Monday

June 27, 2016
Number of results: 30,486

**Algebra (please help!)**

Mary has a solution that is 60% alcohol and another that is 20% alcohol. How much of each should she use to make 100 milliliters of a solution that is 52% alcohol. I totally forget how to do this kind of problem. Please help if you can! Thank you so much! :)
*May 29, 2009 by Faith*

**ALGEBRA**

How do you know if a quadratic equation will have one, two, or no solutions? How do you find a quadratic equation if you are only given the solution? Is it possible to have different quadratic equations with the same solution?
*March 28, 2010 by GGIFT*

**Chemistry**

0.10 M solution of a weak monoprotic acid has a hydronium-ion concentration of 5.0 * 10^-4 M. What is the equilibrium constant, Ka, for this acid? a. 5.0 *10^-2 b. 5.0 * 10^-3 c. 2.5 * 10^-4 d. 2.5 * 10^-5 e. 2.5 * 10^-6 2. (Points: 1) What is the carbonate-ion, CO3^-2, ...
*May 13, 2010 by wite2khin*

**college Chemistry**

A 21.18 mL of 0.250 M NaOH is titrated with a H2SO4 solution. The initial volume of H2SO4 was 13.28 and the final volume of H2SO4 was 28.29 mL when the solution turned very slightly pink. What is the concentration of NaOH?
*December 6, 2010 by Ivy*

**Chemistry Help Pls!!!**

A 21.18 mL of 0.250 M NaOH is titrated with a H2SO4 solution. The initial volume of H2SO4 was 13.28 and the final volume of H2SO4 was 28.29 mL when the solution turned very slightly pink. What is the concentration of NaOH?
*December 6, 2010 by Jerome*

**college Chemistry**

A 21.18 mL of 0.250 M NaOH is titrated with a H2SO4 solution. The initial volume of H2SO4 was 13.28 and the final volume of H2SO4 was 28.29 mL when the solution turned very slightly pink. What is the concentration of NaOH?
*December 7, 2010 by Ivy*

**Precalculus **

Solve (log x)^2 = log x Also, when will their be a possibility that an equation will have an extraneous solution? Like if you got two solutions for a log equation, will a negative solution for x automatically be extraneous?
*November 20, 2012 by marcus *

**Chemistry**

A reference solution is to be prepared with 5 PPM parabenzopyrene (molecular weight = 252). The quantity of parabenzopyrene required for preparing one litre 5 PPM solution is (A) 252 mg (B) 25.2 mg (C) 5 mg (D) 252 g
*June 25, 2013 by rohit*

**Chemistry**

A 2.50 L flask was used to collect a 5.65 g sample of propane gas, C3H8. After the sample was collected, the gas pressure was found to be 741 mmHg. What was the temperature of the propane in the flask. P= 741 mmHg(1 atm/760 mmHg)= .975 atm V= 2.50 L n= 5.65 g C3H8 (1 mol/44 g...
*October 23, 2007 by Lauren*

**statistics**

The Sledge Tire and Rubber Company plans to warranty its new mountain bike tire for 12 months. However, before it does this, the company wants to be sure that the mean lifetime of the tires is at least 18 months under normal operations. It will put the warranty in place unless...
*March 12, 2012 by nouah*

**statistics**

A researcher wishes to estimate with 95% confidence the proportion of adults who have high speed internet access. Her estimate must be accurate within 4% of the true proportion. 1. Find the minimum sample size needed using a prior study that found that 48% of the respondents ...
*October 14, 2012 by Diana*

**Chemistry**

A solution of household bleach contains 5.25% sodium hypochlorite, NaOCl, by mass. Assuming that the density of bleach is the same as water, calculate the volume of household bleach that should be diluted with water to make 500.0 mL of a pH = 10.23 solution.
*March 23, 2012 by Jematormal91*

**chemistry**

A solution of household bleach contains 5.25% sodium hypochlorite, NaOCl, by mass. Assuming that the density of bleach is the same as water, calculate the volume of household bleach that should be diluted with water to make 500.0 mL of a pH = 10.23 solution.
*April 10, 2013 by sara*

**Chemistry**

A solution of household bleach contains 5.25% sodium hypochlorite, NaOCl, by mass. Assuming that the density of bleach is the same as water, calculate the volume of household bleach that should be diluted with water to make 500.0 mL of a pH = 10.10 solution.
*May 29, 2013 by JayJay*

**chemistry**

if i have a 21% solution of a product, and i need to make it a 9% solution of the same product what do i do? i am trying to dilute a product that is 21% to a 9% soultion so it can safety be used on cats. i know what to dilute it with, but i do not know how much or the math to ...
*January 19, 2016 by michele*

**Algebra**

Checking a few answers to some algebra problems: 1.Find the slope of the line that passes through the points (-4,1) and (3,5). I got m = 5-1 / 3-(4) Answer is m = 4/7 2.Find the equation, in slope-intercept form, of the line that passes through the points (-3, 3) and (-4, 2). ...
*October 15, 2007 by John*

**Physics**

You have a solution that contains Ca2+ ions and another that contains Na+ ions. How would adding a solution that contains CO2-3 ions enable you to tell which is which?
*March 15, 2015 by Channing*

**math**

Weights of the vegetables in a field are normally distributed. From a sample Carl Cornfield determines the mean weight of a box of vegetables to be 180 oz. with a standard deviation of 8 oz. He wonders what percent of the vegetable boxes he has grouped for sale will have a ...
*April 9, 2014 by Anonymous*

**Econ 112**

A researcher believes that the average size of farms in the U.S. has increased from the 2002 mean of 471 acres. She took a sample of 23 farms in 2011 to test her belief and found a sample mean of 498.8 acres and a sample standard deviation of 46.9 acres. At a 5% levelof ...
*June 18, 2013 by Help*

**chemistry**

Hydrocyanic acid (HCN) is a much weaker acid than nitrous acid (HNO2). The pH values of 0.1 M solutions of the potassium salts of these two acids were determined separately. The statement which describes these determinations most accurately is: a. ) Both solutions are acidic, ...
*November 2, 2008 by Anonymous*

**Chemistry II**

Acetone, C3H6O, is the main ingredient of nail polish remover. A solution is made up by adding 35.0mL of acetone(d=0.790g/mL) to 50.0mL of ethyl alcohol,C2H6O(d=0.798 g/mL). Assume that the volumes are additive. From this information calculate the molarity of acetone in the ...
*September 27, 2009 by Mandy*

**chemistry **

please check if I did this right ... calculate the mass of white solid CaCO3 that forms when 98ml of a 0.1M Ca(NO3)2 solution is mixed with 54 ml of a 2.5M Na2CO3 solution. Ca(NO3)2 + 2NaCO3 -> Ca(CO3)2 + 2NaNO3 .098*0.1 =.0090 .054*2.5 =.135 limiting reactant is Ca(NO3)2 ....
*January 29, 2010 by Krissy*

**chemistry**

A 0.15M solution of weak triprotic acid is adjusted (base added) so that the pH is 9.27(you can assume minimal volume change). The triprotic acid(H3A) has the following acid ionization constants: Kal=1.0*e-3, ka2=1*e-8,ka3=1*e-12. which species given below is present in the ...
*May 13, 2011 by vivanh*

**Statistics**

1. In developing patient appointment schedules, a medical center wants to estimate the mean time that a staff member spends with each patient. Using a value for the population standard deviation of eight minutes, determine: a. How large a sample should be taken if the desired ...
*October 27, 2008 by JYD*

**statistics**

Suppose that the percentage returns for a given year for all stocks listed on the New York Stock Exchange are approximately normally distributed with a mean of 12.4 percent and a standard deviation of 20.6 percent. Consider drawing a random sample of n= 5 stocks from the ...
*August 31, 2009 by Amy*

**Statistics**

Suppose that the percentage returns for a given year for all stocks listed on the New York Stock Exchange are approximately normally distributed with a mean of 12.4 percent and a standard deviation of 20.6 percent. Consider drawing a random sample of n= 5 stocks from the ...
*June 7, 2010 by Mary*

**QMB2100**

Chicken Delight claims that 90 percent of its orders are delivered within 10 minutes of the time the order is placed. A sample of 70 orders revealed that 60 were delivered within the promised time. At the .02 significance level, can we conclude that less than 90 percent of ...
*July 29, 2013 by Ariel*

**College Chemistry (DrBob222)**

You have 120.0 mL of a 0.245 M solution of NaCl in an open beaker. After several days, you test the solution and find that it now has a concentration of 0.348 M. How much water must have evaporated from the beaker given the new concentration?
*March 25, 2014 by Anonymous*

**chemistry**

A student weighs out 0.568 g of KHP (molar mass = 204 g/mol) and titrates to the equivalence point with 36.78 mL of a stock NaOH solution. What is the concentration of the stock NaOH solution? KHP is an acid with one acidic proton. a. 3.15 M b. 0.0757 M c. 0.943 M d. 0.100 M ...
*October 12, 2014 by mathew*

**AP CHEM**

I have multiple... 1) If a metal ore contains 23.1% pure metal, how many pounds of pure metal can be obtained from 38 pounds of metal ore? Answer in units of pounds. 2) For the reaction 3 F2 + Cl2 → 2 ClF3 , what is the maximum amount of ClF3 (92.4482 g/mol) which could ...
*October 13, 2015 by Shannon*

**statistics**

Customers arrive at a movie theater at the advertised movie time only to find that they have to sit through several previews and prepreview ads before the movie starts. Many complain that the time devoted to previews is too long (The Wall Street Journal, October 12, 2012). A ...
*November 16, 2014 by sean*

**Statistics**

28. A group of statistics students decided to conduct a survey at their university to find the average (mean) amount of time students spend studying per week. Based on a simple random sample, they surveyed 144 students. The statistics showed that students studied an average of...
*October 22, 2011 by Steph*

**math,correction**

can you check if how i solved it to show that my answer is no is correct. Is -4 a solution to the equation 7x-5+3x=6+x-10 This is what i did: 7(-4)-5+3(-4)=6+(-4)-10 -28-5-12=2-10 -45=-8 so the answer is no -4 is not the solution to the equation. Yes this is fine yes this is fine
*February 13, 2007 by jasmine20*

**Chemistry**

How would you prepare 150.0 mL of a 0.200 M aqueous solution of potassium chloride from a 0.500 M aqueous solution of potassium chloride?
*November 21, 2010 by Kiesha*

**chemistry**

is the following false the boiling point of a 0.5 aqueous solution of koh is higher than the boiling point of a 0.5m aqueous solution of kcl?
*December 2, 2010 by micki*

**chemistry**

if 10 ml of a 2M standard solution is used to neutralize 20mL of an unknown base what is the molarity of the unknown and is this standard solution an acid or base?
*June 7, 2011 by jessica*

**Chem 151**

A solution of ammonia and water contains 3.50×10^25 water molecules and 5.00×10^24 ammonia molecules. How many total hydrogen atoms are in this solution?
*September 13, 2011 by Tyler*

**chemistry**

A chemist wants to make 5.50 L of a 0.300 M lithium phosphate solution. What mass of lithium phosphate must be used to make this solution?
*November 3, 2014 by James*

**Chemistry**

What is the molarity of a solution that contains 2.17 moles of (SrCl2) in 2,660ml of solution? I know that the formula is molarity=moles/liters Liters=.2660
*June 21, 2015 by Ocean*

**statistics**

The average gasoline price of one of the major oil companies has been $3.20 per gallon. Because of cost reduction measures, it is believed that there has been a significant reduction in the average price. In order to test this belief, we randomly selected a sample of 36 of the...
*November 12, 2013 by Alex*

**Chemistry**

Redox Titrations I did a redox titration of NaBO3 with KMnO4. I used a .0545 M NaBO3 solution, and an average of .026 L of .01M KMnO4. I have to standardize the KMnO4 solution, does anyone know how to do this?
*March 25, 2009 by Ryan*

**Chemistry**

Trichloroacetic acid (CCl3CO2H) is a corrosive acid that is used to precipitate proteins. The pH of a 0.050 M solution of trichloroacetic acid is the same as the pH of a 0.040 M HClO4 solution. Calculate Ka for trichloroacetic acid.
*November 23, 2011 by Kaleen*

**mixture**

Sugar solution is composed of 40 grams of sugar and 200 grams of water. How many grams of sugar must be added to make a 60% sugar solution? (Kindly write the equation..... tnx)
*November 22, 2012 by HELP HELP MNHS*

**chemistry**

You have a solution that contains 340ml of water and 20ml of ethanol. Find the concentration of ethanol in this solution in each of the following units: (density of water is 1.00 g/ml, density of ethanol is 0.789g/ml)
*February 18, 2014 by Anonymous*

**chemisty problem help**

Carbon-12 contains 6 protons and 6 neutrons. The radius of the nucleus is approximately 70 pm. Calculate the volume of the nucleus and the volume of the atom. What percentage of the carbon atom's volume is occupied by the nucleus? Can someone tell me how to do this? Volume= 4/...
*February 8, 2007 by Tagen*

**chemistry**

Suppose 70.00 mL of a lithium hydroxide, LiOH, solution requires 55.42 mL of a 0.1050 M solution of propanoic acid, C2H5COOH, for neutralization. LiOH + C2H5COOH ® C2H5COOLi + H2O What is the concentration of the base solution? 0.08313 M 0.1663 M 0.3325 M 0.6650 M Question 2 4...
*October 9, 2010 by hope*

**Math ---HELP!!!!!**

sample of nine students is selected from among the students taking a particular exam. The nine students were asked how much time they had spent studying for the exam and the responses (in hours) were as follows: 18, 7, 10, 13, 12, 16, 5, 20, 21 Estimate the mean study time of...
*May 30, 2016 by angela*

**Probability and Statistics**

The proportion of adults living in a small town who are college graduates is estimated to be p = 0.6. To test this hypothesis, a random sample of 15 adults is selected. If the number of college graduates in the sample is anywhere from 6 to 12, we shall not reject the null ...
*November 29, 2013 by Katy*

**Probability and Statistics**

The proportion of adults living in a small town who are college graduates is estimated to be p = 0.6. To test this hypothesis, a random sample of 15 adults is selected. If the number of college graduates in the sample is anywhere from 6 to 12, we shall not reject the null ...
*November 30, 2013 by Katy*

**Probability and Statistics**

The proportion of adults living in a small town who are college graduates is estimated to be p = 0.6. To test this hypothesis, a random sample of 15 adults is selected. If the number of college graduates in the sample is anywhere from 6 to 12, we shall not reject the null ...
*November 30, 2013 by Katy*

**chemistry**

Two aqueous solutions of sucrose, C12H22O12, are mixed. One solution is 0.1495 M sucrose and has d = 1.018 g/mL; the other is 12.00 sucrose by mass and has d = 1.038 g/ml. Calculate the moles C12H22O12 percent in the mixed solution. Please provide steps
*February 17, 2010 by anonymous*

**chemistry**

Two aqueous solutions of sucrose, C12H22O12, are mixed. One solution is 0.1495 M sucrose and has d = 1.018 g/mL; the other is 12.00 sucrose by mass and has d = 1.038 g/ml. Calculate the moles C12H22O12 percent in the mixed solution. Please provide steps
*February 17, 2010 by anonymous*

**chemistry**

Two aqueous solutions of sucrose, C12H22O12, are mixed. One solution is 0.1495 M sucrose and has d = 1.018 g/mL; the other is 12.00 sucrose by mass and has d = 1.038 g/ml. Calculate the moles C12H22O12 percent in the mixed solution. Please provide steps
*February 17, 2010 by anonymous*

**science**

a student adds 3 spoons of salt to 100 ml of water. the solution is clear, with nothing on the bottom of the cup. one spoon of the slat ha a mass of 5g. what is the mass of the solution? after the water evaporates, what is the mass of the solid remaining in the cup?
*September 24, 2015 by linda*

**Chemistry **

In a titration of 35 mL of 0.40 M H3PO4 with 0.30 M KOH solution, what volume (in mL) of KOH solution is needed to reach the last equivalence point (i.e., point in the titration where enough KOH has been added to neutralize all three of the acidic protons in the phosphoric acid)?
*November 3, 2015 by Anonymous*

**1CHEM**

In a titration of 35 mL of 0.40 M H3PO4 with 0.30 M KOH solution, what volume (in mL) of KOH solution is needed to reach the last equivalence point (i.e., point in the titration where enough KOH has been added to neutralize all three of the acidic protons in the phosphoric acid)?
*November 3, 2015 by Anonymous*

**Chemistry **

In a titration of 35 mL of 0.40 M H3PO4 with 0.30 M KOH solution, what volume (in mL) of KOH solution is needed to reach the last equivalence point (i.e., point in the titration where enough KOH has been added to neutralize all three of the acidic protons in the phosphoric acid)?
*November 3, 2015 by Anonymous*

**chemistry**

Select only the True statements about buffer systems. Select all that are True. 1. Starting with NH3(aq) and adding a small amount of HCl(aq) will make a buffered solution. 2. The blood buffer, among other things, is supported by carbonic acid and its conjugate base ...
*March 28, 2014 by bekah*

**Thin Layer Chromotography**

Can you use TLC to distinguish various isomers from one another? In what kind of substance can you NOT distinguish the isomers from each other? i think it is not possible to distinguish If I have an unknown sample containing several ketones and want to use TLC to identify the ...
*November 5, 2006 by Sarah*

**chemistry**

a new compound composed of just Hex-Nuts and bolts is formed.A 13.7 Kg sample of the new compound is separated into its component elements with the following result 3.84 kg. of hex-nuts and 9.90 kg of bolts. 1. How many hex-nuts are present in the 13.7 kg sample 2. how many ...
*October 10, 2012 by Amanda*

**chem**

a new compound composed of just Hex-Nuts and bolts is formed.A 13.7 Kg sample of the new compound is separated into its component elements with the following result 3.84 kg. of hex-nuts and 9.90 kg of bolts. 1. How many hex-nuts are present in the 13.7 kg sample 2. how many ...
*October 22, 2012 by Amanda*

**Statistics**

The Deborah Heart Institute performs many open-heart surgery procedures. Recently research physicians at the Institute developed a new heart bypass procedure that they believe reduces the average length of recovery. The hospital board will not adopt the procedure unless there ...
*April 4, 2012 by Richard*

**chemistry**

In which of the following ways would you change the glass sample to make the ion exchange more efficient? a)Change the composition of the glass to increase the proportion of B2O3. b)Change the composition of the glass to add Na2O, Li2O, or MgO. c)Change the composition of the ...
*April 10, 2013 by Anonymous *

**Chemistry**

Write the chemical formula for the simplest heptane isomer and give its name, b) give the names of two heptane isomers with hexane as the base chain, c) give the names of names of the five heptane isomers with pentane as the base chain, d) give the name of the isomer with ...
*March 24, 2012 by Hannah*

**statistics 2**

In Hamilton County, Ohio the mean number of days needed to sell a home is 86 days (Cincinnati Multiple Listing Service, April, 2012). Data for the sale of 40 homes in a nearby county showed a sample mean of 80 days with a sample standard deviation of 20 days. Conduct a ...
*September 23, 2014 by ANAHI*

**statistics 2**

In Hamilton County, Ohio the mean number of days needed to sell a home is 86 days (Cincinnati Multiple Listing Service, April, 2012). Data for the sale of 40 homes in a nearby county showed a sample mean of 80 days with a sample standard deviation of 20 days. Conduct a ...
*September 23, 2014 by MIA*

**Statistics 2**

In Hamilton County, Ohio the mean number of days needed to sell a home is 86 days (Cincinnati Multiple Listing Service, April, 2012). Data for the sale of 40 homes in a nearby county showed a sample mean of 80 days with a sample standard deviation of 20 days. Conduct a ...
*September 24, 2014 by Vanessa*

**statistics 2**

In Hamilton County, Ohio the mean number of days needed to sell a home is 86 days (Cincinnati Multiple Listing Service, April, 2012). Data for the sale of 40 homes in a nearby county showed a sample mean of 80 days with a sample standard deviation of 20 days. Conduct a ...
*September 24, 2014 by Vanessa*

**Calculus**

I need to find the exact solution to: 2sin2x = sqrt(x)on the interval (0,pi) This is how I started it, but I don't think it's correct. sin2x = sqrt(x)/2 2sinxcosx = sqrt(x)/2 sinxcosx = sqrt(x)/4 What do I need to do now? need to find the exact solution to: 2sin2x = sqrt(x)on ...
*August 21, 2006 by Jen*

**Physical Science**

1. Which equation correctly shows beta decay? (A) 210/82 Pb -> 209/81 Tl + 0/-1 e + y (B) 210/82 Pb -> 209/83 Bi + 0/-1 e + y (C) 210/82 Pb -> 210/83 Tl + 0/-1 e + y (D) 210/82 Pb -> 210/83 Bi + y (E) 210/82 Pb -> 210/83 Bi + 0/-1 e + y 2. The half-life if radon...
*November 18, 2013 by CJ*

**ap statistics**

Which of the following is not correct? A. The rejection region is controlled by the alpha level and the alternate hypothesis. B. The p-value measures the probability that the null hypothesis is true. C. The probability of a Type I error is controlled by the selection of the ...
*April 24, 2014 by cassandra*

**Chemistry**

Please help me answer this question; The goal of the recrystallization procedure is to obtain purified material with a maximized recovery. For each of the following, explain why this goal would be adversely affected. a) In the solution step, an unnecessarily large volume of ...
*February 8, 2010 by Judy*

**chemistry**

An aqueous salt solution is formed by adding 11.67 g sodium sulfate (solute) to water (solvent). What mass (in g) of water is used if the freezing point of the solution is -12.9 oF. Kf H2O = 1.86 oC/m I know to use delta T= i*Kf*m I then solve for m. But, then I'm confused on ...
*February 26, 2012 by Alyssa*

**Inorganic Chemistry**

In a constant-pressure calorimeter, 70.0 mL of 0.340 M Ba(OH)2 was added to 70.0 mL of 0.680 M HCl. The reaction caused the temperature of the solution to rise from 22.00 °C to 26.63 °C. If the solution has the same density and specific heat as water (1.00 g/mL and 4.184 J/g·K...
*March 11, 2016 by Michael*

**Inorganic Chemistry**

In a constant-pressure calorimeter, 70.0 mL of 0.340 M Ba(OH)2 was added to 70.0 mL of 0.680 M HCl. The reaction caused the temperature of the solution to rise from 22.00 °C to 26.63 °C. If the solution has the same density and specific heat as water (1.00 g/mL and 4.184 J/g·K...
*March 11, 2016 by Michael*

**Chemistry**

When 0.5963g of a sample containing NaNO2 and some inert material is allowed to react with excess HSO3NH2, the volume of N2 gas produced is measured. The volume of N2 gas corrected to 298.15K and 100kPa is calculated to be 0.146L. Find the mass percent of NaNO2 in the sample ...
*May 25, 2011 by Mark*

**ChemB**

The activity of carbon 14 in living tissue is 15.3 disintegrations per minute per gram of carbon. The limit for reliable determination of age is based on carbon 14 is .10 disintegration per min per gram of carbon. Calculate the max age of a sample that can be dated accurately ...
*January 23, 2012 by L.Bianchessi*

**statistics**

A test of hypothesis is performed to determine whether the proportion of Montrealers (population 1) who want the decriminalization of marijuana is greater than the proportion of Torontonians (population 2) who want decriminalization of marijuana. A random sample of 115 ...
*March 27, 2015 by Anonymous*

**Business Statistics**

Customers arrive at a movie theater at the advertised movie time only to find that they have to sit through several previews and prepreview ads before the movie starts. Many complain that the time devoted to previews is too long (The Wall Street Journal, October 12, 2012). A ...
*October 22, 2014 by Noah*

**Algebra**

I'm not quite sure about these problems. I know how to do them, but it seems that I get the wrong answer. Maybe I'm supposed to get 'no solution' but I'm not sure. Could someone please help me with them? 5|6-5x|=15x-35 2|3x-7|=10x-8 1/4|4x+7|=8x+16 Ok for 5|6-5x|=15x-35 first ...
*September 14, 2006 by Maria*

**chemistry**

A 1.50 liter gas sample at 745mm HG and 25 celsius contains 3.55% radon by volume radon-220 is an alpha emitter with a half life of 55.6 seconds. how many alpha particles are emitted in 5 minutes by this sample? I got an answer 1.59x10^19 I started at 745/760=.980263 then ....
*June 17, 2012 by Nancy*

**physics**

A 100 g aluminum calorimeter contains 250 g of water. The two substances are in thermal equilibrium at 10°C. Two metallic blocks are placed in the water. One is a 50 g piece of copper at 79°C. The other sample has a mass of 83 g and is originally at a temperature of 100°C. The...
*April 28, 2010 by Kelsey*

**science (chemistry)**

I have to do this lab where I titrate Na2CO3 with HCl dilute solution but i had to add Methyl orange indicator to the solution and im not sure what the endpoint is supposed to be colored, is it supposed to be orange or pink?? im confused and just how orange is it supposed to ...
*June 21, 2007 by christina*

**Physical Science**

24. What happens when a solution of nitric acid (HNO3) is added to a solution of potassium hydroxide (KOH)? What are the products? 25. Which of the following compounds can react with H2SO4 to form a salt: NaCl, Ca(OH)2, HF, AlCl3, H2O, Mg(OH)2? Name the salt(s) that would form...
*October 15, 2013 by Alexandra*

**Chemistry**

A student began adding titrant to the acid solution, but stopped when she suddenly realized that she forgot to add the 3 drops of phenolphthalein. When she did, the solution immediately turned dark red! What can the student do to correct this error and salvage this trial, so ...
*October 27, 2013 by Matt*

**social studies**

A poll of 700 persons attending the Taste of Chicago showed that 455 persons, 65% of the sample, believed that the food was overpriced. It is estimated that 1,250,000 persons attend the Taste. Statistics suggest that, although 65% plus or minus 5% of attendees believe that the...
*April 10, 2015 by phia*

**chemistry**

how wold you prepare 2.00L of 1.00M HCl solution using 6.00 M HCl? i already found the volume of 6.00M HCl needed to be .333L. i am confused about how to actually prepare the solution. do i used a volumetric flask or any other glassware?
*February 26, 2011 by lindy*

**chemistry**

Calculate the percent ionization of a 0.15 formic acid solution in a solution containing 0.11 potassium formate. I have the formic acid Ka=1.8 *10^-4 When I solve for "x" I'm getting 1.1.44*10^-2 When I plug that into equation (x/0.15-x)*100, I'm getting 10.6% which is ...
*March 31, 2011 by redgy*

**calculus**

Solve the given equation. (Enter your answers as a comma-separated list. Let k be any integer. Round terms to three decimal places where appropriate. If there is no solution, enter NO SOLUTION.) sin θ cos θ − 2 sin θ = 0
*October 21, 2011 by stellar*

**Chemistry ammonia gas**

In an experiment i had a test tube with Ca(NO3)2 solution in it and I added NaOH and a piece of aluminium. After carefully heating the solution ammonia gas was formed Can you help me write the equation for the reaction? I don't know the other products just the ammonia gas ...
*October 29, 2008 by Marysia*

**Algebra**

A chemist has two solutions of sulfuric acid. The first is one half sulfuric acid and half water. The second is three-fourths sulfuric acid and one fourths water. He wishes to make 10 liters of a solution which is two-thirds sulfuric acid and one-thirds water. How many liters ...
*November 10, 2013 by Jane*

**STAT**

An independent-measures research study compares three treatment conditions with a sample of n = 10 in each condition. The sample means are M1 = 2, M2 = 3, and M3 = 7 a. Compute SS for the set of 3 treatment means. (Use the three means as a set of n = 3 scores and compute SS.) ...
*February 24, 2013 by Tracy*

**Math**

The owner of a large company is conducting a survey about job satisfaction, including questions about salary, hours, stress, and other conditions. There are about 800 employees in the company, including 100 executive positions, 650 middle-management positions, and 50 custodial...
*August 7, 2012 by Fatima*

**Chemistry**

Consider a solution containing 0.100M fluroide ions and 0.126M hydrogen fluroide. Calculate the concentration of fluoride ions after the addition of 5.00ml of 0.100M HCl to 25.0ml of this solution. a description as to how to get to the answer would be appreciated Use the ...
*March 29, 2007 by annonymous*

**math**

Describe two ways to determine whether or not a given point is a solution of a line. Which way is more accurate? Why? The only practical and fast way is to substitute the coordinates of the point into the equation. If the equation is "true", then it is a solution. Any other ...
*July 30, 2007 by heather*

**Chemistry**

Hi Can someone please help me undersand how to get the answer to this question A 15.0 mL solution of 0.050 mol/L AgNO3 was titrated with 0.0250 mol/L NaBr in the cell SCE || titrated solution | Ag(s) Find the cell voltage for 10.0 mL of titrant added. (a) -0.0312 V (b) 0.194 V...
*April 26, 2010 by James*

**Chem 112**

Calculate the pH of a buffer solution prepared by dissolving 0.12 mole of cyanic acid, HCNO and 0.65 mole of sodium cyanate, NaCNO in enough water to make 1.0 liter of solution. [Ka(HCNO) = 2.0 × 10-4] I know that this question has something to do with turning moles into ...
*March 21, 2011 by Bridget*

**Chemistry**

Acetic acid dissociates/ionizes itself as follows: CH3COOH(aq) ⇔ H+(aq) + CH3COO-(aq) If you add sodium acetate, CH3COONa, to the solution: a) a precipitate will be formed b) more acetic acid will be ionized c) the concentration of hydrogen ions will decrease d) the ...
*May 15, 2012 by Andrea*

**chemistry**

When 5.00 g of barium hydroxide are added to 250.0 mL of 0.250 hydrochloric acid in a calorimeter, the temperature off the solution increases from 25.0 C to 28.0 C. Calculate the enthalpy ( in kJ per mole of water) given the density of the hydrochloric acid is 1.01 g/mL and ...
*June 1, 2013 by Jen*

**Chemistry**

In a coffee cup calorimeter, 1.60 g of NH4NO3 is mixed with 75.0 g water at an initial temperature of 23.50 ºC. When the salt was completely dissolved, the solution temperature of the calorimeter became 21.80 ºC. Assume the solution’s specific heat capacity is 4.184 J/g. ºC. ...
*March 10, 2014 by Eddie*