Thursday

May 28, 2015

May 28, 2015

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*