Wednesday
April 1, 2015

Posts by Paula


Total # Posts: 305

chemistry help
What mass of ammonium chloride must be added to a 0.500 L solution of 0.250 M ammonia to make a buffer with a pH of 9.26? Kb (NH3) = 1.8 × 10–5?
March 30, 2015

chemistry
What is the total change in entropy when 10.0 g of ice melts at 25.0°C? DHfus = 6.01 kJ/mol The answer is 1.03 J/K but idk how to find it.
March 29, 2015

chemistry
Hydroxyapatite is the main mineral component of bone. How many grams of hydroxyapatite will dissolve in 1.00 L of H2O? Ksp = 2.34 × 10–59; Molar mass = 502.3 g/mol? I keep getting 5.83x10^-18 g but the answer is supposed to be 4.35x10^-5 g. I don't understand why
March 29, 2015

Chemistry
You would use m1v1=m2v2 so (25 mL)(0.1 M) = ( x mL)(0.025 M). You would solve for x mL
March 29, 2015

chemistry
Would I use the Henderson-hasselbalch equation? And what would I do after that?
March 28, 2015

chemistry
What mass of ammonium chloride must be added to a 0.500 L solution of 0.250 M ammonia to make a buffer with a pH of 9.26? Kb (NH3) = 1.8 × 10–5?
March 28, 2015

chemistry
What is the total change in entropy when 10.0 g of ice melts at 25.0°C? DHfus = 6.01 kJ/mol The answer is 1.03 J/K but idk how to find it.
March 28, 2015

chemistry
Calculate the pH of a buffer which contains 0.0500 M pyruvic acid and 0.0450 M sodium pyruvate. (The Ka of pyruvic acid is 4.1 × 10–3)
March 27, 2015

Medical billing and Coding
What is defined as improper behavior or billing practices that result in financial gain? I have looked all through the text and cannot find the answer.
March 26, 2015

calculus
Find the intervals on the x-axis on which the function f(x) is increasing and those which it is decreasing, where f(x) = (x)/(x^2+1) I differentiated and got f'(x)=(x^2+1) -(x)(2x) all over (x^2+1)^2 But I don't know what to do now...
March 25, 2015

chemistry help
0.0025?
March 23, 2015

chemistry help
If the standard calcium carbonate solution is 100 ppm and 25 mL of solution is used for the standardization, calculate the approximate volume of 2mM EDTA solution needed to reach the end point of the titration. I know to use M1V1=M2V2 but need help converting units of ...
March 23, 2015

chemistry
If a solution of lead iodide has [I-] = 1.1x10-4 M, what is the lead(II)ion concentration at equilibrium?
March 16, 2015

calculus
differentiate y = 2^3x^2 read as two to the 3x squared power
March 4, 2015

chemistry
Suppose that the reaction of Fe3+ and SCN- produces Fe(SCN)2 (+). 5.00mL of 2.0mM Fe3+ is mixed with 5.00 mL of 2.0mM SCN-. The student finds the equilibrium concentrations of Fe(SCN)2(+) to be 0.3mM. 1.) What is the initial number of moles of each species present? 2.) What is...
February 23, 2015

Math 110
(a) g(x)=cos(􏰀x/(x^2 +9)) (b) f(x)=x^(5/3) −x^(2/3)
February 9, 2015

Math 110
Find intervals of increase/decrease and classify all critical points of (a)g(x)=cos(􏰀x/(x2 +9)) (b) f(x)=x5/3 −x2/3
February 9, 2015

Math
Let f(x) = 2x + 1 − sin(x), how many roots does f(x) have in the interval [−π, π]? Use the next steps to prove that it has only one root. a) Use the Intermediate Value Theorem to show that f(x) has at least one root. (b) Explain why f(x) is increasing on ...
February 9, 2015

calculus
Find the value of the limit. lim ã(x+4) - 2 divided by x x->0 The 2 is outside of the square root. The answer is supposed to be 1/4 but I keep getting 0/0 no matter how many times I redo the algebra.
February 3, 2015

physics
A skier of mass 74.6 kg is pulled up a slope by a motor-driven cable. How much work is required to pull the skier 63.3 m up a 39.0◦ slope (assumed to be frictionless) at a constant speed of 2.0 m/s? The acceleration of gravity is 9.81 m/s 2 . Answer in units of J
January 29, 2015

chemistry help
What are the differences in measuring the molar mass using freezing point depression between studying ionic solids and molecular solids?
January 24, 2015

chemistry
A sample of 10.00g of a solid unknown was dissolved in 25.00g of water. Assuming that pure water freezes at 0.0°C and the solution freezes at -5.58°C, what is the molal concentration of the solution? What is the molar mass of the solid? Show your calculation. I got ...
January 24, 2015

Spanish 3 Homework
Oh, I'm sorry! I forgot to mention that in my previous posts; we're learning "single object pronouns".
January 22, 2015

Spanish 3 Homework
Also, would it be okay if you checked these 4 I got today to practice? It's dealing with the same thing as before. 1.) (you all) Don’t cook the food! My answer: No cocine la comida! 2.) (friend) Don’t cook the food for me! My answer: No cocine la comida para m&...
January 22, 2015

@SraJMcGin Spanish 3 Homework
Hi! Okay so I got a little confused for #4 and #5. So for #4 it would be "Vamos a estudiemos!" or just "Estudiemos"? And then for #5 is it "Vamos a estudiárselo"?
January 22, 2015

Spanish 3 Homework
Hi! Can someone check these for me to see if I'm doing them right? Thank you! Directions Re-write the commands in Spanish using object pronouns. Also, the words in parentheses are saying who you are talking to. 1.) (sister) Wash the dishes for me! My answer: Lavaba los ...
January 22, 2015

Chemistry
A sample of oxygen gas occupies a volume of 3.84 L at 269. K. What volume will the sample occupy at 486. K?
December 6, 2014

Chemistry
Calculate Delta H for the following equation: Zn(s) + 2H+(aq) = Zn2+(aq) + H2(g)
November 28, 2014

Math
One box holds 16 crayons.Another box holds 24 crayons.Write a sentence using words that compares the crayons in the two boxes.
November 19, 2014

Science
Susie decides to pull on a 1.5kg toy (horizontally) with a force of 25N. Friction acts against the toy with a force of 6n. What is the acceleration of the toy?
November 4, 2014

Calculus
A rocket is fired vertically into the air at the rate of 6 miles/min. An observer on the ground is located 4 miles from the launching pad. When the rocket is 3 miles high, how fast is the angle of elevation between the rocket and the observer changing? Specify units.
November 2, 2014

algebra 1
princess leia is a very good math student. Her average math grade was a 95 on her 15 tests. If Darth Mangham decides to drop her lowest grade, write an expression to determine her new test average.
October 3, 2014

public speaking
When preparing an outline for a speech which of the below is NOT a part of the speech outline
September 28, 2014

public speaking
Medium that carries message signals from senders to receivers of communication is
September 28, 2014

Chemistry
What mass of ammonium nitrate is require to produce 145L of N2O at 2850 torr and 42 degree celcius
September 28, 2014

Algebra
Solve 9 - c <2 or -3c > 15 My answer is 7 or -5
September 22, 2014

Algebra
Solve 5<x-2<11 My answer is 7<x<13
September 21, 2014

Algebra
Choose them compound inequality that represents all real numbers that are less then -3 or greater than or equal to 5.
September 17, 2014

Algebra
U = 1,2,3,4,5,6,7,8,9,10 Q=3,6,9 What is Q prime? My answer is 1,2,4,5,7,8,10
September 16, 2014

Algebra
Thank you
September 16, 2014

Algebra
Sis the set of prime numbers that are less than 15. My answer is 2,3,5,7,11, and 13
September 16, 2014

Algebra
What inequality represents the verbal expression all real numbers less then 69? My answer is x<69
September 14, 2014

physics
Scientists want to place a 3300 kg satellite in orbit around Mars. They plan to have the satellite orbit a distance equal to 2.2 times the radius of Mars above the surface of the planet. Here is some information that will help solve this problem: mmars = 6.4191 x 1023 kg rmars...
September 13, 2014

Algebra
Thank you
September 13, 2014

Algebra
solve and show steps 6=x+2/3
September 13, 2014

Algebra
3(x-7)-x= 2x-21 Does this equation have infinitely many solutions My answer is yes.
September 13, 2014

Algebra
4y+8=6y+3 Is the expression true,false,or open? My answer is true = 5/2
September 13, 2014

Music
What is the vertical line at the end of a measure called?
September 11, 2014

Music
if you add up the durations from left to right on any level of a note tree you end up with a what?
September 11, 2014

Math
I don no andedte
September 9, 2014

Math
In above triangular prism,ab=3cm,ac=4cm,bc=5cm and cd12 cm,show that triangle ABC is a right-angled triangle
September 6, 2014

3D Modling
What are the preset views in Blender Software?
August 31, 2014

Physics
David, who is 65 kg, is driving his car at a speed of 25 m/s. He sees a dog crossing the road and so he steps on the brake to avoid hitting it. His seatbelt brings his body to a stop in 0.4 s. What magnitude of force does the seatbelt exert on him?
August 25, 2014

Physics
02. Comic-strip hero Superman meets an asteroid in outer space and hurls it at 800 m/s, as fast as a bullet. The asteroid is a thousand times more massive than Superman, yet in the comic strip, he remains stationary after releasing the asteroid. Say, his mass is 107 kg, what ...
August 25, 2014

math
compare write >or< for 2,854,376 to 2,845,763
August 21, 2014

finance
A quaint but well established cafe shoppe in the new hot cafe wants to build a new cafe for increased capicity it expect sales are $800,000.00 for the first 5 years, direct cost including labor and material 50% for new cafe will be totaled at $750,000.00 which will depreciate ...
August 17, 2014

SAT math
A family of 2 parents and 4 children is eating lunch at a rectangular table with 2 chairs on each side and one chair on each end. In how many ways can they be arranged if the two parents sit in the two end chairs? a. 12 b. 30 c. 36 d. 48 e. 720
April 5, 2014

Algebra
first set up a regular proportion: 5a/x = 20 ohms/ 25 ohms Because the problem says the current varies inversely you would flip only one side of the proportion: 5A/xA = 25 ohms/ 20 ohms cross multiply: 100 = 25x ohms Divide by 25: x = 4A
March 1, 2014

math
208 square root to nearest hundredth.
February 24, 2014

math
255 square root to the nearest hundredth.
February 24, 2014

math
130 square root to the nearest hundredth.
February 24, 2014

Math
X^ -3 = 216 How do you find x?
December 18, 2013

information technology
How does the organizational strategy drive the IT strategy?
November 29, 2013

SAT math
The slope of the line passing through p and q is -3/5. What is the value of x? P(1,4) Q(x,1)
November 2, 2013

Math
The slope of the line passing through p and q is -3/5. What is the value of x? P(1,4) Q(x,1) I got 6 but Im not sure
November 2, 2013

SAT MATH
if x^2 - y^2 = 77 and x + y=11 what is the value of x?
October 12, 2013

Math
if 5x + 7y = 18 and 2x - 4y = 6, what is the value of 7x + 3y? a. 7 b. 12 c. 19 d. 24 e. 31
October 5, 2013

math
if the sum of 7 integers is even, at most how many of these integers could be odd? a. 3 b. 4 c. 5 d. 6 e. 7
October 5, 2013

Earth Science
thanks!
September 29, 2013

Earth Science
A contour (topographic) map indicates that a stream is flowing across a landscape. If the stream has a constant volume, where on the map would the stream most likely have the highest velocity? a. As the stream moves across several closely spaced contour lines b. as the stream ...
September 29, 2013

Math
if the line containing the points (a,3) and (b,2) has a slope of 1/7, then a-b=
September 14, 2013

science
2 students were testing the amount of fertilizer that would best promote the growth of strawberries in a garden. What is an unavoidable error they can make during this process?
August 29, 2013

Biology
. 2 students were testing the amount of fertilizer that would best promote the growth of strawberries in a garden.List an unavoidable source of experimental error
August 22, 2013

biology
identify and describe how organism could respond to an external stimulus
August 14, 2013

Trig
Given that csc θ = -4 and tan θ > 0, find the exact value of a. x b. sin θ c. cos θ d. r e. sec θ f. cot θ
August 7, 2013

Trig
Given that tan θ = - (√3/8) and θ is in QII, find the exact value of a. r = b. csc θ c. cos θ d. cot θ
August 7, 2013

Trig
Given that cos θ = 5/13 and θ is in QIV, find the exact value of a. y b. sin θ c. sec θ d. tan θ
August 7, 2013

Math
thanks
August 5, 2013

Math
At Uriah's coffee shop, the amount of ground coffee beans left in stock on a given days a function of the amount of coffee sold that day. If "c" is the number of cups of coffee sold, and "z(c)" is the number of ounces of ground coffee left in stock, ...
August 5, 2013

SAT math
In the figure shown above (its a right triangle), points G, H, and I in the xy-plane have coordinates of (0,2), (2,8) and (8,n), respectively if GH=HI what is the value of n?
August 5, 2013

Algebra
True or False and please explain so that I can understand. 1. The rationalized form of 125 over the square root of 14 involves no radicals. 2. The radical square root of 4 cannot be used to rationalize the denominator of any radical number.
August 5, 2013

POL 201 American National Government
under the budget reform act the Presidency may defer spending appropriated funds if congress fails to act within 45 days of being notified about the deferment (b) may never dfer spending appriopriated funds (c) spend more that was allocated (d) does not need to request ...
July 28, 2013

Algebra
True or False. The fifth root of a positive integer is sometimes irrational. Please give an example or a counterexample so that I can understand it fully.
July 26, 2013

Math
True or False. The value of the square root of 16 is greater than the cube root of 29.
July 21, 2013

Algebra
True or False. 1. If the radicand is a multiple of a perfect square number, then the radical is not in its simplest form. 2. The value of the cube root of -1/8 is not a real number because the radical is negative. 3. The fifth root of a negative number is not a real number.
July 19, 2013

chemistry
When 30.0g of aluminum reacts with HCl, how many grams of aluminum chloride are formed? Al + HCl --> AlCl3 + H2
July 15, 2013

chem
Calculate the mass in grams of carbon needed to produce 160 g of CO2 in burning: C + O2 --> CO2
July 15, 2013

Math
Are these true or false? 1. If s is negative, then the square root of s^2 is -s. 2. If r is positive, then the square root of r^2 is -r. 3. If q is negative, then the square root of q^2 is q. 4. If p is positive, then the square root of P^2 = p. If possible, kindly give me ...
July 15, 2013

Lincoln College Of New En
A survey by Men’s Health magazine stated that 14% of men said they used exercise to reduce stress. Use a = 0.10. a random sample of 100 men was selected and 10 said that they used exercise to relieve stress. Use the P –value method to test the claim. Could the ...
April 26, 2013

Lincoln College Of New En
it has been found that 85.6% of all enrolled college and university students in the U.S. are undergraduates. A random sample of 500 enrolled college students in a particular state revealed that 420 of them were undergraduates. Is there sufficient evidence to conclude that the ...
April 26, 2013

Lincoln College Of New En
The percentage of physicians who are women is 27.9% in a survey of physicians employed by a large university health system, 45 of 120 randomly selected physicians were women. Is there sufficient evidence at the 0.05 level of significance to conclude that the proportion of ...
April 26, 2013

Lincoln College Of New En
the Old Farmer’s Almanac stated that the average consumption of water per person per day was 123 gallons. To test the hypothesis that this figure may no longer be true, a researcher randomly selected 16 people and found that they used on average 119 gallons per day and s...
April 26, 2013

Lincoln College Of New En
the average 1-ounce chocolate chip cookie contains 110 calories. A random sample of 15 different brands of 1-ounce chocolate chip cookies results in the following calorie amounts, at the a = 0.01 level, is there sufficient evidence that the average calories contents is greater...
April 26, 2013

math
Find the distance around the track if x=20 feet and y=25 feet
April 21, 2013

STATISTICS
the percentage rates of home ownership for 8 randomly selected states are listed below. Estimate the population variance and standard deviation for the percentage rate of home ownership with 99% confidence. 66.0 75.8 70.9 73.9 63.4 68.5 73.3 65.9
April 19, 2013

STATISTICS
A random sample of stock prices per share (in dollars) is shown. Find the 90% confidence interval for the variance and standard deviation for the prices. Assume the variable is normally distributed.
April 19, 2013

STATISTICS
the percentage rates of home ownership for 8 randomdomly selected states are listed below. Estimate the population variance and standard deviation for the percentage rate of home ownership with 99% confidence. 66.0 75.8 70.9 73.9 63.4 68.5 73.3 65.9
April 17, 2013

Lincoln College Of New En
26 Gasoline Mileage for Autos and Trucks – Of the top 10 cars and trucks based on gas mileage, 4 are Hondas, 3 are Toyotas, and 3 are Volkswagens. Choose one at random. Find the probability that it is Japanese, Japanses or German or not foreigh.
April 6, 2013

chemistry
draw particle diagrams that account for the fact that 2 volumes of nitric oxide gas react with 1 volume of oxygen gas to form 2 volumes of product with no leftover gas
April 5, 2013

Lincoln College Of New En
How man 4 letter code words can be made using the letters in the word pencil if repetitions are permitted?
April 4, 2013

Pages: 1 | 2 | 3 | 4 | Next>>

Members