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April 2, 2015

Posts by katie


Total # Posts: 1,739

Chemistry
Calculate the molar mass of a diprotic acid. It reaches the endpoint of the titration with NaOH at 28ml. The initial concentration of NaOH is 0.09792. and the initial mass of the diprotic acid is 0.685g. I keep getting a molar mass of 500g/mol. but the options are all around ...
March 30, 2013

Chemistry
So you need to times the molarity by two?
March 30, 2013

Chemistry
Calculate the molar mass of a diprotic acid. It reaches the endpoint of the titration with NaOH at 28ml. The initial concentration of NaOH is 0.09792. and the initial mass of the diprotic acid is 0.685g. I keep getting a molar mass of 500g/mol. but the options are all around ...
March 30, 2013

Chemistry
How many mL of 12M HCl is needed to create 350mL of 0.125M HCl?
March 28, 2013

history
lol wut?
March 25, 2013

math
For the function f(p) an input of 3 yields an output value of 6. What value of p would you use to have f(5p) = 6?
March 24, 2013

Chemistry
K1 = 0.727 K2 = 12.1 T1 = 2000 T2 = 3000 Solve for the standard enthalpy of formation. They gave me the formula ln(K2/K1) = DeltaH /R (T2 - T1 / T1T2) The answer is supposed to be in KJ/mol and I keep getting 2.022 but its not right. I'm not sure what Im doing wrong
March 24, 2013

math
For the function f(p) an input of 3 yields an output value of 6. What value of p would you use to have f(5p) = 6?
March 22, 2013

Chemistry
A 50.0 mL sample of 0.10 M pyridine, C5H5N, is titrated with 0.2 M HBr. Calculate the pH to one decimal place when the following volumes of titrant have been added. 0.00 mL a) 0ml b)17ml c)25ml d)40ml
March 7, 2013

math
6^(2log(x)) = 8
March 5, 2013

math
Let 2^a = 5 and 2^b = 10. Using exponent rules, solve the equation in terms of a and b. 10^x =(1/64)
March 3, 2013

statistics
In a certain region, the mean annual salary for plumbers is $51,000. Let x be a random variable that represents a plumber's salary. Assume the standard deviation is $1300. If a random sample of 100 plumbers is selected, what is the probability that the sample mean is ...
February 25, 2013

statistics
the breaking distance of a Honda CRV can be approximated by a normal distribution, where the mean is 53 meters and the standard deviation is 3.8 meters. Let x be a random variable that represents a braking distance. Find the probability that a randomly selected braking ...
February 25, 2013

P Value Math Statistics
Find the P-value for the indicated hypothesis test with the given standardized test statistics, z. Decide whether to reject H0 for the given level of significance a. two-tailed test with test statistic z= -1.57 and a=0.04
February 24, 2013

statistics
In a normal distribution with mu = 25 and sigma = 3, what number corresponds to z = -3? is it 16, 18, or 20
February 24, 2013

Gen Math
A school dance has 228 students. There are 63 fewer girls than twice as many boys. How many boys and girls attended the dance?
February 24, 2013

Economics
A $90,000 investment is made. Over a 5 year period, a return of $30,000 occurs at the end of the first year. Each successive year yields a return that is $3,000 less than the previous year's return. If money is worth 5 percent, use a gradient series factor to determine the...
February 23, 2013

Finance
You plan to open a retirement account. Your employer will match 50 percent of your deposits up to a limit on the match of $2500 per year. You believe the fund will earn 12 percent per year over the next 30 years, and you will make 30 deposits of $5000, plus 50 percent employer...
February 23, 2013

college algebra
driving along a crowded freeway you notice that it takes a time to go from one mile marker to the next. when you increase your speed by 8.4 mi/hr the time to go one mile decreased by 14 seconds. What was your original speed?
February 21, 2013

Chemistry
How many grams of solute are present in 875 mL of 0.180 M KBr?
February 20, 2013

Chemistry...
The oxygen gas emitted from an aquatic plant during photosynthesis is collected over water at a temperature of 25 degrees celsius and a total pressure of 762 torr. What is the partial pressure of the oxygen gas? What formula do I need to use?
February 20, 2013

Need help asap**
Oh goodness. I'm deeply sorry. I wasn't trying to make anyone angry or annoyed.
February 20, 2013

Need help asap**
The oxygen gas emitted from an aquatic plant during photosynthesis is collected over water at a temperature of 25 degrees celsius and a total pressure of 762 torr. What is the partial pressure of the oxygen gas? What formula do I need to use?
February 20, 2013

report
thank you
February 19, 2013

report
What are key findings? I have to include this in a lab report. Thank you for any help
February 19, 2013

Physics
A plant falls from the windowsill of an apartment in a very tall building. If the floor of your apartment is 12.19 m above the ground, and it takes the plant 0.2580 seconds to cross your 9 ft window, from what height did the plant fall? ? m Explain what would be different if ...
February 19, 2013

math
14=2/3(9y-15)
February 18, 2013

science
How do I make an acrostic that has to do with the word Wavelength?
February 17, 2013

Statistics
These are the only ones that I am having problems with. Please help.. 8.You are given the sample mean and the sample standard deviation. Use this information to construct the 90% and the 95% confidence intervals for the population mean. Interpret the results and compare the ...
February 17, 2013

Chemistry
On a 10.5 ounce bag of potato chips, the manufacturer states that the single serving is one ounce, which is equivalent to 150 calories. How many kilojoules are in this bag of potato chips? Is it 6.5898kJ?
February 9, 2013

Chemistry
Ooops, sorry Linda.
February 9, 2013

Chemistry
On a 10.5 ounce bag of potato chips, the manufacturer states that the single serving is one ounce, which is equivalent to 150 calories. How many kilojoules are in this bag of potato chips? Is it 6.898 kJ?
February 9, 2013

science
Newton’s Second Law of Motion is expressed as F = ma. If you are pushing a lawn mower in your backyard and suddenly double the pushing force, what will happen to the lawn mower's rate of acceleration? The mass of the lawn mower is constant. A. The acceleration will ...
February 8, 2013

math
Jill is correct because angels is on any shape
February 5, 2013

math
thanks
February 5, 2013

math
I got (9,28) is that right.
February 5, 2013

math
solve using substitution y=4x-8 y=2x+10
February 5, 2013

Physics
According to Anna, on Earth, Bob is on a spaceship moving at 0.8c towards Earth, and Carl, a little farther out, is on a spaceship moving a 0.9c towards Earth. According to Bob, how fast is Carl moving relative to Earth? (a) According to Bob, how fast and in what direction is ...
February 4, 2013

social studies
Which of the following types of information are people LEAST comfortable revealing to professionals? a. emotional b. financial c. legal d. medical
February 4, 2013

Chemistry 3A
You want to make the following buffer: 5% glucose, 100 mM tris and 10 mM EDTA in a final voume of 300ml. Your stock solutions are 20% glucose, 1M tris and 0.5M EDTA. The diluent is distilled water. Determine how much of each you will add to make the desired buffer. I know this...
February 1, 2013

Math
Calculate how long a de-orbit burn must last in minutes and seconds to achieve the Shuttle’s change in altitude from 205 miles to 60 miles at perigee.Use the equations and conversions provided below in method 1 or method 2 to find the required burn time
February 1, 2013

penn foster
im trying to finish these classes soon so i can start college, but honestly they are too complex. and i NEED HELP!!!! I have 1-5 done. 6. In the Mongol Empire, the plague A. provided new oppurtunities for territorial expansion B.ended further expansion C. had no effect, ...
January 30, 2013

physics
Bob and Bob Jr. stand at open doorways at opposite ends of an airplane hangar 25 m long. Anna owns a spaceship, 40 m long as it sits on the runway. Anna takes off in her spaceship, then swoops through the hangar at constant velocity. At precisely time zero on both Bob's ...
January 30, 2013

Physics
Bob and Bob Jr. stand at open doorways at opposite ends of an airplane hangar 25 m long. Anna owns a spaceship, 40 m long as it sits on the runway. Anna takes off in her spaceship, then swoops through the hangar at constant velocity. At precisely time zero on both Bob's ...
January 29, 2013

College Algebra
V= 4/322/7r^ 3 v= 4/3 *22/7*(6 1/4 in)^3 v=3/4 * 22/7 * 15625/64 v= 1023.065476 how to change to a mix-number?
January 27, 2013

College Algebra
I like to change this(1023.065476) whole number into a mix-number to find the volume of the sphere (6 1/4 in) using 22/7 for pie.
January 27, 2013

geometry
if measure of angle SUT=3x+6 and measure of angle RUS=5x-4, find measure of angle SUT
January 27, 2013

science
Lipids: Not a polymer because _ __x's energy than carbs Saturated= Unsaturated= Nucleic Acids: RNA= DNA= Carbohydrates: Building blockks
January 26, 2013

science
I think it's about 20.
January 26, 2013

science
How many amino acids are there in protien
January 26, 2013

Math
I am a 4digits number with 6 hundreds and 5ones.The sum of all my digits is 15 .What number am I
January 25, 2013

Math 7A
Use the function rule, y = 2x + 5, to find the values of y when x = 1, 2, 3, and 4. Write the answers as ordered pairs that would be used to graph the function. can someone help me i'm stuck on this question
January 21, 2013

alg/trig
The first thing you want to do is get rid of x in the denominator, because that simplifies things quite a bit. Think of the easiest common denominator between 9/x and 9/(x-2), which would be x(x-2). You know that x-2/x-2 = 1, regardless of the value of x; the same with x/x, so...
January 21, 2013

Math
10^5.4 = 251188.6432 = 2.5 X 10^5 You can just plug this in the calculator. I think it's two significant figures
January 21, 2013

Physics
t(Earth) = t(satellite) / (square root) 1 - (v/c)^2 = t(satellite) / (square root) 1 - [ (3.9 x 10^3) / (3x 10^8)^2 ] = (1 - 1.7 x 10^-10)^ - 1/2 [ t(satellite) ] t(Earth) = (1 + 8.5 x 10^-11) [ t(satellite) ] GMEarth = (6.67 x 10^-11 N x m^2/kg^2) (5.98 x 10^24 kg) = 4.0 x 10...
January 21, 2013

Physics
A GPS satellite orbits at an altitude of 2.0 x 10^7 m and a speed of 3.9 x 10^3 m/s, Earth’s radius is 6.4 x 10^6 m, and a point at its equator has tangential speed of 460 m/s, By approximately what fraction must the time be adjusted to account for both regular/speed-...
January 21, 2013

Math
7 snow days divide by the the amount of days in december which is 31 days (7/31) x 100 = 22.5 %
January 21, 2013

math
How would I write 2 inequalities that describe in basketball that 2 points = field goal and 1 point = free throw and I have scored at least 3 points in every game this season and 15 points for the most points in one game? Please Explain! I don't understand.
January 21, 2013

Math
Use the function rule, y = 2x + 5, to find the values of y when x = 1, 2, 3, and 4. Write the answers as ordered pairs that would be used to graph the function.
January 18, 2013

Physics
thank you
January 18, 2013

Physics
The kinetic energy of a proton is half its internal energy. What is the proton's speed? Kinetic energy is (Yu - 1) (mp) (c)^2 = 1/2 (mp) (c)^2 Yu = 1.5 Yu = 1/(square root) 1 - (u/c)^2 1/(square root) 1 - (u/c)^2 = 1.5 u= 0.745c How do I solve for u? I'm extremely ...
January 18, 2013

trig proofs
cotx+tanx=secx+cscx
January 15, 2013

Math
Number Sense How can you use 4 x 7 to find 8 x 7? Find the product.
January 8, 2013

Calculus II
ok thank you very much. Happy New Year
December 30, 2012

Calculus II
Find x and dx using trigonometric substitution of (integral) square root of 4x^2 - 9 divide by x x = 2/3 sec x dx = 2/3 tan x dx Is this right so far?
December 30, 2012

Calculus II
ok, thank you very much. Happy New Year
December 30, 2012

Calculus II
Okay then, is this the final answer = (5-x)(3e^3x) + (integral) -- (1/3)e^3x = (5-x)(3e^3x) + (1/9)e^3x + C
December 30, 2012

Calculus II
Integrate using integration by parts (integral) (5-x) e^3x u = 5-x du = -dx dv = e^3x v = 3e^3x I wonder if this is right so far. = uv - (integral) v du = (5-x)(3e^3x) - (integral) (-3e^3x) =(5-x)(3e^3x) + (integral) (3e^3x) = (5-x)(3e^3x) + 9e^3x + C
December 30, 2012

Chemistry
Question: A solution of Silver nitrate, AgNO3, contains 1.08 grams in 250 cm3. What is its molarity? Solution: Molar mass of Silver nitrate = 108 g/mole. n(AgNO3) = 1.08 grams of AgNO3 x 1 mole of AgNO3108 grams AgNO3 = 0.01 mole. Number of moles in 1 dm3 = 0.01 mole x 1000/...
December 30, 2012

Physics
11 4 n + B ----> ___?___ + He 2 7 8 A. Li or B. Li 235 4 Pa ------> ___?___ + He 91 2 A.230 or B. 231 Ac Ac
December 18, 2012

math
the expression a^2(b^3)/a^-4(b^2) is equivalent to 1 a^6/b^5 2. b^5/a^6 3. a^2/b 4. a^-2(b^-1)
December 18, 2012

Physics
A car and a bus are moving down a hill, the bus is 3X heavier than the car and the speed of the car is 3X faster than the bus. Compare their momentum and K.E.
December 17, 2012

Physics
Who originally designed the planetary model of an atom? Bohr or Rutherford
December 17, 2012

physics
Maxwell's equations proved that a. Light is a mechanical phenomena b. Light is a chemical phenomena c. Light is a phenomenal phenomena d. Light is an electromagnetic phenomena I think the answer is either a or d. But I'm pretty sure its d Thank you for any help and ...
December 16, 2012

8th Grade English
My teacher for my english class at school marked off for these questions and said I could redo it and turn it in tomorrow. I am for sure I did these right. Here are the questions. Underline the verb in the parentheses that agrees with the subject. 1. In the Northern Hemisphere...
December 11, 2012

Physics, asap please
If a sphere and paper are dropped from 10 meters and the sphere hit the ground in 1.4 seconds and the paper hit in 2 seconds, why did the impact time in case of the piece of paper change in comparison to the sphere? A. a=(Wt-R)/m;a=g B. a=(Wt-R)/m;a>g C. a=(Wt-R);a<g D. ...
December 10, 2012

Science
What is the Mass number and Atomic number for the element B (Boron)? It is for a homework sheet and I am blanked out. I forgot my text book. Can anyone help me?
December 10, 2012

Chemistry 3A
You have three moles of oxygen and hydrogen. And 1 mol of aluminum as well as one mole of aluminum hydroxide
December 10, 2012

Chem
PV = nRT - Change pressure to atm - Change grams of oxygen to mol of oxygen for n - Change degrees in celsius to kelvin which in this case is 273 K. Write all of the units of P, n, R and T and it will cancel out to get liters for volume
December 10, 2012

Physics
If a sphere and paper are dropped from 10 meters and the sphere hit the ground in 1.4 seconds and the paper hit in 2 seconds, why did the impact time in case of the piece of paper change in comparison to the sphere? A. a=(Wt-R)/m;a=g B. a=(Wt-R)/m;a>g C. a=(Wt-R);a<g D. ...
December 10, 2012

Physics
If a sphere and paper are dropped from 10 meters and the sphere hit the ground in 1.4 seconds and the paper hit in 2 seconds, why did the impact time in case of the piece of paper change in comparison to the sphere? A. a=(Wt-R)/m;a=g B. a=(Wt-R)/m;a>g C. a=(Wt-R);a<g D. ...
December 9, 2012

Physics
Pretend the hot brick extracts heat from the cold brick and becomes hotter. Would this violate the Law of Conservation of Energy?
December 9, 2012

Physics
If a sphere and paper are dropped from 10 meters and the sphere hit the ground in 1.4 seconds and the paper hit in 2 seconds, why did the impact time in case of the piece of paper change in comparison to the sphere? A. a=(Wt-R)/m;a=g B. a=(Wt-R)/m;a>g C. a=(Wt-R);a<g D. ...
December 9, 2012

Physics
A rapidly changing magnetic field in any region of space induces a rapidly changing A.Magnetic field or B.Electric field? which in turn induces a rapidly changing A.Magnetic field B.Electric field?
December 8, 2012

Physics
If your own mass is 70kg and the mass of a building is 4x 10^6kg and the distance between you and the building is 1m, in comparison to your own weight, estimate the force of attraction between you and the building.
December 8, 2012

Physics
A car weighing one ton is moving at 50km/hr and a truck weighing two tons is moving at 25km/hr. Both are moving in the opposite direction, which has more momentum? I think they are the same, but want to make sure
December 8, 2012

Physics
While stationary on a boat you are measuring the time it takes for the coin to leave your hand and hit the water.In order to measure that time you are tuned to the sound of the coin hitting the water. You know that it takes 5.5 seconds for the coin to leave your hand and hit ...
December 8, 2012

Physics
If one drops a sphere and a piece of paper from the same height of 10 meters(H=10m) and the sphere hits the ground in 1.4 secs and the paper in 2 secs, what is the gravity associated with the sphere and why did the impact time change between the paper and sphere?
December 8, 2012

physics
.436
December 6, 2012

social studies
what is the question to usa studies weekly 9
December 4, 2012

science
What does it mean to be a successful organism? Is bacteria the most successful organisms on earth?
November 29, 2012

College Physics 1
.767s
November 28, 2012

ENGLISH
hi ive been reading a book called, the berlin boxing club, and one of my hw assignments say i need to find 10 quotes in the book and im having trouble finding them. can u please help me? :)
November 27, 2012

english
hi ive been reading a book called, the berlin boxing club, and one of my hw assignments say i need to find 10 quotes in the book and im having trouble finding them. can u please help me? :)
November 27, 2012

College Physics
Suppose a planet is discovered that has the same total mass as the Earth, but half its radius. Calculate the acceleration due to gravity on the surface of this planet.
November 27, 2012

physics
The range of human hearing extends from approxmately 20 HZ to 20 000 HZ. Find the wavelenghts of these extremes when the speed of sound in air is equal to 343 m/s. A dolphin is 25 degrees C sea water emits a sound directed toward the bottom of the ocean 150 m below. How much ...
November 21, 2012

algebra
are you factoring? we are doing that right now if you need help
November 21, 2012

social studies
what religion was part of the Song Dynasty ?
November 18, 2012

reading
"It's raining cats and dogs" is an idiom for "it's raining really hard."
November 8, 2012

Physics
A 60 mm mortar round is capable of being launched at 540 km/hr. If a target is located at a distance of 0.6 km and the mortar takes 7.5 s to reach the target, at what angle must the launcher be set to hit the target?
November 7, 2012

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