Friday

April 18, 2014

April 18, 2014

Number of results: 39,390

**Chemistry**

Since KOH is a strong base, it totally dissociates, and thus the concentration of hydroxide ions in solution equals to the concentration of the KOH. 0.70M KOH note that: [H+][OH-]= 1.0 x 10^-14 so, [H+]= 1.0x10^-14 / [0.70M] = ______[H+] since pH = -log[H+] plug in the [H+] ...
*Tuesday, February 10, 2009 at 10:05pm by ~christina~*

**Chemistry**

A beaker with 150 mL of an acetic acid buffer with a pH of 5.00 is sitting on a benchtop. The total molarity of acid and conjugate base in this buffer is 0.100 M. A student adds 5.60 mL of a 0.280 M HCl solution to the beaker. How much will the pH change? The pKa of acetic ...
*Thursday, July 9, 2009 at 2:01am by Saira*

**chemistry help!!**

A beaker with 195 mL of an acetic acid buffer with a pH of 5.00 is sitting on a benchtop. The total molarity of acid and conjugate base in this buffer is 0.100 M. A student adds 8.20 mL of a 0.260 it M HCl solution to the beaker. How much will the pH change? The pKa of acetic ...
*Monday, July 13, 2009 at 1:10pm by DrFunk*

**Chemistry**

A beaker with 150 mL of an acetic acid buffer with a pH of 5.00 is sitting on a benchtop. The total molarity of acid and conjugate base in this buffer is 0.100 M. A student adds 7.90 mL of a 0.480 M HCl solution to the beaker. How much will the pH change? The pKa of acetic ...
*Tuesday, October 6, 2009 at 8:06pm by Anonymous*

**Child Psychology**

I am a little confused by the way your question is phrased. If both T and t are for "tallness," then all of the children will be tall. If T is for normal height and t is for tallness, then only the tt genotype would be tall. If t is for normal height and T is for tallness, 3/4...
*Saturday, July 4, 2009 at 5:50pm by PsyDAG*

**Physics**

A horizontal force of 100 N pushes a 12kg block up a frictionless incline that makes an angle 25degrees with the horizontal. What is the normal force that the incline exerts on the block and what is the acceleration of the block? I found part (a) which is the normal force. It ...
*Monday, September 20, 2010 at 7:39pm by Anonymous*

**Math help**

Can someone give me a heads up on how to even start this problem.. Consider the following. (Give your answers correct to two decimal places.) (a) Find the standard score (z) such that the area above the mean and below z under the normal curve is 0.3989. (b) Find the standard ...
*Friday, June 14, 2013 at 4:54pm by Tom 6*

**Chemistry**

The details are missing but if you titrated with a curve, then you know where the equivalence point is. Read mL acid at that point, take 1/2 of that volume in mL, then read from the graph the pH at the half-way point. The pH = pKb at the half-way point.
*Thursday, March 28, 2013 at 8:56pm by DrBob222*

**chemistry**

Some properties of aluminum are summarized in the following list. normal melting point 658°C heat of fusion 0.395 kJ/g normal boiling point 2467°C heat of vaporization 10.52 kJ/g specific heat of the solid 0.902 J/g°C (a) Calculate the quantity of energy required to heat 1.75 ...
*Saturday, May 1, 2010 at 5:54pm by Jake*

**Chemistry**

Some properties of aluminum are summarized in the following list. normal melting point 658°C heat of fusion 0.395 kJ/g normal boiling point 2467°C heat of vaporization 10.52 kJ/g specific heat of the solid 0.902 J/g°C (a) Calculate the quantity of energy required to heat 1.75 ...
*Saturday, May 1, 2010 at 6:46pm by Charles*

**chemistry**

A solution of sodium cyanide nacn has a ph of 12.10. How many grams of nacn are in 425ml of solution with the same ph? I do not understand how to calculate this question. Who helps me to solve it for me. Thank you. The right answer 209gm. A 0.446g sample of an unknown ...
*Saturday, August 11, 2012 at 10:38pm by Fai*

**Statistics help**

Consider the following. (Give your answers correct to two decimal places.) (a) Find the standard score (z) such that the area above the mean and below z under the normal curve is 0.3989. (b) Find the standard score (z) such that the area above the mean and below z under the ...
*Friday, June 14, 2013 at 6:53pm by DeeDee6*

**SCI 275**

You might be falling into the trap (I think) of using information in the MSD on its own? You will need to use the MSD info in the context of the material being used. So start from the MSD and list the hazards. Think the process cycle through, how is the material being: stored ...
*Sunday, December 19, 2010 at 8:15pm by Dr Russ*

**Math**

Let X be the distance of the dog with the 35 degree elevation angle from the tree. The other dog is 180-X away (in feet). Let H be the height of the tree. You have these two equations in two unknowns: H/X = tan 35 = 0.7002075 H/(180-X) = tan 23 = 0.4244748 Solve for X first by...
*Wednesday, July 30, 2008 at 6:24am by drwls*

**math**

c= 600 1 360.75 1 1 .35.75 = 450-360 .75-.35=90 .4=225
*Sunday, January 25, 2009 at 10:36am by christeria*

**chemistry**

What is the pH of a solution prepared by dissolving 8.40 g of aniline hydrochloride C6H5NH3Cl in 750 mL of 0.210 M aniline,C6H5NH2? i kno to use the ph = pka + log (base/acid). getting pka isnt the issue, but what do i put into the log (base/acid)? (0.210/????) thanks
*Wednesday, April 7, 2010 at 6:25am by anonymous*

**chemistry**

What is the pH of a solution prepared by dissolving 8.40 g of aniline hydrochloride C6H5NH3Cl in 750 mL of 0.210 M aniline,C6H5NH2? i kno to use the ph = pka + log (base/acid). getting pka isnt the issue, but what do i put into the log (base/acid)? (0.210/????)
*Thursday, April 8, 2010 at 12:34am by anonymous*

**Chemistry**

Let's call oxalic acid H2Ox, then H2Ox ==> H^+ + HOx^- K1 = (H^+)(HOx^-)/(H2Ox) = 6.5 x 10^-2 then (H^+) = y which you have (I don't want to use x because we have x in the oxalate). and (HOx^-) = y which you have. and (H2Ox) = 0.0652-y You can solve this quadratic for y. ...
*Monday, March 29, 2010 at 5:28pm by DrBob222*

**MATH**

(1/2) b h = 17.5 (1/2) b (b+2) = 17.5 b^2 + 2 b = 35 b^2 + 2 b - 35 = 0 (b - 5)(b+7) = 0 b = 5 h = 7
*Sunday, July 13, 2008 at 8:04pm by Damon*

**Math**

7 / 3 a + 2 / 5 = ( 7 * 5 + 2 * 3 a ) / ( 5 * 3 a ) = ( 35 + 6 a ) / 15 a = ( 6 a + 35 ) / 15 a
*Sunday, June 9, 2013 at 5:44pm by Bosnian*

**physics**

Vp = 243m/s * (1/1000)km/m * 3600s/h = 875km/h. = Velocity of plane. Vw = 49.9m/s * (1/1000)km/m * 3600s/h = 180km/h = Velocity of the wind. d1 = d2, (875-180)t = (875+180)(5.57-t), 695t = 1055(5.57-t), 695t = 5876.35 - 1055t, 695t + 1055t = 5876.35, 1750t = 5876.35, t = 3.36h...
*Thursday, October 6, 2011 at 6:48pm by Henry*

**Science - biology - university**

A couple where both the man and woman are albino decided to have children. Remember that albinism is inherited as a rare autosomal recessive trait. To their surprise their first child had normal skin pigmentation. They eventually have two more children and they also have ...
*Monday, September 27, 2010 at 1:43pm by Axel*

**AP Physics PLEASE HELP DUE TOMORROW**

A young male adult takes in about 4.0 10-4 m3 of fresh air during a normal breath. Fresh air contains approximately 21% oxygen. Assuming that the pressure in the lungs is 1.0 105 Pa and air is an ideal gas at a temperature of 310 K, find the number of oxygen molecules in a ...
*Tuesday, December 21, 2010 at 10:20pm by Sarah*

**Math**

I would take the 80% with a standard deviation (σ) of 3%. This way, 68% of the time, I would get between 77% and 83%, and 95% of the time I get between 74% and 86%. If you are a risk taker and take σ=15%, then there is a 9.12% that you'll get below 60%. Check my ...
*Friday, December 3, 2010 at 8:19am by MathMate*

**Pre-Cal(Please help)**

solve for r There is a right triangle with the hypotenuse as r , the angle as 45 degrees and opposite side as 20. I am having a hard time finding this out. I had tan 45 = 1.61 20(1.61) = 32.4 but this is wrong.
*Tuesday, March 23, 2010 at 1:05pm by Hannah*

**physics**

2m*sin(45)= length of fall (LOF) this needs to be plugged into equation henry posted. The suitcase does not fall 2m unimpeded. It slides down the ramp at 45 degrees. Thus trig is needed to solve.
*Wednesday, January 19, 2011 at 12:43am by Adam*

**Science**

The gravitational force of any object near Earth is _____? A unknown B friction C Newton's First Law D 9,8m/s2 When you walk across a bridge, the _____ force of the bridge keeps it from breaking. A gravitational B normal C strong D weak A (n) _______________ helps reduce ...
*Tuesday, November 9, 2010 at 6:55pm by Jacob*

**Stats**

Z = (score-mean)/SEm SEm = SD/√n Assuming a normal distribution, find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability (.05) and its Z score. Insert Z score and other data into the top ...
*Friday, December 13, 2013 at 8:31am by PsyDAG*

**Math**

To carry that a bit further odds = probability of what you want / probability of what you do not want you want odds against A so probability of what you want is 35/36 and the probability of what you do not want is A or 1/36 so odds against A are (35/36) / (1/36) = 35 to 1 ...
*Sunday, March 21, 2010 at 11:11am by Damon*

**Chemistry**

I still don't get it. pH = pKa + log(B/A) 5.00 = 4.76 + log(B/A) B/A = 1.7378 A + B = 0.100 Two equation in two unknowns. A = your number B = your number. You started with 100 mL; therefore, you started with 3.653 mmoles HAc (which may be the difference) and 6.347 mmoles Ac^- ...
*Friday, March 18, 2011 at 8:57pm by DrBob222*

**chemistry**

First you recognize that HCl is a strong acid and ionizes completely; therefore, HCl + H2O ==> H3O^+ + Cl^- So if you start with 0.00010 M HCl,knowing it is ionized completely, the H3O^+ must be 0.00010. pH = -log(H^+) = -log(0.00010) = -(-4.0) = 4.0 and pH = 4.0
*Monday, March 23, 2009 at 7:23pm by DrBob222*

**Chemistry**

The pH will be determined by the hydrolysis of the salt, NaX. ...........X^- + HOH ==> HX + OH^- initial..0.10.............0....0 change....-x..............x.....x equil....0.10-x...........x.....x Kb for the salt = (Kw/Ka) = (x)(x)/(0.10-x) Kw = 1E-14 Ka is Ka for HX, ...
*Friday, October 21, 2011 at 8:05pm by DrBob222*

**Chemistry**

In its simplest form, a buffered solution resists a change in pH. An unbuffered solution does not. For example, a buffered solution of acetic acid and sodium acetate will change pH only slightly when 1 ml of strong acid (HCl for example) is added. But 1 mL HCl added to an ...
*Sunday, March 23, 2008 at 9:16pm by DrBob222*

**social studies**

You'll find several physical and human features of Tokyo in the first paragraph of this site. http://en.wikipedia.org/wiki/Tokyo You could also include its latitude and longitude as a physical feature. 35 degrees, 50 minutes N 139 degrees, 45 minutes E
*Tuesday, August 9, 2011 at 6:01pm by Ms. Sue*

**Chemistry**

see same question how many grams nitric acid HNO3 must be dissolved in 350 ml water to make a solution with pH of 4.5"? or "how many ml of a 4.2M nitric acid solution are required to make 500 ml of solution with pH of 2.9
*Sunday, May 12, 2013 at 11:29am by kriti*

**anatomy**

if you wanted to flex your arm, and both your biceps and triceps contracted simultaneously, what would happen? and where is most of the muscle weight found in humans?
*Sunday, October 28, 2007 at 8:32pm by sara*

**anatomy**

if you wanted to flex your arm, and both your biceps and triceps contracted simultaneously, what would happen? and where is most of the muscle weight found in humans?
*Sunday, October 28, 2007 at 10:11pm by sara*

**Science**

I was wondering if anybody knew of a web-site that may help be find information on how humans can harbor many microorganisms on and inside their bodies without experiencing symptoms of infection thanks for you help
*Sunday, April 6, 2008 at 9:42pm by Anonymous*

**english 12**

thanks, humans are causing killing all the animals, polluting the plants, pollution, ozone, basically messing up the biodiversity of the species...
*Tuesday, October 21, 2008 at 6:46pm by ben*

**biology**

To the extent that these organisms are like us, we can find information that is likely to apply to humans (e.g., medical treatments). I hope this helps a little more.
*Wednesday, January 20, 2010 at 12:04am by PsyDAG*

**Biology**

Living organisms include everything from microbes to farm crops to rain forest plants to earthworms to zebras to chimpanzees to humans.
*Monday, March 15, 2010 at 8:55pm by Ms. Sue*

**English**

Hi Iam doing an article on why I think humans should not eat meat from the perspective of a parent with a child. I need three solid arguments for this; please help.
*Monday, November 15, 2010 at 6:28pm by Serena*

**Animal Skeletal and Muscular Systems**

1. b 2. c 3. d 4. a 5. b 6. d 7. a 8. c 9. d 10. c (? Thats how many for humans) 11. d 12. a 13. d 14. c 15. d 16. c 17. c 18. d 19. a 20. b
*Wednesday, September 21, 2011 at 11:36pm by Corey*

**Science**

humans,other mammals,birds can maintain a constant body temperature. why is this a useful adaptation? how does this explain the spread of these animals around earth?
*Wednesday, October 17, 2012 at 10:43pm by esha*

**english**

animals posses sensory powers that humans lack. Homing pigeons fly with great speed and accuracy when with messages to faraway places
*Sunday, September 29, 2013 at 7:46pm by Anonymous*

**chem**

How did you do part 1. You had moles NaOH and moles HCl (HCl in excess), yo subtracted moles HCl-moles NaOH to arrive at moles HCl in excess. I think that is 0.69 millimoles and that divided by the volume (8 mL + 1.1 mL = 9.1 mL) = 0.0758 M and pH = 1.12. So for part 2, you ...
*Thursday, April 29, 2010 at 12:13am by DrBob222*

**Chemistry**

The average pH of precipitation in rural areas is 5.70. Assuming that the pH
is controlled by the carbonate system, i.e., no anthropogenic acid gases are present
in the atmosphere, calculate the amount of calcium carbonate (mg) dissolved per liter
of ...
*Tuesday, April 13, 2010 at 1:06pm by Anonymous*

**physiology**

when the pH of the extracellular fluid DECLINES the a) pH of the urine increases b) kidneys reabsorb less water c) kidneys excrete more sodium ions d) kidneys secrete more potassium ions e) kidneys excrete more bicarbonate ions study guide question thank you
*Monday, December 11, 2006 at 4:17am by pbear*

**Math**

the prob of selecting a tragedy = 18/53 prob of not section a tragedy = 35/53 odds against selecting a tragedy = (35/53 / (18/53+ = 35 : 18
*Sunday, March 24, 2013 at 1:51pm by Reiny*

**Algebra**

Solve the polynomial x^2+35x+27 Is this polynomial equal to something? Assuming it is equal to zero x= (-35 +- sqrt (35^2 -4*27) )/2
*Tuesday, May 8, 2007 at 4:39pm by A*

**math**

20/2.80=35/x 20x=35*2.80 20x=98 divided by 20 on both sides x=4.90?
*Tuesday, May 3, 2011 at 6:51pm by natalie*

**Math**

35 = books other than fantasy 50 = number of books that are fantasy So, the answer is 35:50, and it equals 85.
*Friday, February 14, 2014 at 5:23pm by Brady*

**statistic****help*******

A) 0.53/1.00=0.53 B) 0.25/1.00=0.25 C) 0.47+35=.82 D) 0.04 +0.35=.39 IS THIS CORRECT
*Wednesday, March 19, 2014 at 8:20am by Anonymous*

**Chemistry**

d1 = m1/v2 = 2.70 g/cc m1 = 1.35*m2 so m2 = m1/1.35 V1 = 0.792*v2 so v2 = v1/0.792 d2 = m2/v2 d2 = (m1/1.35)/( v1/0.792) d2 = m1/1.35 x 0.792/v1 but m1/v1 = 2.70 then d2 = 2.70 x (0.792/1.35) = ? Check this.
*Sunday, September 1, 2013 at 11:19am by DrBob222*

**Math: i do not understand**

For a step by step explanation, see http://stattrek.com/Tables/Normal.aspx
*Friday, May 7, 2010 at 12:10am by drwls*

**chemistry- electrochem**

just one thing on this dr bob, i thought that it was Ecell= E*cathode-E*anode. Why do you have a + sign between the 2. E1+E2? your way i get 0.35+(-0.13)=0.22, but my way i get 0.35-(-0.13)=0.48? which one?
*Wednesday, September 15, 2010 at 4:06am by lucylu*

**MATH- Algebra 2**

Solve each quadratic in form equation. 1. 4y^4+9=13y^2 2. x-3x^1/2+2=0 3. (x-5)^2+2(x-5)-35=0 4. (x-2)^2-3x-2)+2=0 5. 2(x^2-5)^2-13(x^2-5)+20=0 6. 2x^2/3+5x^1/3-6=0 7. 6x^2/3-5x^1/3-6=0 8. x^-2+4x^-1=12 9. x^4-8x^2+7=0 10. x^4-2x^2-35=0 can someone please help?
*Sunday, February 17, 2013 at 4:56pm by Blair*

**English**

Hello. Thank you for answering my previous question. I would be very grateful for some more help. 1)In one of the sources I came across the phrase "the nobility was coopted from the military". Does "co-opted" here mean "drawn, incorporated from"? (the source is a transltion ...
*Sunday, December 8, 2013 at 1:18pm by Nalmi*

**Chemistry**

With the Henderson-Hasselbalch equation. pH = pKa + log [(base)/(acid)] You have pH and you can look up pKa. Solve for (base)/(acid) ratio. The second equation you want is base + acid = 0.5 M Solve the two equations simultaneously.
*Saturday, October 30, 2010 at 7:29pm by DrBob222*

**Chemistry**

1. As the strength of a weak acid increases, the proportion of ions to molescules increases or decreases? ... I think that it will increase. Is this right? 2. As the as the concentration of a weak acid increases, the pH... decreases? Is decreases correct? 3. at the same ...
*Friday, May 4, 2012 at 9:11am by April*

**Physics**

If you increase the angle of inclination, does the kinetic friction an object experiences while moving down this inclination increase? I was thinking since Kinetic friction= coffient of friction * Normal force that it does not change, since the coefficient and normal force ...
*Wednesday, October 21, 2009 at 10:48pm by sam*

**statsitsc**

http://stattrek.com/lesson2/normal.aspx
*Saturday, August 20, 2011 at 7:47pm by TutorCat*

**Chemistry**

pH = 11.65. Convert to pOH from pH + pOH = pKw = 14, then convert (OH^-) in moles/L = approximately 4E-3M but you should do it more accurately. You want only 799.2 mL; therefore, M x L = moles = 4E-3 x 0.7992 = ?moles Then grams = moles/molar mass. Solve for grams.
*Wednesday, November 23, 2011 at 7:10pm by DrBob222*

**physics**

A sports car of mass 950 kg (including the driver) crosses the rounded top of a hill (r = 88 m) at 27 m/s. Determine the normal force exerted by the road on the car. Determine the normal force exerted by the car on the 72-{\rm kg} driver.
*Monday, October 11, 2010 at 2:24pm by angela*

**URGENT!! 7th Grade Math Help Please!!**

first thing about percentage problems think either decimals or factions. Decimals if your teacher is nice and lets you use a calculator. .15*329=$49.35 will be taken off the original price $329.00-$49.35=$279.65 new discounted price Now for the fractional version if you like ...
*Monday, December 3, 2012 at 12:19am by Shawn*

**math**

To find the perimeter, you just have add the length+width+length+width. In this case, the answer will be: 1 250m 80 80 45 + 45 ________ 250
*Tuesday, December 18, 2012 at 12:46pm by Katrina*

**Physics**

Let the image distance be Di 1/45 + 1/Di = 1/15 1/Di = 2/45 Di = 22.5 cm You do not need to know that the lens is double convex. All you need is the focal length.
*Thursday, May 9, 2013 at 10:46pm by drwls*

**Stats**

How many ways to choose 2 boys and 3 girls from a class of 10 boys and 15 girls? Would you do: 10C2=45 15C3=455 (45)(455)=20,475?
*Saturday, February 8, 2014 at 3:26pm by Ashley*

**chemistry**

The indicator methyl red has a pKhln=4.95 . It changes from red to yellow over the pH range from 4.4 to 6.2. If the indicator is placed in a buffer solution of Ph = 4.56, what percent of the indicator will be present in the acid form,Hln- , AND what percent will be present in ...
*Thursday, April 14, 2011 at 8:41am by Carmel R.*

**Chemistry**

The pH is determined by the hydrolysis of the salt. ........SO3^2- + HOH ==> HSO3^- + OH^- initial..1.0.............0.........0 change...-x..............x.........x equil...1-x..............x.........x Kb for SO3^2- = (Kw/k2 for H2SO3) = (HSO3^-)(OH^-)/(SO3^2-) Substitute ...
*Tuesday, April 3, 2012 at 3:58pm by DrBob222*

**MATH**

Z score is the raw score in terms of standard deviations from the mean. The Z score cuts off the same proportion for any normal distribution. Z = (score-mean)/SD Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the...
*Monday, September 9, 2013 at 5:29pm by PsyDAG*

**math**

-5(4w + 12 ) = 15 use distributive property to solve -20w-60=15 -20w=-45 -20w/-20w=-45/-20 w=2.25 or 9/4 thanxz
*Monday, February 26, 2007 at 4:54pm by jose*

**physics**

How much time does it take to fall 8 feet? h=1/2 g t^2 8=1/2 32 t^2 t^2=1/2 t= .707 sec distance= Vi*.707=45 vi= 45*sqrt2 ft/sec
*Tuesday, February 9, 2010 at 8:47pm by bobpursley*

**MATH 11 help PLease!**

To get 5, DRAW A Picture 9 foot fence at 0, 11.25 , 22.5 , 33.75 , 45 and a 45 foot fence across the end
*Friday, January 18, 2013 at 6:29pm by Damon*

**algebra 1**

there are 60 second in a minute so 8x6=48 that means you can sort 48 in one minute. so if there are 45 minutes..... 45 x48=2160 your answer is 2160
*Thursday, October 3, 2013 at 11:56pm by celina*

**Math**

Using distance = rate x time 105t = 45(t+4) 105t = 45t + 180 60t = 180 t = 3 distance covered by each = 105(3) = 45(7) = 315 miles
*Wednesday, March 5, 2014 at 9:56pm by Reiny*

**chemistry**

Is that 0.050 M acetic acid? Let HAc stand for CH3COOH. You want pH = 3.80, convert that to (H^+) by pH = -log(H^+). Ka = (H^+)(Ac^-)/(HAc) Substitute (H^+),(Ac^-), and Ka into the Ka expression and solve for (HAc). Then substitute into the dilution equation to finish. m1C1 = ...
*Friday, December 2, 2011 at 10:04pm by DrBob222*

**chemistry**

To 160.0 mL of a buffer solution containing 0.250 M ammonia and 0.100 M ammonium chloride, 20.00 mL of 1.00M HClO4 are added. a) Calculate the pH of the new solution. b) What becomes the pH if another 20.00 mL of the same acid solution is added?
*Friday, February 15, 2013 at 10:49am by faizer*

**Math**

p = 2(width+length) = 2(x+4+x) = 2(2x+4) = 4x+8 s = p/4 = (4x+8)/4 = x + 2 94 = x(x+4) + (x + 2)^2 94 = x^2 + 4x + x^2 + 4x + 4 94 = 2x^2 + 8x + 4 2x^2 + 8x - 90 = 0 x^2 + 4x - 45 = 0 (x+9)(x-5) = 0 x = 5 rectangle is 5x9; p=28 a=45 square = 7x7; p=28 a=49 45+49 = 94
*Monday, October 24, 2011 at 8:48pm by Steve*

**Physics**

Assume a thermal equilibrium temp. T and find the heat absorbed by ice (say Q1)to raise its temp.from -35 deg. to T deg. Similarly, find heat released by water (say Q2) when its temp. lowers from 45 deg. to T deg. Putting Q1 = Q2 will give you T in deg. C. Note: Do not forget ...
*Tuesday, July 31, 2012 at 8:09pm by Ajayb*

**Chemistry**

I don't think it is but I've not thought about it until 30 seconds ago. One CAN do the titration with a pH meter BUT we don't know the base concn or the acid concn. We using the half-way point to the equivalence point, we are using pH = pKa + log (base)/(acid) and at the ...
*Monday, May 3, 2010 at 12:19am by DrBob222*

**Science**

What ar the 4 componets that effect the earths climate? How does Carbon and Nitrate effect humans and the enviroment?
*Wednesday, January 20, 2010 at 9:03pm by Ramandeep *

**Physical Geology**

What is one thing that humans get from each of the spheres? The spheres are the biosphere, atmosphere, hydrosphere, and lithosphere.
*Wednesday, March 25, 2009 at 3:57pm by James*

**English**

What word is being modified by the prepositional phrase? The monkeys ran from the sound of humans? Is it sound?
*Monday, February 4, 2013 at 5:46pm by Emily*

**Statistics**

a) In a normal distribution, the mean = median = mode. What percentage are below the median? Z = (score-mean(/SD Calculate the Z score for b. Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion related ...
*Wednesday, May 4, 2011 at 7:55pm by PsyDAG*

**HS Calculus**

no. y = √(2x) = (2x)^(1/2) y' = (1/2)(2x)^(-1/2)(2) = 1/√(2x) when x=2, y = 2, y' = 1/2 so the tangent line is y = (1/2)x + b which at (2,2) is 2 = (1/2)(2) + b b = 1 so the tangent equation is y = (1/2)x + 1 the normal would have slope of -2 so at (2,2) 2 = -2(2...
*Tuesday, November 25, 2008 at 8:16pm by Reiny*

**physics**

A rectangular loop of side 8cm and 2cm with a smal cut is movg out of uniform magnetic field of magnitude O.3t directed normal to d loop .wat is d emf developed acros d cut if d velocity of d loop is 1cm in a directed normal to d 1) longer side,2)short side of d loop ?for how ...
*Wednesday, December 7, 2011 at 10:22pm by anjan*

**math**

no try with the smallest possible sum 1+2+3+4 .. 1+2+...+8+9 = 45 adding up the marbles in the first 9 boxes is 45, so we don't even have enough marbles to use the smallest numbers possible
*Thursday, June 17, 2010 at 9:42pm by Reiny*

**physics**

1200 rev/min = 20 rev/s = 12.57 rad/s Call that the angular speed, w. The centripetal acceleration is R*w^2. R is the 0.45 m radius. a = 0.45*(12.57)^2 = ___ m/s^2
*Tuesday, September 18, 2012 at 10:33am by drwls*

**testing and selection of dogs**

please check this for me thank you You're at the vet's office with your own dog. A breeder brings in a big crate containing a litter of five-week-old puppies. When you show an interest in the pups, the breeder encourages you to handle them. You soon discover that they're a ...
*Thursday, June 26, 2008 at 11:34pm by Anonymous*

**math**

Assume the smaller ball has a volume of 45. Since volume is proportional to r^3, and R = 3r, the larger V is 3^3 as big as the smaller v, or 27*45 = 1215. for the details, see below for the smaller ball, v = kr^3 with k=4pi/3 The larger ball with radius R=3r has volume V = kR^...
*Monday, February 6, 2012 at 8:45pm by Anonymous*

**Chemistry**

I could write a book on this but I don't have the time. Here is how you do acetic acid. The others are done the same way. CH3COOH + NaOH(for example) ==> CH3COONa + H2O So the pH at the equivalence point is determined by the hydrolysis of the salt. CH3COO^- + HOH ==> ...
*Monday, December 12, 2011 at 7:26pm by DrBob222*

**Pythagorean Theorem**

i was given this in class: Pythagorean Theorem a^2 + b^2 = c^2 1.) O = 30° & Φ = 60° 2.) O = 45° & Φ = 45° 3.) O = 0 ° How would you calculate the ratio for these sides/angles?
*Wednesday, July 23, 2008 at 11:52pm by ruby*

**physics**

85 + 45 cos 30 = 124.0 m horizontally 45 sin 30 = 22.5 m vertically The magnitude of the displacement is sqrt(124^2 + 22.5^2)
*Wednesday, October 29, 2008 at 8:22pm by drwls*

**precalc/trig**

y = -1 x = -8 tanθ = y/x = 8 arctan 8 = 82.87° = 1.45 θ = 1.45 + pi = 4.59 r^2 = 1+64 = 65 So, -8-i = (√65,4.59)
*Tuesday, November 29, 2011 at 11:27am by Steve*

**Math**

Pythagorean theorem: c ^ 2 = a ^ 2 + b ^ 2 c = sqrt ( a ^ 2 + b ^ 2 ) In this case : a = 45 b = 86 c = sqrt ( 45 ^ 2 + 86 ^ 2 )= sqrt ( 2025 + 7396 ) = sqrt ( 9421 ) = 97.062 km
*Wednesday, February 15, 2012 at 12:37am by Anonymous*

**physics**

how long to fall 2.45 m (1/2) 9.81 * t^2 = 2.45 t = .707 s how far did the horse go? 15 * .707 = 10.6 Jump when the horse is 10.6 m away.
*Sunday, September 23, 2012 at 7:56pm by Damon*

**chemistry**

The pH value you read at the half way mark is pKa. So if half way is pH = 4.80, then pKa = 4.80 and Ka = 10-4.80 = 1.58E-6
*Friday, May 9, 2008 at 9:47pm by DrBob222*

**Chemistry**

a. mols Na2CO3 = 5.3/106 = ? mols H^+ initially = ? x 2 M acid = mols/L soln = 2?/2 = x pH = -log(H^+) = xx b. mols NaOH = 5.3/40 = ? mols H^+ = same M acid = mols/L soln pH = -log(H^+)
*Saturday, September 29, 2012 at 5:04am by DrBob222*

**Chemistry**

a. pH = 8.87 8.87 = -log(H^+) Solve for (H^+), then pH + pOH = pKw = 14 You know pH and pKw, solve for pOH and pOH = -log(OH^-) which lets you solve for OH. b. This is a hydrolysis problem. You know OH^- from part a. That = (CH3COOH). c. Kb for CH3COO^- = (Kw/Ka for CH3COOH) (...
*Saturday, September 29, 2012 at 5:03am by DrBob222*

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