Sunday
December 21, 2014

Posts by john


Total # Posts: 6,393

Chemistry help
The Lab experiment we did today was to analyze an antacid tablets to determine the actual content of NaHCO3. Suppose I dropped the tablets into the beaker and some of the reaction mixture splashed out. Would my final calculated mass of sodium bicarbonate in the tablet be ...
February 20, 2013

physics
An airplane is flying at a constant velocity parallel to the horizontal, and the pilot drops a flare. Assuming that the plane does not change course, where will the plane be relative to the flare when the flare hits the ground?
February 20, 2013

Biology
Please Help Quick,Write The Balanced Chemical Equation For Respiration In An Athlete In A Race.
February 20, 2013

Biology
Please Help Quick,Write The Balanced Chemical Equation For Respiration In Plants.
February 20, 2013

Biology
Please Help Quick,Under Anaerobic Condition,Explain What Happens To Glucose In Yeast And In Humans?
February 20, 2013

Physics
Rapids in rivers occur when the river narrows. Consider a simple river where the cross-section can be modeled as a rectangle 60 m wide and 2 m deep. If the speed of the river water at this point is 1 m/s, what would be the speed of the water in m/s at a point further down ...
February 20, 2013

Please Help Me
Use the equation for the synthesis of hydrogen to answer the following. C (s) + H2O (l) -> CO (g) + H2 (g) deltaH = + 31.3 kcal/mol carbon deltaS = +32 cal/(mol•K) Calculate the energy change (deltaH) when 5.00 g of carbon is consumed. Calculate the energy change (...
February 19, 2013

math
In third grade... Write an equation comparing test scores of 88 and 97. (Use a box for missing number) do you know how to answer this?
February 19, 2013

math
In third grade... Write an equation comparing test scores of 88 and 97. (Use a box for missing number) do you know how to answer this?
February 19, 2013

Chemistry
Use the equation for the synthesis of hydrogen to answer the following. 10 points. C (s) + H2O (l) -> CO (g) + H2 (g) deltaH = + 31.3 kcal/mol carbon deltaS = +32 cal/(mol•K) Calculate the energy change (deltaH) when 5.00 g of carbon is consumed. Calculate the energy ...
February 19, 2013

chemistry
assume the true concentration of the acetic acid solution is .175M and calculate the percent relative error in your measurement?
February 19, 2013

Maths
R=square root of u squared plus v squared divided by m and u and v are positive.Find u when r=3,v=6 and m=5
February 19, 2013

Maths
R=square root of u squared plus v squared divided by m and u and v are positive.Find u when r=3,v=6 and m=5
February 19, 2013

Math
Find the sum of all primes a<1000, such that a^k +1 = b^{m+1} for some positive integers k,b,m.
February 19, 2013

Math
Let S(n) denote the sum of digits of the integer n. Over all positive integers, the minimum and maximum values of S(n)/S(5n) are X and Y, respectively. The value of X+Y can be written as a/b , where a and b are coprime positive integers. What is the value of a+b?
February 19, 2013

Math
John is building a fence that is 6 feet high and 18 feet wide to put around his garden. He has two sizes of boards that he can use. One is 2 feet by 6 feet and the other is 4 feet by 6 feet. John can put the boards either horizontally or vertically and he has lots of boards of...
February 19, 2013

Maths
Siuan's grandmother recently signed up for a twitter account. She only follows five people - her five grandchildren. Each day, each of her grandchildren make two tweets and at the end of the day Siuan's grandmother gets an e-mail that lists all ten tweets in ...
February 19, 2013

Math
Killer robots are trying to take over the world. They know the password to the doomsday weapon is 5 digits long and contains either 0 or 1, and either 2 or 3, and either 4 or 5, and either 6 or 7, and either 8 or 9. If the robots can enter 5 passwords per second, how long (in ...
February 19, 2013

math
"The area of a rectangle is 360m2. If its lengh if increased by 10m and its width is decreased by 6m, then its area does not change. Find the perimeter of the original rectangle." I need to use the "guess and test" or the "draw a diagram" method ...
February 18, 2013

Physics
The Royal Gorge bridge over the Arkansas River is 310.0 m above the river. A 59.0-kg bungee jumper has an elastic cord with an unstressed length of 62.0 m attached to her feet. Assume that, like an ideal spring, the cord is massless and provides a linear restoring force when ...
February 17, 2013

Chemistry
You use 2.80 g of NaHCO3, and determined that 2.83 g of carbon dioxide ar produced. Convert the mass of NaHCO3 to moles: Convert the mass of CO2 to moles:
February 16, 2013

Chemistry
Some of your reaction mixture splashed out of the beaker when you dropped the tablets into the acetic acid. How would this affect your measurements? Woud your final calculated mass of sodium bicarbonate in the tablet be artificially high or low as a result of this splashing?
February 16, 2013

dilution please help
How to use serial dilution to dilute a stock solution at 15000 fold dilution?
February 16, 2013

Dilution
Please, if possible, check if my method of dilution is correct Problem: Given a very concentrated liquid PBS, dilute it to 1:15,000 My approach is to use serial dilution First: dilute it 15x (50ul of PBS + 750ul of water)... this will give 1:15 Second: dilute 10xfold more (...
February 15, 2013

jones
I have a unscramble analogies worksheet that I can't answer. Here are the analogies: ________:judical branch [eempusr ructo] radius:______[meeairtd] brass instruments:_____[stoaercrh] _______:poem[anzsat] _______:pants[bowaerrd] thank yo
February 14, 2013

Chemistry
A solvent has a molar mass of 37.2 g/mol and a normal boiling point of 111.2 oC. The boiling point elevation constant, K b , for this solvent is 1.58 oC/m. If 18.7 g of a nonelectrolyte having a molar mass of 20.5 g/mol are mixed with 170.0 g of the solvent, what is the ...
February 14, 2013

College
A bod of 10kg is traveling in straight line at 10m/s (a)what is de momentum?(b)what is de average force required to increase its velocity 4rom zero to 20m/s in 4seconds?
February 13, 2013

Physics
During an action potential, Na^+ ions move into the cell at a rate of about 3x10^-7 mol/m^2*s. How much power must be produced by the "active Na^+ pumping" system to produce this flow against a +30-mV potential difference? Assume that the axon is 40cm long and 30um ...
February 12, 2013

Pre cal
From a point A is 8.20 meters above level ground,the angle of elevation of the top of a building is 31degrees 20 min and the angle of depression of the base of the building is 12degree 50 min. Approximate the heighth of the building
February 11, 2013

Chemistry
Naphthalene combustion can be used to calibrate the heat capacity of a bomb calorimeter. The heat of combustion of naphthalene is -40.1 kJ/g. When 0.8210 g of naphthalene was burned in a calorimeter containing 1,000. g of water, a temperature rise of 4.21ÂÂ&...
February 11, 2013

Math
two sides of a triangle have the ratio of 3:4. The hypotenuse is 20. What are the measures of the two other sides?
February 11, 2013

Physics
A dropping ball initial at rest is dropped 1.5m; calculate a) the traveling time of the ball and b) its velocity just before reaching the ground.
February 10, 2013

probability
John has 3 unique coins such that the probability of obtaining a head when the coin is flipped is 1/10, 2/10 and 3/10, respectively. If he flips each of the 3 coins once, the probability that at least 1 heads appears is p. What is the value of 1000p?
February 10, 2013

probability
John has 3 unique coins such that the probability of obtaining a head when the coin is flipped is 110, 210 and 310, respectively. If he flips each of the 3 coins once, the probability that at least 1 heads appears is p. What is the value of 1000p?
February 10, 2013

Physics please help
During an action potential, Na^+ ions move into the cell at a rate of about 3x10^-7 mol/m^2*s. How much power must be produced by the "active Na^+ pumping" system to produce this flow against a +30-mV potential difference? Assume that the axon is 40cm long and 30um ...
February 10, 2013

Physics please help
Can you please help out am still stuck one this
February 10, 2013

Physics please help
During an action potential, Na^+ ions move into the cell at a rate of about 3x10^-7 mol/m^2*s. How much power must be produced by the "active Na^+ pumping" system to produce this flow against a +30-mV potential difference? Assume that the axon is 40cm long and 30um ...
February 10, 2013

physics
8. Electric field lines arising from two small charged particles P and Q. Consider the following two statements: i.The charge on P is smaller than the charge on Q. ii.The electrostatic force on P is smaller than that on Q. Which of the above statements are true? A) Only i. B) ...
February 9, 2013

Pre-calculus
a) A particular ball always rebounds 3/5 the distance it falls. If the ball is dropped from a height of 5 meters, how far will it travel before coming to a stop? Explain the reasoning. b) Prove that if a1, a2, a3, ... is a geometric sequence,then ln(a1), ln(a2), ln(a3)... is ...
February 9, 2013

Chemistry
A student mixes 85.1 g of water at 69.6°C with 58.1 g of water at 22.0°C in an insulated flask. What is the final temperature of the combined water?
February 9, 2013

Algebra
suppose you invest $1100 at an annual interest rate of 4.3% compounded continuously. How much will you have in the account after 15 years?
February 8, 2013

Limit
(x2-27)/(x-3) as x tends to 3
February 6, 2013

Statistics
A telephone company's records indicate that private customers pay on average $17.10 per month for long-distance telephone calls. A random sample of 10 customers' bills during a given month produced a sample mean of $22.10 expended for long-distance calls and a sample ...
February 5, 2013

Statistics
Which of the following conditions doesn't need to be met before you can use a two-sample procedure? The responses in each group are independent of each other. Each group is considered to be a sample from a distinct population. The same variable is measured in both samples...
February 5, 2013

chemistry help !!!!!!!!!!!!!!!!
complete the following paragraph relating to the enzyme,b -galactosidase .this enzyme hydrolyses the disaccharide lactose to constituent monosaccharides ,galactose and glucose ,drag and drop the approprite words into the correct space. the enzyme ,B-galactosidase is added to a...
February 2, 2013

chemistry help !!!!!!!!!!!!!!!!
complete the following paragraph relating to the enzyme,b -galactosidase .this enzyme hydrolyses the disaccharide lactose to constituent monosaccharides ,galactose and glucose ,drag and drop the approprite words into the correct space. the enzyme ,B-galactosidase is added to a...
February 2, 2013

calculus 1
y-28=(18x-3x2)(x-2)
January 31, 2013

Math!!!
I have a input output table and I can't figure out the rule here is the chart X. Y _______________ 1. | 3 4. | 7 7. | 11 Can u figure it out I'm having a really hard time with this problem!!!!
January 30, 2013

Physics / Heat Transfer
How much heat must be removed from a 200 g block of copper to lower its temperature from 302 oF to 68 oF? Specific heat of copper: c = 0.092 kcal/(kg K) a. 2.4 kcal b. 2400 kcal c. 18.4 kcal d. 12 kcal e. 26 kcal
January 30, 2013

MATH
4[23 - (6 + 4)]
January 29, 2013

MATH
4[23 - (6 + 4)]
January 29, 2013

ACT/SAT MAP PREP
- t^5 u^5 v^5/ tuv =????????
January 29, 2013

math
write the number in words 84,508
January 29, 2013

computer science
Write a method printBackwards that prints an array of integers in reverse order, in the following format. For the array {1, -3, 4, 7, 2}: element [4] is 2 element [3] is 7 element [2] is 4 element [1] is -3 element [0] is 1
January 29, 2013

5th grade math
Using input output tables input 3 4 5 6 0 10. Output 9 16 25 36 0 100 what is the input output rule?
January 29, 2013

math
thank you
January 27, 2013

math
The sum of four consecutive multiples of 5 is 230. What is the greatest of these numbers ?
January 27, 2013

math
1. If 2x/5y=6,what is the value of y, in terms of x ? 2. 11/4-a=3 , What is the value of a in the equation ?
January 27, 2013

Math
Thank u :)
January 25, 2013

Math
Working with linear equations: 3(2x+1) - 4 (x+2) = 9
January 25, 2013

math help
15
January 25, 2013

nursing
For example: Kim, a neonatal ICU nurse, has cared for baby Sara for the past month. Baby Sara is about to be discharged today in good health. The baby’s parents want to give Kim a personal gift as an expression of their appreciation and have also invited Kim to the baby&#...
January 24, 2013

math
thank you , Ms.Sue
January 23, 2013

math
3. x + 11 4. H x 15
January 23, 2013

math
thank you
January 23, 2013

math
1. two times the number of windows 2. 81 increased by n 3.eleven more than a number 4. $15 times the number of hours
January 23, 2013

math
Write a variable expression for each word phrase. 1. two times the number of windows 2. 81 increased by n 3.eleven more than a number $15 times the number of hours
January 23, 2013

Math
A woman invested $15,000, part at 7% annual interest and the rest at 8%. If she earned $1,100 in income over a one-year period, how much did she invest at 7%?
January 23, 2013

Physics
Two particles are fixed along a straight line, separated by a distance 6.0 cm. The left one has a charge +2.0 nC and the right one has a charge of +6.0 nC. You must try to locate a point where the electric field is zero. (a) What is the location of the point? (b) How far from ...
January 21, 2013

chemistry help !!!!!!!!!!!!!!!!
Benzoic acid react with NH2 group Draw the product of this reaction, name the new functional group produced, state the type of reaction that has occurred, name any other products of the reaction and briefly explain how you arrived at your answer.( one or two sentences.)
January 21, 2013

Physics
True or false?equal masses of two different gases placed in containers of equal volume at equal temperature must exert equal pressures
January 21, 2013

chemistry help !!!!!!!!!!!!!!!!
Identify 4 functional group: HO-HO-BENZENE RING-CH2-CH-NH2-C=O-OH 1)carboxylic acid functional group 2)amine functional group 3)alcohol functional group i only know three is anyone can tell me the last functional group.please
January 21, 2013

chemistry help !!!!!!!!!!!!!!!!
Identify 4 functional group: O || HO CH2 C \ / \ / \ Benzen ring CH OH / | HO NH2 1)carboxylic acid functional group 2)amine functional group 3)alcohol functional group i only know three is anyone can tell me the last functional group.please
January 21, 2013

Chemistry
What mass of glucose can be produced from a photosynthesis reaction that occurs using 21.2 mol CO2? Answer in units of g
January 20, 2013

Pol 201 American National Goverment
9. The Connecticut Plan was called the Great Compromise because (Points : 1) it allowed states with larger populations to have more representatives in the House and each state to have the same number of votes in the Senate. it allowed slave states to keep their slaves. it ...
January 20, 2013

Chemistry/Calculus
Thank you, sir. However, I stillmust be doing something wrong because I am not getting the answer. My calculator will give me an error if I do it that way. On my TI-30 I punch in 2nd button, the hit Ln, then (1.00 X 10-2 / 1.65 X 10-2) and get 1.83...
January 19, 2013

Chemistry/Calculus
I have a question about how to plug in numbers on my calculator (TI-30XIIS) to get an answer. How would I put in my calculator... ln 1.00X 10-2 mol/L /1.65 X 10-2 mol/L to get-0.501? I keep getting the wrong answer...
January 19, 2013

math
1. solve for y: 2y-3<9+y 2. solve for x: 7-2x>3y
January 19, 2013

English
How did the elephant save the life oe porus.
January 19, 2013

thermal physic
What is the average translational kinetic energy of one mole Of gas molecule in an ideal gas at 37degree celsius
January 19, 2013

Chemistry
55.34g/mol^3
January 17, 2013

Chemistry
An element crystallizes in a body-centered cubic lattice. The edge of the unit cell is 2.77 , and the density of the crystal is 8.65 . Find the atomic weight of the element.
January 17, 2013

economics
How does a budget differ when you have an irregular income vs. a predictable income? irregular income is monthly budget.
January 16, 2013

economics
Jesse and Kimberly recently graduated from college and are starting a family. Currently, they are just making ends meet with their $45,000 salary. They want to contribute the maximum amount (currently $2,000) to fully fund an Educational Savings Account when their baby is born...
January 16, 2013

economics
thanks...
January 16, 2013

economics
Kimberly works for a well known financial company as a sales representative. She earns a small base salary but receives commission off every product she sells. Kimberly has basic living expenses in addition to a student loan. She wants to start adding to her Roth IRA and buy a...
January 16, 2013

Chemistry
At room temperature, ethanol's density is 0.789 g/mL while water's density is 0.997 g/mL. When a few milliliters of ethanol are added to water, the two liquids mix. A student is given a unknown liquid at room temperature and experimentally determines its density to be ...
January 16, 2013

physics
the magnitude of the tongue produced by a 3.0n force applied to a door at a perpendicular distance of 0.25 m from the hinge
January 15, 2013

Geometry
let x = witdth 4x+2 = length perimeter of rectangle = 2L + 2W substitute: 34 = 2(4x+2) +2x 34 = 8x + 4 + 2x 34-4 = 10x 10x = 30 x = 3 - width length = 4(3) + 2 = 12 + 2 = 14 :)
January 15, 2013

math
error.. that's supposed to be -10x = -1-6 -10x = -7 x = 7/10 im so sorry..
January 15, 2013

math
y = 2-4x Substituting, 3(2-4x) + 2x = -1 6-12x + 2x = -1 -10x = -1-5 -10x = -6 x = 6/10 or 3/5
January 15, 2013

PLEASE HELP ME IN THIS PHYSICS PROBLEM
A heat transfer of 9.5 x 10^5 J is required to convert a block of ice at -15°C to water at 15°C. What is the mass of the block of ice?
January 14, 2013

chemistry
how methane is produced or where it comes from?
January 14, 2013

math
If one side of a triangle is of length x and another side is of length x+6,which of the following could not be the lenght of the third side? a.5 b.7 c.9 d.11 e.13
January 13, 2013

math
The lengths of two sides of a parallelogram are 3 are 5. which of the following is a possible value for the length of a diagonal of the parallelogram? a.2 b.2 c.8 d.10 e.15
January 13, 2013

math
thank you, Reiny
January 13, 2013

pre algebra
hi i need some help
January 13, 2013

Discreete math problem
Determine the quotient q and remainder r for each of the following. where a is the dividend and b is the divisor. a=23, b=7
January 11, 2013

chemistry
1211
January 11, 2013

physics
A 2kg and a 4kg hang freely at opposite ends of a light inextensible string which passes over a small and light pulley fixed to a rigid support calculate the acceleration of the system
January 11, 2013

Pages: <<Prev | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | Next>>

Search
Members