 2010*

**solving polynomial equations**

thanks and one more thing -4=c-3/6-1-c/8+c/12

*March 27, 2010*

**solving polynomial equations**

please help 3(n+1)=5(n-3) thank you

*March 27, 2010*

**4th grade math**

R^2 + R^2 + 16R + 64 = 144 solve for R.

*March 25, 2010*

**math**

Convert the polar equation r-3cosx = 5sinx in Cartesian equation form.

*March 22, 2010*

**math**

How do you convert polar coordinates to Cartesian coordinates? And vise versa.

*March 19, 2010*

**trig**

How do you convert polar coordinates to Cartesian coordinates? And vise versa.

*March 19, 2010*

**math**

Two forces of 7 lb. and 14 lb. act on a body at right angles to each other. Find their resultant. Find the angle their resultant force makes with the force of 14 lb.

*March 17, 2010*

**math**

According to Sal's map he is is 6 units away from the grocery. The grocery store is 5 units away from the coffee shop. The coffee shop is 1 unit away from Sal's house. How is this possible?

*March 16, 2010*

**Chemistry**

Which test for iron(II) ions is conclusive?

*March 16, 2010*

**Duval**

Explain the importance of understanding inventory valuation methods in dertermining the quality of the profit

*March 9, 2010*

**Physics**

7.8hz

*February 26, 2010*

**English**

Midsummer Night's Dream: The fourth act opens with Bottom at center stage. What is your opinion of Bottom's character? How might he be the antithesis, or opposite of Theseus's character?

*February 15, 2010*

**math**

Examine three elementary schol textbook and report on how the introduction of the topic of GCD and LCM differ in the diffrent textbooks?

*February 9, 2010*

**Chemistry**

An element has bcc packing with a body-centered cubic unit cell. Its density is 19300 kg/m3 and the unit cell volume is 3.17 x 10-26 L. Calculate the molar mass (g/mol) of the element to three significant figures. The element rubidium has bcc packing with a body-centered cubic...

*February 8, 2010*

**Finance**

I need to identify the ROI and NPV of the wireless order-tracking system. Here is the information it gives me: - The aquisition cost is $35,000 paid at the time of installation. - It reduces the wait staff by one person: Figure $10 per hour, or 2020 hours per year + 18% ...

*February 5, 2010*

**US History**

I need to pick a term paper topic involving American History. I want to do something about a controversy during a war time, but I don't know what to pick. Maybe something during the Vietnam War or the Gulf War? Where could I find thesis ideas or do you have any suggestions?

*February 3, 2010*

**Geometry.**

A spherical water tank has a diameter of 10 feet. How much water does it hold when half full (use 3.14 for , and round to the nearest hundredth)?

*January 24, 2010*

**Trigonometry**

If the sine of an angle is 3/5 and the angle is not in quadrant 1, what are the remaining five trigonometric values for that angle?

*January 24, 2010*

**Math**

How would you graph the inequality x > -5

*January 24, 2010*

**Math**

How would you graph the inequality x > -5

*January 24, 2010*

**spell**

Whirlwind: breeze:: downpour:

*January 21, 2010*

**science**

I AM IN YEAR THREE I NEED SOME HELP IN MATERIALS (SCIENCE)

*January 4, 2010*

**geomitry**

a sperical water tank is being filled with the diamiter of 10 feet how much water does it hold half full use 3.14

*December 15, 2009*

**critical thinking**

how will thinking critically influence the way I read? how will thinking critically influence the way I write? how will thinking critically influence the way I process information?

*December 9, 2009*

**sci275**

how can the government be involved in conservation efforts?

*December 8, 2009*

**chemistry**

An engine goes through the following cycle with 2.60 moles sample of a diatomic gas. I. an isothermas expansion from point a to point b. II. a constant pressure compression from point b to point c. III. an adiabatic compression from point c to point a. We are given point a has...

*December 7, 2009*

**chemistry**

An insulated beaker with negligible mass contains liquid water with a mass of 0.255{kg} and a temperature of 76.0{C} How much ice at a temperature of -19.9 C must be dropped into the water so that the final temperature of the system will be 32.2? Take the specific heat of ...

*December 7, 2009*

**HCA220**

I answered several question for an assignment and I need help to understand how I got it wrong. The assignment dwelt medical terms. The following three were marked wrong. Please help! Use the word bank below to build the medical word that corresponds to each definition in ...

*November 30, 2009*

**environmental science**

can you name one terrestrial resource issue?

*November 29, 2009*

**environmental science**

why is sewage a problem and how have human activities contributed to this problem?

*November 20, 2009*

**Chemistry problem**

What is the expected freezing point of a 3.50 m aqueous solution of BaCl2 (Kfp=1.86C/m)? What is the boiling point (Kbp=0.512C/m? & which is affected to the greater extent, the boiling point or the freezing point?

*November 12, 2009*

**Simple Chem Help**

fill in the blank. The freezing point of a solution is_____ and the boiling point is ___________ than that of a pure solvent. lower...higher?

*November 12, 2009*

**calculus**

Water is leaking out of an inverted conical tank at a rate of 60000 cubic centimeters per min at the same time that water is being pumped into the tank at a constant rate. The tank has height 90 meters and the diameter at the top is 40 meters. If the water level is rising at ...

*November 10, 2009*

**Chemistry**

I thought I put it as soluble, because I broke it up to 2Ti+(aq)and SO42–(aq. Correct me if I'm wrong. Is the rest okay?

*November 7, 2009*

**Chemistry**

Could some please tell me if I did these problems correctly? (I know that I did not Cancel common aqueous ions yet) Question: Write the net ionic equation for the following 1)Mixing solution of barium acetate and sodium phosphate 2)Mixing solution of thallium sulphate and ...

*November 7, 2009*

**Physics**

hahaa.. funny. I had to show the calculations for each step. So are you suggesting that I just state that this proves the Conservation of Energy?

*November 6, 2009*

**Physics**

This is a four part question, I need help with the fourth part. 1. I found the Gravitational Potential Energy of a gymnast at her maximum height above a trampoline to be 400J. 2. I found the Kinetic Energy of her just before she makes contact with the trampoline to also be ...

*November 6, 2009*

**5th grade**

4/5-7/8/10-7/10+1/2=6/10+1/5=8/10

*November 6, 2009*

**college physics**

A 190 g air-track glider is attached to a spring. The glider is pushed in 9.8 cm and released. A student with a stopwatch finds that 14 oscillations take 18.5 sec. What is the spring constant?

*October 30, 2009*

**algebra**

7.3xgreater than or less than -87.6

*October 27, 2009*

**pre-algebra**

mr conner's students made kites in science class. he brought a 500-yd bolt of twine to tie to the kites. if he wants to give each student a piece of twine 331/3 yards long. what is the maximum number of pieces of twine mr. conner will be able to make from the bolt of twine?

*October 27, 2009*

**pre algebra**

w+9/14 greather than or equal to 5/14

*October 27, 2009*

**pre-algebra**

-1.04

*October 27, 2009*

**pre-algebra**

x/-2.5<-1.54 solving ineualities with rational numbers'---how do i do this?

*October 27, 2009*

**science 8th**

give an example of a chemical formula.

*October 27, 2009*

**math**

5^6-2=

*October 25, 2009*

**college**

A proton is traveling to the right at 2.5×10^7m/s . It has a head-on perfectly elastic collision with a carbon atom. The mass of the carbon atom is 12 times the mass of the proton. What are the speeds of each after the collision?

*October 18, 2009*

**physics**

Ball 1, with a mass of 100g and traveling at 12 m/s , collides head on with ball 2, which has a mass of 340g and is initially at rest. What are the final velocities of each ball if the collision is perfectly elastic? What are the final velocities of each ball if the collision ...

*October 18, 2009*

**math**

how do i simplifu 2r^2 +r +r^2 and 3(r+s) - 2r

*October 17, 2009*

**English**

Selfish in a sense that most of us fall upon reacting against the injustice of the world upon reacting against the injustice of the world. should there be an "s" at the end of fall?

*October 15, 2009*

**lit**

how do you convert mg/ml to mg/100mol

*October 14, 2009*

**physics**

A 1100 kg sports car accelerates from 0m/s to 33m/s in 13s What is the average power of the engine?

*October 12, 2009*

**physics**

An elevator weighing 2400 N ascends at a constant speed of 5.0 m/s. How much power must the motor supply to do this?

*October 12, 2009*

**physics**

What minimum speed does a 150g puck need to make it to the top of a 3.6m -long, 23 degree frictionless ramp?

*October 12, 2009*

**physics**

How much work must you do to push a 13 block of steel across a steel table at a steady speed of 1.3 for 3.7 ? what is the Wnet and P?

*October 12, 2009*

**physics**

A 710 kg car drives at a constant speed of 23m/s . It is subject to a drag force of 500 N. What power is required from the car's engine to drive the car (a) on level ground? (b) up a hill with a slope of 2.0?

*October 12, 2009*

**physics**

With what minimum speed must you toss a 160 ball straight up to hit the 15 -high roof of the gymnasium if you release the ball 1.7 above the ground? Solve this problem using energy.

*October 12, 2009*

**11th grade**

An improper fraction is usually something over something. The numerator in a improper fraction is usually larger than the denominator. =10*12+5/12 =125/12 =31/3

*October 10, 2009*

**Alg**

I have to simplify this: (y^(1/4)*Z^4)^(-4/5) My answer: (2z)^(1/2)/4z^4 Correct? Simplify (3-2SQRT2)(SQRT6-5) I have no idea how to foil this one.

*October 9, 2009*

**Algebra**

I have to simplify this: (x^(1/2) * z^(-4/5)^4 My work: x^2/z^(16/5) Correct? Simplify (3+5SQRT2)(4+SQRT10) I have no idea how to foil this one.

*October 8, 2009*

**Physics**

My Prof. used the equation ---- (G*Me)/((Re+h)^2)=g' He said to solve for h which is what I did but it didn't work. Suggestions?

*October 6, 2009*

**Physics**

A sensitive gravimeter at a mountain observatory finds that the free-fall acceleration is 7.0×10−3 less than that at sea level. What is the observatory's altitude?

*October 6, 2009*

**Physics**

A 300 ball swings in a vertical circle at the end of a 1.2-m-long string. When the ball is at the bottom of the circle, the tension in the string is 13 . What is the speed of the ball at that point?

*October 6, 2009*

**biology**

what can be a represent as a necleus in a room. and WHY

*October 5, 2009*

**SraJMcJin**

Hello, I was wondering if you could read my essay and tell me what you think i could do to improve on it. The problem is, I do not want to put it on the internet, so is there a way I can email you my essay?

*October 5, 2009*

**algebra**

(4c+2)+(5c) = 92 9c + 2 = 92 9c = 90 c = 10 So there are 10 chairs in each row Alexi set up a total of 42 chairs including the extra 2. Martin set up a total of 50 chairs. 42-(2*4) + 50-(2*5) = ?? 92 - 18 = ???

*October 4, 2009*

**English+Essay**

Also whats a good way to end your paragraphs? do i just restate what i wrote?

*October 4, 2009*

**English+Essay**

If I start the introductory paragraph to: As a candidate for National Honor Society membership, I believe that I exemplify the high standards expected of its members. Would I need to add on more to it to make it a little bit longer? I was thinking about adding this to it: I ...

*October 4, 2009*

**English+Essay**

I have to write an essay, but I have no idea how to start it. It says that my essay has to be MLA formatted, and only 3/4 to 1 page long. 2 page is the longest it can be and must be double placed. Using MLA format, there's is no way for me a write a proper essay with that ...

*October 4, 2009*

**math**

There are two machines that produce aluminum cans. The newer machine can produce 7200 cans in 200 minutes. It takes the older machine 300 minutes to produce that many cans. If the two machines work together, how long will it take them to produce 7200 cans? i did 200x+300x = ...

*October 1, 2009*

**math**

The length of a rectangle is four times its width. If the perimeter of the rectangle is 50cm. find its area. how do i set this up?

*October 1, 2009*

**math**

Justin's gas tank is 1/4 full. After he buys 9 gallons of gas, it is 5/8 full. How many gallons can Justin's tank hold? How would i set that up?

*October 1, 2009*

**math**

1. Jina purchased a prepaid phone card for $15. Long distance calls cost 11 cents a minute using this card. Jina used her card only once to make a long distance call. If the remaining credit on her card is $11.04 , how many minutes did her call last? I got 3.96 minutes is that...

*October 1, 2009*

**social studies**

a big one. as one might expect whensomeone moves into you bnackyard with tyechnology youve never seen

*September 19, 2009*

**AP English**

well, first, God is someone to be afraid of, although loves and thanked too, for pouring his wrath for sinners on His son who died willingly, saving and covereing the sins of anyone who beleives in Him... (this is because Lincoln was a christian..) other than that, its really ...

*September 19, 2009*

**math**

ur answer is odd numbers welcome for noing da answer(:!!!!! WELCOME EVERYONE!!!!!

*September 17, 2009*

**math**

yay :p thanks

*September 5, 2009*

**math**

(4)^2(8) - 12 (16)(8) - 12 128 - 12 = 116 ??

*September 5, 2009*

**math**

can you check if answer is right? a^2b -c when a=4 b=8 and c=12

*September 5, 2009*

**Math**

typo # 4 answer = -5,9

*September 1, 2009*

**Math**

Hello I did my math homework, but I need someone to check if I did it right or not. 1. A = z>=4 B = z<7 Write A or B and A and B using interval notation Answer: A or B = (-infinity, infinity) A and B = [4,7) 2. Write the algebraic expression for the following: 8 is less ...

*September 1, 2009*

**physics**

I can't fully understand Fermat's principle of least time (the modern version)

*July 27, 2009*

**math**

Identify the conic section whose equation is given: x2 + 10x + y2 + 12y = 60

*July 25, 2009*

**math**

what's a point of inflection

*July 25, 2009*

**chemistry**

I only need help with step 3 We are trying to figure out the charge on Nickel. So we performed titrations. First, 0.6215 g sample of nickle metal was dissovled in 100.0ml of Fe^3+.(acid based) Then, 15.00 ml sample of this solution was taken and titrated. If it took 26.48ml of...

*June 27, 2009*

**chemistry**

Heres the simplified version: I need to convert Ni to moles: I have a 0.6215 g sample of Ni that was dissolved in 100.00ml of Fe 3+. Then, 15.00 ml of the sample was taken and titrated. It took 26.48 ml of .0200M Cr2072- to titrate the solution. ] I did the following to find ...

*June 27, 2009*

**chemistry**

hi, Im not sure how to explain this well but here goes. Im doing a oxidization/reduction reaction to determine the charge of an element. charge is n formula n=a/b Problem: 0.6215 g sample of nickle metal was dissovled in 100.0ml of fe 3+ Note for the formulas: I put all the ...

*June 27, 2009*

**chemistry**

nope not yet

*June 21, 2009*

**chemistry**

what are some source errors in my experiment? determine absolute zero. We attached a capillary to a ruler with a thermometer. placed it in water and heated. I recorded and my partner did the readings. source errors: -partner didn't stir the water before he took the ...

*June 21, 2009*

**chemistry**

here this might help 4 C3H5(NO3)3(l) → 12 CO2(g) + 10 H2O(g) + 6 N2(g) + O2(g) I must have copied it wrong into the browser. sorry...

*June 21, 2009*