Saturday

February 13, 2016
Total # Posts: 1,827

**chemistry**

I need help in the formula to calculate these types of problems 125ml of 0.43M of HCl + 17ml of 1.8M HCl Calculate the concentrations of solutions resulting from the mixture
*February 5, 2016*

**Chemistry**

A Se-75 source is producing 310 rem at a distance of 3.0 m. What is the distance needed to decrease the intensity of exposure to below 25 rem, the level at which no effects would be detectable.
*February 1, 2016*

**algebra**

what is the value of j in the equation square root of j plus the square root of j plus equals 3 the square root of j plus 10?
*January 24, 2016*

**Chemistry 105**

How do I write 23 grams+ 0.022 grams into a significant figure?
*January 20, 2016*

**Math**

Would it be true if you doubled it?
*January 10, 2016*

**Math**

A recipe calls for 3/4 cup flour and 2/3 cup butter. Does the recipe require more flour or butter? Is this still true if the recipe is doubled? Explain how you determined your answer.
*January 10, 2016*

**Math**

Tom has green and red tomatoes in a bag a 4 to 3 ratio 5 green tomatoes and 5 red tomatoes were removed making the ratio become 3 to 2 how many red tomatoes were originally in the bag Please show me how to work the problem
*January 5, 2016*

**math**

write a problem about going to the laundromat that has a hidden question. a single load of laundry costs $2 and a double load costs $4.explain how you solved your problem.
*December 16, 2015*

**Language arts**

OHHH MY LORD which one of yall is right
*December 1, 2015*

**Chem 1211**

Calculate the wavelength (in nm) of a photon needed to eject an electron with a kinetic energy of 3.93 eV from a metal surface with a work function of Φ = 0.60 eV. {h = 4.136×10-15 ev·s, c = 2.998×1017 nm/s}
*November 29, 2015*

**science - matter**

at what temperature will 45g of solid dissolve
*November 23, 2015*

**math**

Their are 12 crayons - 1 =9
*November 19, 2015*

**Language Arts**

What is the main theme of the story the bachelor tells in "The Story-Teller"? Good children win many medals Parks are beautiful places Too much goodness can be bad *** Good people do something bad eventually
*November 18, 2015*

**Language Arts**

In "The Story-Teller," what can you infer about the bachelor from the answers he gives when the children interrupt his story with questions? He is impatient He does not understand what others say He does not know what children like He has a good imagination ***
*November 18, 2015*

**Math**

A pole that is 3.2m tall casts a shadow that is 1.4m long. At the same time, a nearby tower casts a shadow that is 39.5m long. How tall is the tower? Round your answer to the nearest meter.
*November 14, 2015*

**Health**

My answer is Reproductive Gland
*November 13, 2015*

**Health**

When you wake up and a large pimple greets you when you look into the mirror, this endocrine gland is to blame Thymus Gland Reproductive Gland Thyroid Gland Pancreas
*November 13, 2015*

**Health**

During puberty, you may find yourself on a roller coaster, one minute you feel like crying and the next minute you are on top of the world. This could signify that you’re suffering from a hormonal imbalance. *** hormonal surge. hormonal shortage. hormonal discrepancy
*November 13, 2015*

**Calculus**

Squares with sides of length x are cut out of each corner of a rectangular piece of cardboard measuring 3 ft by 4 ft. The resulting piece of cardboard is then folded into a box without a lid. Find the volume of the largest box that can be formed in this way. b) Suppose that in...
*November 5, 2015*

**Physics**

A mass m = 85 kg slides on a frictionless track that has a drop, followed by a loop-the-loop with radius R = 19.2 m and finally a flat straight section at the same height as the center of the loop (19.2 m off the ground). Since the mass would not make it around the loop if ...
*October 31, 2015*

**BioChem**

Given stocks of 1M lactic Acid (pka 3.86) at pH 3.5, 2 M NaOH, 2M HCl and water; how would you prepare 4 Liters of 0.05M lactic acid at pH 3.25. I know you use the Hendersen-Hasselbeck eqn, just not sure how to start. Please help.
*October 29, 2015*

**Math**

Golds gym charges $150 to sign up and $10 per month. Fitness express charges not initial fee but charges $25 per month. When will the cost be the same? Show work please!!
*October 27, 2015*

**ap chem**

if 3.2 kcal of heat is added to 1kg of ice at 0 celcius, how much ice is produced and how much ice is left?
*October 21, 2015*

**Intermediate Algebra for College**

Imagine that you are looking to rent a car that costs $15 a day, and you will be charged an additional 25 cents for every mile you drive it during the day. The following formula can be used to calculate the cost for driving the car for a day: C = 0.25m + 15 If you were to ...
*October 15, 2015*

**math**

Find the absolute maximum and the absolute minimum value, if any of: f(x)= (-1x^2/8)+4x+3 on the interval (0,9)
*October 12, 2015*

**Math**

Find the absolute maximum and the absolute minimum value, if any of: f(x)= -1x^2/8+4x+3 on the interval (0,9)
*October 12, 2015*

**Calculus**

The altitude attained by a model rocket t seconds into flight is given by the equation: -t^3+3t^2+20t-3 where t is greater than or equal to 0 seconds. find the maximum altitude attained by the rocket. first I found the derivative of the original equation and set it to 0. which...
*October 12, 2015*

**chemistry**

A ground state hydrogen atom absorbs a photon of light having a wavelength of 93.73 nm. It then gives off a photon having a wavelength of 1094 nm. What is the final state of the hydrogen atom?
*October 11, 2015*

**Stats**

About 10% of the population of a large country is math phobic. If two people are randomly selected what is the probability both are math phobic? And hat is the probability that at least one is math phobic? Any way to do this on stat crunch?
*October 11, 2015*

**Math**

Monica Collects quarters, dimes, nickels and pennies. This afternoon she took $ 1.00 from her collection. She counted the coins and found that she had twice as many nickels as dimes. What coins could Monica have?
*October 1, 2015*

**Social Studies**

Idk jelp
*October 1, 2015*

**Social Studies **

Name three factors factors that combine to make the eastern usa a industrial region
*October 1, 2015*

**Math**

Survey the population or use a sample,you want to know the type of computer, if any, that each student in your class has at home?
*September 28, 2015*

**math**

35/65 in simplest form
*September 25, 2015*

**Physics **

If the rate of continental drift were to abruptly slow from 1.0 cm/y to 0.5 cm/y over the time interval of a year, what would be the average acceleration?
*September 15, 2015*

**math**

how can you find what each mark represents on a number line?
*September 13, 2015*

**fundamentals of math**

there are 40 bikes inspected. If 15 need new tires and 26 need gear repairs. -what is the greatest number of bikes that could have needed both repairs? -The least number that could have needed both? -Greatest number that could have needed neither repair?
*September 5, 2015*

**Art**

The society that a rises from a concern regarded as excellent in art .
*August 31, 2015*

**Physical Chemistry**

If 5.00 mL of 3% H2O2 is decomposed, how many mL of gas will be produced at 1.01 bar and 25C?
*August 31, 2015*

**Determining whether expired air contains carbon dioxide**

1.Formulate a hypothesis for this investigation 2.State the aim of this investigation 3. a)Independent variable b)Dependent variable c)Controlled variable 4.State methods and the control
*August 23, 2015*

**physics**

A car travels at a constant speed of 30 mph for 20 miles, at a speed of 40 fps for the next 20 miles, and then travels the final 20 miles at 90 kph. what is the average speed of the entire trip?
*August 23, 2015*

**Math**

The supplement of an angle measures 11 times its complement. Then the measure of the angle is... A. 9 degrees B. 81 degrees C. 90 degrees D. 99 degrees E. 100 degrees
*August 3, 2015*

**Math**

Thanks
*August 3, 2015*

**Math**

jack and jerry can complete a job together in 4 hours. if jack require 6 hours to do the job alone, how many hours will it take jerry to do the job alone. A.12 B.10 C.8 D.6 E.4
*August 3, 2015*

**chemistry**

The formula for rust can be represented by Fe2O3. How many moles of Fe are present in 24.6 g of the compound? Please guide me through it thank you!
*July 28, 2015*

**AP Chemistry**

The formula for rust can be represented by Fe2O3. How many moles of Fe are present in 24.6 g of the compound?
*July 28, 2015*

**Math**

Thanks
*July 10, 2015*

**Math**

Ralph's age is currently 3 years more than twice joe's age. But 3 years ago, ralph was was 4 times as old as Joe was the . How old will joe be in 10 years?
*July 10, 2015*

**Organic Chemistry**

Dr. Bob, Thank you for the chart; its really helps. Just to make sure I am on the same page as you. I look up the bonds listed. F-I has the highest deltaHf (kj/mol). So that means that is takes more energy to break that bond; thus have the strong bond?
*June 22, 2015*

**Organic Chemistry**

1. Which of the following bonds is the strongest? a. F-F b. F-Cl c. F-Br d. F-I I think it's A because of the same atomic radius. Is that correct? Am I on the right track?
*June 22, 2015*

**geometry**

An artist wants to make alabaster pyramids using a block of alabaster with a volume of 576 cubic inches. She plans to make each pyramid with a square base area of 3 square inches and a height of 4 inches. At most, how many pyramids can the artist make from the block of ...
*June 19, 2015*

**Chemisrty**

Calculate the grams of substance from the moles of substance given.... 2 moles C6H10O5. Please help I am lost!
*June 17, 2015*

**Organic Chemistry**

Which isomer of 1-ethyl-3-methylcyclohexane is more stable, cis or trans? My teacher hasn't covered this material as of yet, but we have a test done tomorrow on it. What is a cis and trans? Not sure how to begin figuring this out. My text book isn't helpful. Thanks
*June 15, 2015*

**Organic Chemistry**

Thank you Dr.Bob. For some reason my textbook doesn't have any answers to the selected problems so I don't know if I on the right track. I really appreciate your help.
*June 14, 2015*

**Organic Chemistry**

What is the hybridization of all the atoms (other than hydrogen) in each of the following species? a) NH3 e) +NH4 i) H3O+ b) BH3 f) +CH3 j)H2C=O c) -CH3 g) HCN d)*CH3 h) C(CH3)4 There are a couple I don't know how to do. Please help? Did I do the other correctly? Thanks. a...
*June 14, 2015*

**Organic Chemistry**

Is eutectic point and eutectic mixture the same thing? If not what is the difference between the two? Thanks in advance.
*June 11, 2015*

**us gov**

what single word means the same thing as representative democracy
*June 10, 2015*

**Chemistry**

analyze and describe the different types of genetic mutations and their effects
*June 8, 2015*

**Math**

Q. Tim and Jorge hope they will be assigned to the same cabin at the summer camp. Each cabin has 8 beds in it. And Tim knows that he is saying in the green cabin not the red cabin. If there are 14 boys going to camp in addition to Tim and Jorge. What is the change that Tim and...
*May 28, 2015*

**Math**

Thanks!
*May 21, 2015*

**Math**

Thanks!
*May 21, 2015*

**Math**

Q. Neil found out that the Sunday paper that he delivers is about 1 pound and 12 ounces. He delivers 39 newspapers on Sunday's. How much do the 39 newspapers weigh? (Hint: 16 ounces = 1 pound) A. I tried adding 16 12 times but that didn't work after I found out it was ...
*May 21, 2015*

**Math**

4:31
*May 19, 2015*

**Math**

Q. Juan delivers papers every morning before he goes to school. He has to have all the papers delivered by 6:30 am. He has 86 papers and he figures it takes him an average of one and one half minutes to deliver each paper. At what time must he start in order to be done as ...
*May 19, 2015*

**Chemistry**

A 10.0mL sample of H2SO4 was neutralized by 13.5mL of 1.0M KOH. What was its molarity of H2SO4? What is the normality?
*May 18, 2015*

**Math**

Thank you
*May 14, 2015*

**Math**

292-223=69
*May 14, 2015*

**Math**

Q. Mrs.Ramirez's class was getting ready to plant tomatoes. They we're wondering if each package of tomato seeds contained the same number of seeds. They counted the seeds in four packages and found that there was a average of 73 seeds in the package. The first three ...
*May 14, 2015*

**Townview**

Elaine is painting a fence. She knows that she needs 1 gallon of paint for each 10 feet of fencing. The fencing will enclose a rectangular yard that is 3 yards long and 2 yards wide. How much paint does Elaine need? (Remember 3 feet = 1 yard)
*May 14, 2015*

**Chemisty**

Dr. Bob, Where are you getting the 0.693 from?
*May 14, 2015*

**Chemisty**

The activity of a radioisotope is 3000 counts per minute at one time and 2736 counts per minute 48 hours later. What is the half-life of the radioisotope?? a) 831hr b)521hr c)361 hr d)1.44hr
*May 14, 2015*

**Math**

Q. Mr. Kincaid's class wants to plant 1/4 (fraction) of its 12-foot-square plot with tomatoes. Of the remaining garden, 1/3 will be pears. Of the rest of the plot,1/2 will be radishes, and 1/2 will be lettuce. How many square feet of radishes will the class plant.?
*May 13, 2015*

**Bio 20**

Hydrogen sulfide gas is combusted with oxygen gas to produce sulfur dioxide gas and water vapour. If there is 19.3 L of oxygen gas, what maximum volume of hydrogen sulfide gas could be combusted?
*May 11, 2015*

**Chemistry 20 **

Hydrogen cyanide gas is produced industrially by the reaction 2 CH4(g) + 3 O2(g) + 2 NH3(g) → 2 HCN(g) + 6 H2O(g) What volume of O2(g) is needed to completely react 17 L of CH4(g) at STP?
*May 11, 2015*

**Chemisty**

What is the molar solubility of AgCl, Ksp= 1.60x^-10, in a solution that also contains 0.0250 M KCl? The answer is 1.60x^-10. But I am not sure why this is. Does it have to do with the solubility rules? Please Help.
*May 7, 2015*

**Medical science**

Dimethyl ether = predominate weak dipole-dipole intermolecular force. (positively charged hydrogen atoms and the negatively charged oxygen atoms). H+ H+ H+- C- O - C - H+ H+ H+ Ethanol = hydrogen bonding (Hydrogen bonding to oxygen) H+ H+ H+ - C - C - O - H+ H+ H+ Hydrogen ...
*April 29, 2015*

**Medical science**

Dimethyl ether = predominate weak dipole-dipole intermolecular force. (positively charged hydrogen atoms and the negatively charged oxygen atoms). Ethanol = hydrogen bonding (Hydrogen bonding to oxygen) Hydrogen bonds have higher boiling points
*April 29, 2015*

**chem**

a solution is prepared with 3.26g kcl and water to make 25.0ml,of kcl,what is the %(m/V) of the kcl solution.
*April 22, 2015*

**Molarity question**

ahh thank you!
*April 18, 2015*

**Molarity question**

okay so in lab we made up 2 solutions of FeCl3 and KI. We varied the volumes...I was just wondering how to calculate a new concentration for those solutions. We weighed out .825g of the FeCl3 and 1.35 g of the KI. For trial one we used 20 mL of both. For trial 2 we used 20.0 ...
*April 18, 2015*

**Chemistry: Potentiometric Anyalysis**

Ok. Thank you. That is what I was thinking. I really appreciate your help.
*April 14, 2015*

**Chemistry: Potentiometric Anyalysis**

I am still working on a handful of the calculations.
*April 14, 2015*

**Chemistry: Potentiometric Anyalysis**

DrBob222, In the lab we used a NaOH solution with a 0.1088M to calculate the equivalence point of a unknown weak acid using "Logger Pro" program. I used 0.4530g of the unknown acid and dissolved it in 75ml of distilled water. For my 3 three trials, I gather enough ...
*April 14, 2015*

**Chemistry: Potentiometric Anyalysis**

If the pH probe was miscalibrated and reports the pH to be 1 unit higher than the true pH of the solution it is in, would the molar mass you report for the solid acid be higher, lower, or equal to the true molar mass of the acid? This for my post lab write up. I think that the...
*April 14, 2015*

**Math**

Perform the calculations 6 ft, 5 in,-2 ft, 7 in = what in ft, and inches Thanks
*April 14, 2015*

**Math**

Perform the following calculations 7 yds , 1ft -3 yds, 2 ft= what in ft Thanks
*April 14, 2015*

**Math**

A plane has a height of 1000 m. You see the plane at an angle of 40 degrees with the ground . How far away is the plane from where you are standing.
*April 12, 2015*

**Math**

A wall has dimensions 25 m by 10 m represent the wall with a drawing if the scale is 1 cm represents 5 m
*April 12, 2015*

**Chemistry**

0.688g of antacid was treated with 50.00ml of 0.200M HCl. The excess acid required 4.21 mL of 1.200 M NaOH for back-titration. What is the neutralizing power of this antacid expressed as mmol of HCl per gram of antacid? I think the answer should be: (50.00ml HCl)(0.200M HCl)= ...
*April 6, 2015*

**physics**

A car speeds up uniformly from rest so that it has a velocity of 30ms -1 after 20 second.How far does the car travel in first 10 seconds?
*April 6, 2015*

**physics**

A car speeds up uniformly from rest so that it has velocity of 30 ms-1 after 20 seconds. Question/ How far does the car travel in first 10 seconds?
*April 6, 2015*

**physics**

A car speeds up uniformly from rest so that it has a velocity of 30 ms-1 after 20 second. How far does the car travel in first 10 second?
*April 6, 2015*

**Chemistry**

The bubble in the tip of the buret is not removed prior to performing the NaOH standardization. Will the reported concentration of the NaOH be greater than, less than, or equal to the true concentration of the NaOH if the bubble is flushed from the buret during the titration? ...
*April 4, 2015*

**Chemistry**

am I doing this equation correctly, please help. K3PO4(aq) + Ba(NO3)2(aq) my answer: 3K(NO3)2(aq) + 2Ba(PO4)3(s) Double displacement precipitation
*April 4, 2015*

**Chemistry**

Why can't milk of magnesia (Mg(OH)2), act as a buffer?
*April 2, 2015*

**Chemistry**

A jar contains 75mL of a .45M silver nitrate solution. Will 200g of solid copper be enough to bring all the silver out of solution as a solid?
*March 30, 2015*

**Chemistry**

Thank you Dr. Bob222
*March 30, 2015*

**Chemistry **

Given that Ka for HIO is 3.2 × 10-11 at 25 °C, what is the value of Kb for IO– at 25 °C? Then, Given that Kb for C6H5NH2 is 1.7 × 10-9 at 25 °C, what is the value of Ka for C6H5NH3 at 25 °C? I don't know where to start? Do I need an ICE ...
*March 30, 2015*

**Physical Science**

A man loads 1,000 sacks of flour into a truck in 30 minutes. each sack has a mass of 20 kg and the man must lift each sack 1.00 m from a cart up onto the truck bed. How much power did the man develop?
*March 30, 2015*

**Physics**

A motorist is trying to loosen a stubborn lugnut by standing on the end of a wrench. The wrench is inclined 33.8 degrees above the horizontal and the distance from the center of the nut to the end of the wrench is 0.60 m. Assuming the motorist does not bounce up and down on ...
*March 29, 2015*