Monday
April 27, 2015

Posts by ryan


Total # Posts: 981

chemistry
Calculate the weight in grams of potassium hydrogen phthalate (KHP, KHC2H3O2, MW 202.2 g/mole) required to neutralize 25.00 ml of 0.1 M NaOH solution.
April 15, 2015

chemistry
Describe in detail how you would prepare 500 ml of 0.1 M HCl from 6 M HCl stock solution.
April 15, 2015

chemistry
Describe in detail how you would prepare 1000 ml of 0.1 M NaOH from 6 M of NaOH stock solution.
April 15, 2015

Maths help
W= rad/s and a = 0.6. My mistake Very sorry reiny it's just that I'm in desperate need of help and no one Is answering my questions. Could you please help me?
April 12, 2015

Maths help
The angle of a rotating shaft turns in t seconds is given by theta= ω+1/2at^2 and it is given that ω=3 2 rad/s and α=0.6 rad/s to complete θ=4 radians. Determine the time taken to complete θ=4 radians.
April 12, 2015

Maths help
Two resistors in series, R1 and R2, have a total resistance of 1,600 ohms. The resistance of R2 is 560 ohms less than twice R1. Find the resistance of R1 and R2.
April 12, 2015

Maths help
The law connecting friction F and load L for an experiment is of the form F =aL+b, where a and b are constants. When F =5.6, L=8.0 and when F =4.4, L=2.0. Find the values of "a" and "b "and the value of F when L=6.5.
April 12, 2015

Maths help
A manufacture finds the total cost "C" for a product is expressed by C=3x2-8, and the total revenue "R" by R=3x-2, where x is the number of units sold. What is the breakeven point (where total cost=total revenue) to the nearest unit?
April 12, 2015

Maths help
Two flares are launched from a life raft. The height h of the first flare in metres above the sea is modelled by the formula h1= t2+t+1meters,and the second flare is h2=4-t where t is the time 12 in seconds after the flare is launched. Determine (i) Time taken and (ii) Height ...
April 12, 2015

Physics
1. A point on the edge of a large wheel of radius 0.45 meters moves through an angle of 170o at a constant angular velocity of 0.25 radians/sec. . (a) Find the length (in meters) of the arc described by the point. (b) Find the linear velocity (in m/sec) of a point located on ...
April 6, 2015

Biology
8) Describe the difference between a prosthetic group, cofactor, and coenzyme; provide an example of each.
March 24, 2015

Biology
What does b-mercaptoethanol do to secretory proteins?If you forgot to add b-mercaptoethanol to a secretory protein, would the protein's migration likely speed up or slow down? Why?
March 22, 2015

Biology
For each of the following characteristics, will the migration of the protein speed up, slow down, or remain unchanged if you do not add SDS? a)increase molecular weight of protein b) increase concentration of acrylamide c)decrease charge on protein d) increase surface area of ...
March 22, 2015

Biology
What does b-mercaptoethanol do to secretory proteins?If you forgot to add b-mercaptoethanol to a secretory protein, would the protein's migration likely speed up or slow down? Why?
March 22, 2015

Biology
What does b-mercaptoethanol do to secretory proteins?also...If you forgot to add b-mercaptoethanol to a secretory protein, would the protein's migration likely speed up or slow down? Why?
March 22, 2015

Biology
3) For each of the following characteristics, will the migration of the protein speed up, slow down, or remain unchanged if you do not add SDS? a)increase molecular weight of protein b) increase concentration of acrylamide c)decrease charge on protein d) increase surface area ...
March 22, 2015

Biology
What does b-mercaptoethanol do to secretory proteins?also...If you forgot to add b-mercaptoethanol to a secretory protein, would the protein's migration likely speed up or slow down? Why?
March 22, 2015

Biology
3) For each of the following characteristics, will the migration of the protein speed up, slow down, or remain unchanged if you do not add SDS? a)increase molecular weight of protein b) increase concentration of acrylamide c)decrease charge on protein d) increase surface area ...
March 22, 2015

Biology
also...If you forgot to add b-mercaptoethanol to a secretory protein, would the protein's migration likely speed up or slow down? Why?
March 20, 2015

Biology
What does b-mercaptoethanol do to secretory proteins?
March 20, 2015

Biology
3) For each of the following characteristics, will the migration of the protein speed up, slow down, or remain unchanged if you do not add SDS? a)increase molecular weight of protein b) increase concentration of acrylamide c)decrease charge on protein d) increase surface area ...
March 20, 2015

Algebra 2
Find a third-degree polynomial equation with rational coefficients that has roots -1 and i+1
March 13, 2015

Physics
The coefficient of static friction between the m = 3.75-kg crate and the 35.0° incline of the figure below is 0.320. What minimum force vector F must be applied to the crate perpendicular to the incline to prevent the crate from sliding down the incline?
March 10, 2015

Statistics
A history class is comprised of 5 female and 8 male students. If the instructor of the class randomly chooses 8 students from the class for an oral exam, what is the probability that 2 female students and 6 male students will be selected? Round your answer to decimal places.
March 10, 2015

Chemistry
The mass of spectrum of 2,4-dimethylpentane shows peaks at m/z 43, 57, and 85. Show the fragments which produce these peaks.
March 5, 2015

Chemistry
Consider the following reaction: CO(g)+H2O(g)⇌CO2(g)+H2(g) Kp=0.0611 at 2000 K A reaction mixture initially contains a CO partial pressure of 1348torr and a H2O partial pressure of 1780torr at 2000 K. Calculate the equilibrium partial pressure of CO2. Calculate the ...
February 25, 2015

Biology
describe how a population is thought to evolve through natural selection. Provide an example (specifically, the peppered moth)
February 20, 2015

Chemistry
name all the possible isomers of methyl nitrobenzoate and nitroacetanilide which can be formed
February 11, 2015

Organic Chem
Why does the carotene elute from the column before the chlorophylls?
February 11, 2015

Organic Chem
Why does the carotene elute from the column before the chlorophylls?
February 11, 2015

Organic Chemistry
Why does the carotene elute from the column before the chlorophylls?
February 11, 2015

Chemistry
Why does the carotene elute from the column before the chlorophylls?
February 11, 2015

Chemistry
Why does the carotene elute from the column before the chlorophylls?
February 11, 2015

Chemistry
Why does the carotene elute from the column before the chlorophylls?
February 11, 2015

Chemistry
A solution of 4-methyl-3-penten-2-one in ethanol shows an absorbance of 0.52 at 236 nm in a cell with a 1-cm light path. Its molar absorptivity in ethanol at that wavelength is 12,600 M^-1 cm^-1. What is the concentration of the compound?
February 11, 2015

Chemistry
A solution of 4-methyl-3-penten-2-one in ethanol shows an absorbance of 0.52 at 236 nm in a cell with a 1-cm light path. Its molar absorptivity in ethanol at that wavelength is 12,600 M^-1 cm^-1. What is the concentration of the compound?
February 11, 2015

Chemistry
Why does the carotene elute from the column before the chlorophylls?
February 11, 2015

Chemistry
Why should a mixture to be separated by column chromatography be introduced onto the column in a minimum amount of solvent?
February 11, 2015

Chemistry
Arrange the following compounds in order of decreasing ease of elution from a column of silica gel: a) 2-octanol; b) 1,3-dichlorobenzene; c) tert-butylcyclohexane; d) benzoic acid
February 5, 2015

Chemistry
name* Thanks for help DR. Bob
February 4, 2015

Chemistry
Okay i'll keep my answers the same. What do you think is the answer. Tert-butylcyclohexane > 1,3-dichlorobenzene > 2-octanol > benzoic acid
February 4, 2015

Chemistry
What precautions must be taken when you introduce a mixture of compounds to be separated onto a liquid chromatography adsorbent column?
February 4, 2015

Chemistry
oh no man. i just want different answers to see if the answers are right. And if people agree. I just don't want to take chances. Do you have a background in chemistry or something? I have no background in chemistry so i don't know if i'm seeing a right answer or ...
February 4, 2015

Chemistry
Once the adsorbent is packed in a liquid chromatography column, it is important that the level of the elution solvent not drop below the top of the adsorbent. Why?
February 4, 2015

Chemistry
What precautions must be taken when you introduce a mixture of compounds to be separated onto a liquid chromatography adsorbent column?
February 4, 2015

Chemistry
Once the adsorbent is packed in a liquid chromatography column, it is important that the level of the elution solvent not drop below the top of the adsorbent. Why?
February 4, 2015

physics
a metal object is suspended from a spring balance scale. the scale reads 800 N when it is suspended in air and 700 N when the object is completely submerged in water. find the buoyant force, the volume and the density of the metal.
February 3, 2015

world history
why is the ability to debate still important todat
February 2, 2015

chemistry
In 100 mL of distilled water,1.0g of thallium cholirde is added. How much of the 1.0g of TlCl doen't dissolve? The Ksp of TlCl is 3.6 x 10-6
February 2, 2015

chemistry
Please help !? Knowing that the concentration of Ag+ in a silver chromate solution is 1.5 x 10-3 M, calculate its solubility product at 25°C.
February 2, 2015

chemistry
Stuck on this one please help ! The solubility of barium sulphate, BaSO4, is 2.4 x 10-4 g/100 mL of solution. Calculate the Ksp of this solution.
February 2, 2015

chemistry
In 100 mL of distilled water,1.0g of thallium cholirde is added. How much of the 1.0g of TlCl doen't dissolve. The Ksp of TlCl is 3.6 x 10-6.
February 1, 2015

chemistry
Please help?! if 600 mL of a 0.04M KCl solution is mixed with 50mL of a 0.03M Na2SO4 solution, will a precipitate be formed? Explain your reasoning and/or show all calculations?
February 1, 2015

chemistry
I have no idea how to go about this question, please help! A clumsy chemist accidentally pours 100 mL of a 0.004 M Na2SO4 solution into a beaker containing 500 mL of 0.050 M CaCl2. Will a precipitate be formed? Explain your reasoning and/or show all calculations?
February 1, 2015

chemistry
Stuck on this questions ?! please help The solubility of barium sulphate, BaSO4, is 2.4 x 10-4 g/100 mL of solution. Calculate the Ksp of this solution.
February 1, 2015

physics
A ball is dropped from an upper floor, some unknown distance above your apartment. As you look out of your window, which is 1.5 m tall, you observe that it takes the ball 0.18 seconds to traverse the length of the window. Determine how high above the top of your window the ...
January 30, 2015

AP Chemistry
A sample of air contains 12.8 µg/m3 of beryllium dust. How many atoms of beryllium are present in a room with dimensions of 8 feet by 13 feet by 15.1 feet? Answer in units of atoms
January 20, 2015

Chemistry
You have a tank of helium with a volume of 10 liters that is currently under 40 atm of pressure. If you open the valve on the tank and release the helium into a room with a volume of 10,000 liters, how many atmospheres of pressure will the helium now be under? Second, what ...
December 18, 2014

math
A boat traveled 210 miles downstream and back. The trip downstream took 10 hours. The trip back took 70 hours. What is the speed of the boat in still water. What is the speed of the current?
December 15, 2014

Math
(13.98 + 3.96)=17.94/6=2.99
December 12, 2014

Chemistry, Vapor Pressure
Select the pair of substances in which the one with the higher vapor pressure at a given temperature is listed first. 1. C7H16, C5H12 2. CCl4, CBr4 3. H2O, H2S 4. CH3CH2OH, CH3-O-CH3 5. Xe, Kr
December 11, 2014

Analytical Chemistry
Calculate the ppm of the sodium ions when 2.91 g of sodium triphosphate are added to 2.33 L of solution. I earnestly have no idea how to solve this...
December 9, 2014

Math
) A car dealership advertises a 15% discount on all its new cars. In addition, the manufacturer offers a $1000 rebate on the purchase of a new car. Let x represent the sticker price of the car. a. Suppose only the 15% discount applies. Find a function f that models the ...
December 4, 2014

ratio proportions
The ratio of apples to oranges is 4:5. I have 200 apples and oranges total. How many are apples?
November 18, 2014

math
a basketball team needs 5 players. the team can choose from a group of 7 players. explain how to find the combinations of players that can be on the team.
November 18, 2014

chemistry
The vapor pressure of liquid chloroform, CHCl3, is 100. mm Hg at 283 K. A 0.198 g sample of liquid CHCl3 is placed in a closed, evacuated 400. mL container at a temperature of 283 K. Assuming that the temperature remains constant, will all of the liquid evaporate? What will ...
November 11, 2014

Math
A marine biologist is testing a new under water probe. The probe is catapulted from the ship into the air, descends under water to a predetermined depth, and then returns to the surface where it can be collected. The function that models the probe’s path is f(x) = 15t2...
October 30, 2014

Chemistry
what is the limiting reagent in these two reactions Reaction 1: CuSO4+2NaOH=Cuo+Na2SO4+H2O Reaction 2: CuSO4+NaCO3=CuCO3+Na2SO4
October 22, 2014

Calculus
An inverted conical tank is being filled with water, but it is discovered that it is also leaking water at the same time. The tank is 6 meters high and its diameter at the top is 4 meters. The water is being added to the tank at a constant rate. Some of this water is found to ...
October 19, 2014

Calculus
A bright light on the ground illuminates a wall 12 meters away. A man walks from the light straight toward the building at a speed of 2.3 m/s. The man is 2 meters tall. When the man is 4 meters from the building, how fast is the length of his shadow on the building decreasing?
October 19, 2014

Calculus
A pulley system on a pier is used to pull boats towards the pier for docking. Suppose that a boat is being docked and has a rope attaching the boat's bow on one end and feeding through the pier's pulley system on the other end. The pulley system is 1 meter higher than ...
October 19, 2014

Check my answer?
Conditional statement based on a Venn diagram 2 circles: large circle says quadrilaterals smaller inner circle says squares If a shape is a square then it is a quadrilateral.
September 29, 2014

physics
A ball is thrown straight upward. At 4.36 m above its launch point, the ball's speed is one-half its launch speed. What maximum height above its launch point does the ball attain?
September 21, 2014

Math
I don't know it
September 15, 2014

Math
Help please
September 15, 2014

Math
Find the distance between points (6, 16) and (–1, 14) to the nearest tenth
September 15, 2014

Math
Find the other endpoint given the first endpoint and the midpoint A = (3, 5) B = (5, -11) find C
September 15, 2014

Maths
A boy is flying a kite on a string 33m long. The string which is being held at 1.5m above the ground, makes an angle of 39* with the horizontal. How high is the kite above the ground (nearest cm)
September 14, 2014

Calculus
Suppose the area under the curve y=xe^(-mx) from 0 to 1 is 0.4. Find m.
September 8, 2014

Calculus
I am trying to find the total area under the curve, not just the integral...
September 7, 2014

Calculus
Suppose the total area under the curve y=x^2-mx+1 from 0 to 5 is 11.3024. Find m. I know that this means that i need to find the integral of the absolute value of x^2-mx+1 from 0 to 5 and set it equal to 11.3024, but I am not sure where to go from there.
September 7, 2014

math
56.67 is correct?
September 3, 2014

math
Find each unit rate. Round to the nearest hundredth if necessary. 357 miles in 6.3 hours
September 3, 2014

math
Find each unit rate. Round to the nearest hundredth if necessary. 5 pounds for $ 2.49
September 2, 2014

math
What is the slope of the budget line from trading with Friday (coconuts for fish)?
August 24, 2014

calculus 2
use the simpsons rule with n=10, arc length y=^3sqaure root x, for 1<=x<6
July 29, 2014

calc 2
find the maclaurin series for: f(x) = (1-3x)^-5. What is the radius of convergence?
July 27, 2014

Physics (HEELPPP)
A coin with a diameter of 1.90 cm is dropped on edge onto a horizontal surface. The coin starts out with an initial angular speed of 14.4 rad/s and rolls in a straight line without slipping. If the rotation slows with an angular acceleration of magnitude 1.88 rad/s2, how far ...
June 27, 2014

chemistry
At a certain temperature, Keq is 4.13 x 10^-5 for the equilibrium: 2IBr(g) ↔ I2(g) + Br2(g) Assume that the equilibrium is established at the above temperature by adding only the reactant to the reaction flask. What are the concentrations of I2 and Br2 in equilibrium ...
June 5, 2014

Global history
Compare and contrast European colonization of the Americas in the 16th and 17th centuries with European colonization of Africa and Asia in the 18th and 19th centuries. Be sure to address the motives for colonization and the impact that colonization had on native peoples. (Just...
May 28, 2014

Math
I think your answer looks fine. We are doing this in my school as well. The question is rather open for personal opinion, so as long as you can back it up, it is fine. Sorry if this does not help
May 28, 2014

Physics
an electron is sitting 10cm away from a small object -5nc it is let go and moves away from the charged object when it reaches a distance of 15 cm away find its speed
May 26, 2014

geometry
if a cone is 7.5 cm high and has a vertical angle of 70 degree calculate the diameter of its base.
May 16, 2014

Logic
Even if you know only some of them please help! 1. Give a proof of the following: (∀F)( (P)( [ιxGx][Px] ⊃ F(P) ) ⊃ F(G)) (∃F)( (P)( F(P) ≡ [ιxGx][Px]) Therefore, E!(ιxGx) 2. Prove the following: [ιxMx][Thales believed that Bx...
May 14, 2014

Trigonometry
Two radar stations are 50 miles apart. Both are tracking the same plane. At this moment, the angle between station 1 and the plane is 73 degrees and the angle between station 2 and the plane is 46 degrees. How far is the plane from station 2?
May 6, 2014

physics
Sunlight strikes the surface of a lake at an angle of incidence of 44.5°. At what angle with respect to the normal would a fish see the Sun?
May 4, 2014

physics
How would a diamond look if there were no dispersion?
May 4, 2014

physics
Question Part Points Submissions Used 1 2 3 4 0/0.37 0/0.37 –/0.37 –/0.37 4/15 1/15 0/15 0/15 Total 0/1.48 ...A diamond in air is illuminated with white light. On one particular facet, the angle of incidence is 46.05°. Inside the diamond, red light (ë = 660...
May 4, 2014

physics
A diamond in air is illuminated with white light. On one particular facet, the angle of incidence is 46.05°. Inside the diamond, red light (ë = 660.00 nm in vacuum) is refracted at 17.38° with respect to the normal; blue light (ë = 470.00 nm in vacuum) is ...
May 4, 2014

physics
Sunlight strikes the surface of a lake at an angle of incidence of 44.5°. At what angle with respect to the normal would a fish see the Sun?
May 4, 2014

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