Sunday

January 25, 2015

January 25, 2015

Number of results: 51,430

**Chemistry **

So my chem professor had a slide with a question that follows: If you combine 100 ml of 0.10 M HCl and 100 ml of 0.10 M NaOH, and find that the temperature goes up 0.67 degrees K What is ΔH° for the reac/on: OH(aq)- + H+(aq)->H2O(l)(c H2O= 4.18 J/°C sg, density of ...
*March 26, 2014 by Angely R. *

**CHEMISTRY**

the equilibrium composition of a reaction is 1.522mol CO, 1.566mol H2, 0.478mol CH4 and 0.478mol H2O and the volume of the reaction vessel is 10Litres. -What is the equation for the reaction? -Calculate the equilibrium constant for both the forward and reverse reaction?
*April 5, 2011 by Taynell*

**Chemistry**

Calculate the pH after 0.011 mol NaOH is added to 1.00 L of each of the four solutions. a) 0.100 M propanoic acid (HC3H5O2, Ka= 1.3 10-5) b) 0.100 M sodium propanoate (NaC3H5O2) c)pure H2O d) 0.100 M HC3H5O2 and 0.100 M NaC3H5O2
*March 15, 2012 by Mike*

**P. Chemistry **

A solution of HNO2 is at equilibrium: HNO2(aq) + H2O(l) ⇔ H3O+(aq) + NO2-(aq) Water is added. After the water is added, is there any shift in the equilibrium?
*March 8, 2010 by Tommy*

**chem 2**

indictae the reactant that is a bronsted lowry acid. HCN(aq) +H2O (l)---> H3O+(aq)=CN-(aq) HCN CN- H20 H30 i think it is HCN the weak acid substance which acts as a proton (H+) donor and CN the weak base? You are right. The HCN donates the proton (to H2O) so that makes HCN...
*April 30, 2007 by jane*

**statistics**

if the null hypothesis is that the mean is 3218, the alternative hypothesis is that the mean > 3228, and the sample mean is x= 3342, the sample standard deviation is s=287, the sample size is n= 42, and α= 0.01 a. calculate the z test statistic. b. what is the p-value...
*April 29, 2012 by emily*

**chemistry**

AgNO3 was dissolved in water to make 10mL of solution. Then 3.0mL of that solution was used to make a new solution with a total volume of 1.000L. What was the concentration of the silver ion in the final solution?
*October 5, 2009 by Anonymous*

**Chem**

Calculate delta H for the formation of one mole of N2O5 from the elements at 25 degrees C using the following data. 2H2 + O2 - 2H2O delta H = -571.6 kJ N2O5 + H2O - 2HNO3 deltaH = -73.7 kJ 1/2N2 + 3/2O2 + 1/2H2 - HNO3 delta H = -174.1 kJ
*April 8, 2010 by Anonymous*

**chemistry**

Calculate the pH of each of the following solutions. (a) 0.300 M propanoic acid (HC3H5O2, Ka = 1.3 10-5) (b) 0.300 M sodium propanoate (NaC3H5O2) (c) pure H2O (d) 0.300 M HC3H5O2 and 0.300 M NaC3H5O2
*December 2, 2011 by melissa*

**Chemisrty**

the freezing point of water is -1.86 degree Cm, if 5.00 g Na2SO4 is desolve at 45.0g H2o the freezing point is changed by -3.82 degree C. Calculate the Van't Hoff Factor for Na2SO4
*April 26, 2014 by saemreza*

**chemistry**

the freezing point of water is -1.86 degree Cm, if 5.00 g Na2SO4 is desolve at 45.0g H2o the freezing point is changed by -3.82 degree C. Calculate the Van't Hoff Factor for Na2SO4
*April 26, 2014 by saemreza*

**Chemistry**

Ethylene glycol, HOCH2CH2OH, is used as antifreeze. It is produced from ethylene oxide, C2H4O, by the following reaction. C2H4O(g) + H2O(l) → HOCH2CH2OH(l) Use Hess's law to obtain the enthalpy change for this reaction from the following enthalpy changes. 2 C2H4O(g) + 5 ...
*December 13, 2009 by Mariam*

**chemistry **

Ethylene glycol, HOCH2CH2OH, is used as antifreeze. It is produced from ethylene oxide, C2H4O, by the following reaction. C2H4O(g) + H2O(l) → HOCH2CH2OH(l) Use Hess's law to obtain the enthalpy change for this reaction from the following enthalpy changes. 2 C2H4O(g) + 5 ...
*October 29, 2010 by caroline*

**Chemistry**

A compound of carbon, hydrogen, and oxygen was burned in oxygen, and 2.00 g of the compound produced 2.868 g CO2 and 1.567 g H2O. In another experiment 0.1107g of the compound was dissolved in 25.0 g of water. This solution had a freezing point of -0.0894 degrees C. What is ...
*December 13, 2012 by jojop18*

**stoichiometry**

When Ba(NO3)2 and K2CrO4 (sorry, i don't know how to do subscripts, but all the numbers should be subscripts!) react in aqueous solution, the yellow solid BaCrO4 is formed. Calculate the mass of BaCrO4 that forms when 3.50 x 10^(-3) mol of solid Ba(NO3)2 is dissolved in 265 mL...
*June 5, 2008 by em*

**chemistry**

In a coffee-cup calorimeter, 1.91 g of NH4NO3 is mixed with 75.0 g of water at an initial temperature of 25.00oC. After the solution of the salt, the final temperature was 20.94oC. Assuming the solution has a heat capacity of 4.18 J/(goC) and assuming no heat loss to the ...
*October 9, 2012 by Shawn*

**Chemistry**

A few questions I don't really get and need to see the work for A 50.0 mL sample of 0.55 M benzoic acid, C6H5COOH, a weak monoprotic acid, is titrated with 0.51 M NaOH. Calculate the pH at the equivalence point. Ka of C6H5COOH = 6.5 multiplied by 10-5. What is the pH of a ...
*April 22, 2010 by Dubs*

**Hayden**

Chloroacetic acid has a relatively large equilibrium constant, so at low acid concentrations it is necessary to use the quadratic equation in order to calculate the concentrations of the aqueous species. Ka for ClCH2COOH is 1.4 ´ 10-3. For the problems that follow, consider ...
*June 19, 2010 by leona*

**Chemistry**

A chemistry student weighs out 0.123 grams of chloroacetic acid into a 250. milliliter volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.2100 moles/liter NaOH solution. Calculate the volume of NaOH solution the student will need...
*January 19, 2012 by Deborah*

**calculus**

You are using Newton's method to solve x^3-5x-2=0. If your first guess is X1=2, what value will you calculate for the next approximation X2?
*March 2, 2008 by Anonymous*

**Chemistry**

The value of H° for the reaction below is -482 kJ. Calculate the heat (kJ) released to the surroundings when 12.0 g of CO (g) reacts completely.
*April 6, 2010 by Camarra*

**chemistry**

Is it possible to calculate the value of the solubility product constant without being given any concentrations?
*April 23, 2011 by Paul*

**Chemistry**

Calculate ph value of soft drink having hydrogen ion concentration equal to 3x10^-5.
*June 29, 2011 by gagan *

**Chemistry**

Calculate ph value of soft drink having hydrogen ion concentration equal to 3x10^-5.
*June 29, 2011 by gagan *

**geometry**

The surface area and volume of a cube is the same numeric value. Calculate the side length.
*February 22, 2012 by Piggy*

**trig**

If x and y are complementary angles and 5 tan x-12=0,calculate by using a diagram the value of 2sin(squared)x+cos y.
*May 3, 2012 by Francis*

**chemisry**

Calculate how long it will take for the conctration of SO2Cl2 in the reactor in part (a) to fall to 1/4 of its initial value.
*May 30, 2013 by Anonymous*

**Financial Management**

Calculate the present value of $25,000 to be received in 5 years, assuming an opportunity cost of 10%.
*October 26, 2014 by kai*

**Chemistry **

In this lab experiment you will make 100.0 mL of a 0.100 M solution of Co(NO3)2. However you must calculate the number of moles of compound that will be needed (moles= Molarity x Liters).Then calculate the mass of Co(NO3)2 that will need to be weighed out (mass= moles x molar ...
*November 19, 2012 by Melissa*

**Chemistry (Equilibrium)**

Consider the following equilibrium system at 900°C: H20(g) + CO(g) <==> H2(g) + CO2(g) Initially 5.0 moles of H2O and 4.0 moles of CO were reacted. At equilibrium, it is found that 2.0 moles of H2 are present. How many moles of H2O remain in the mixture? Would be greatly...
*November 12, 2014 by Jessica*

**college chemistry**

A zinc-copper battery is constructed as follows: Zn | Zn+2(0.10 M) || Cu+2 (2.50 M)| Cu The mass of each electrode is 200.0 g. Each half cell contains 1.00 liter of solution. a) Calculate the cell potential when this battery is first connected. b) Calculate the cell potential ...
*April 28, 2010 by Stephanie*

**Physic- help on direction (Not that good at Englis**

Galileo figured out the equation that describes the behavior of a pendulum. If you square both sides of the equation, you will find that the slope of the line is related to the acceleration due to gravity (g). Specifically, slope = 4PI^2/g. Use your data to calculate g. How ...
*January 12, 2015 by Tara*

**chemistry**

A sulfuric acid solution at 25 °C has a density of 1.27 g/mL. A 20.0-mL sample of this acid is measured out at 25 °C, introduced into a 50-mL flask, and allowed to cool to 21 °C. The mass of the flask plus solution is then measured at 21 °C. Use the stated data, as necessary, ...
*May 25, 2009 by Zandria*

**chemistry**

OKOK I know that I have posted this question but I just don't understand the last part. 50.0 ml of a 0.0500 M solution of lead (II) nitrate is mixed with 40.0 ml of a 0.200 M solution of sodium iodate at 25°C. Calculate the Pb2+ and IO3- concentrations when the mixture comes ...
*May 16, 2007 by mel*

**Chemistry**

I can't figure out how to set up this problem...You have a large amount of 8.00 M stock solution. You need 1.80L of 3.00 M solution for an experiment. How would you prepare the desired solution without wasting any stock solution?
*October 5, 2011 by Nicole*

**Algebra**

100mL of a solution contains 30 mL of acid; this is called a 30% acid solution because part 30 ---- = ---- = 0.30. whole 100 How many milliliters of acid x would need to be added to the solution to turn it into a 50% solution ? (HInt: Adding acid increases both the volume of ...
*October 23, 2013 by Stacey*

**algebra**

A chemist has a solution that is 20% HIC and a solution that is 50% HCI. How much of each solution should be mixed to attain 300ml of a solution that is 30% HCI?
*February 21, 2012 by Susannah *

**chemistry**

The balanced equation is shown below. 2 HCl(aq) +CaCO3(s)=CaCl2(aq) +H2O(l) +CO2(g) 2.00 dm3 of a 3.00 M hydrochloric acid solution is added to the kettle (this is an excess). During the reaction 1.20 dm3 of CO2 is produced (assume 250C and 1 atmosphere) How many moles of CO2 ...
*October 27, 2014 by Abaoaqu*

**Chemistry**

Calculate the enthalpy change for: C2H4(g) + H2 --> C2H6(g) delta Hrxn: H2(g) + 1/2O2 --> H2O (l) C2H4(g) + 3O2 --> 2H20(l) + 2CO2(g) C2H6(g) + 7/2O2(g) --> 3H20(l) + 2CO2(g) I know I have to flip the third reaction but I dont know what to do next
*October 29, 2014 by Jessica*

**chemisrty**

Q4) Suppose you prepare 950 mL of a solution by dissolving 100 grams of NaCl in 900 mL of water. Assuming the density of pure water to be 1 g/mL, answer the following questions with regards to this solution: a) What is the mass percent of water in this solution? b) What is ...
*January 16, 2012 by lyan*

**probability**

Let X be a continuous random variable. We know that it takes values between 0 and 3, but we do not know its distribution or its mean and variance. We are interested in estimating the mean of X, which we denote by h. We will use 1.5 as a conservative value (upper bound) for the...
*April 22, 2014 by juanpro*

**Chemistry**

In the reaction: MnO2 + 4 HCl ---> MnCl2 + Cl2 + 2 H2O Calculate: The volume of Cl2 produced from the reaction of 10 grams of HCl with excess MnO2?
*December 13, 2010 by Darryl*

**physics**

for a damped harmonic oscillation , the equation of motion is md^2x/dt^2+(gamma)dx/dt+kx=o with m=0.025kg,(gamma)=0.07kg/s and k=85N/m. *calculate the period of motion *number of oscillation in which its amplitude will become half of its initial value *the number of ...
*February 13, 2012 by ashley*

**chemistry help asap**

Please check these thanks. 1. In a titration, 33.21 mL 0.3020M rubidium hydroxide solution is required to exactly neutralize 20.00 mL hydrofluroic acid solution. What is the molarity of the hydrofluroic acid solution? Answer: 0.502HF 2. A 35.00 mL-sample of NaOH solution is ...
*February 6, 2012 by missy*

**math**

how do you write an open statement involving an absolute value inequality when all you are given is the graph of the solution?
*September 20, 2007 by ed*

**math**

Note: in this equation the absolute value marks are symbolized by parenthesis. 2 is less than (4-x). Why would this have no solution? Thank you!!!
*October 1, 2008 by Coralia*

**Math**

Help-I just started Algebra II and I'm lost. What is the solution of 10 = absolute value of 7-3x. Please show steps so I can understand
*September 7, 2010 by Joel*

**Math-Algebra-Please check**

What is the solution of 3 times the absolute value of x + 5 <= 6 I think the answer is x <= - 3 and x >= -7 If I'm not right, could you tell me why?
*October 6, 2010 by Tanya*

**chemistry**

I am doing a boiling point problem and dont know the value of i for the equation delta T = i(kb)(m) solution contains 45.0g caffeine in 25.0 g benzene.
*December 15, 2010 by Tara*

**precalculus**

solve the inequality algebraically. write the solution in interval notation. the absolute value of x-2/3 is less than or equal to 4
*November 25, 2011 by jase*

**6th grade math**

Determine whether each value of x is a solution of the inequality 4x-5<3 a. x=0 b. x=2 c. x=-2 d. x=4 Help please *show the work and answer!!
*May 27, 2014 by mathhh HELP!! Help!!! PlEASE!!!!*

**Algebra I**

Fill in the compound inequality 4(x-6) 2(x-10) and 5(x + 2) >/ 2(x +8) with less than, greater than, at least, or at most so that the solution is only one value
*October 7, 2014 by Tonya*

**MATH**

For the following system of equations, what is the x-value of the solution? -x + 2y = 6 6y = x + 18 A. -18 B. 0 C. -6 D. 3 Confused? Still trying to work it out. Please help! Thanks
*January 20, 2015 by SkatingDJ*

**Chemistry**

when pure sodium hydroxide is dissolved in water , heat is evolved in a laboratory experiment measure a molar heat of solution of sodium hydroxide the following procedure was followed. to a calorimeter containing 300g of water at 20.0 C and 10.65g of NaOH also at 20.0 C was ...
*March 23, 2007 by jim*

**Chemistry**

I am so confused with my chemistry lab right now. We were given the following equations to work with: [Equation 1] 2 I^- + H2O2 + 2 H^+ ----> I2 + 2 H2O [Equation 9] 2S2O3^2- + I2 ----> 2I^- +S4O6^2- And During the Experiment we used the following for each reaction: T1...
*September 20, 2014 by Bev*

**math, help**

For the following set, which number has the largest absolute value? 4,-1,12,-20,19,0 Possible Answer of choice: A)0 B)19 C)-20 D)-1 wouldn't it be postive 20 but its not within the choices. What is the absolute value of -20? Absolute value is the distance to 0 on a number line...
*February 13, 2007 by jasmine20*

**P Chem**

5. The Li atom has three electrons. Measured values of the first and second ionization potentials are 5.3917 eV and 75.6400 eV, respectively. (i) Calculate the exactly correct value of the third ionization potential. Hint: What kind of species is Li+2? Give the result in ...
*November 29, 2012 by Rebecca*

**Chemistry**

How can i explain the key features of the periodic table relate to the conclusions after a titration experiment The experiment was the preperation of a standard solution of sodium carbonate and titration for the equation between hydrchloric acid and sodium carbonate Objective...
*October 11, 2010 by Paul*

**Chemistry**

A 0.60 L portion of a 1.2 M AgNO3 solution is mixed with a 0.3 L potion of a 1.2 M Na2CrO4 solution in an constant pressure calorimeter. Upon mixing, the solid Ag2CrO4 is formed and the heart released is 48.2 kJ. The specific heat of the solution is 4.18 J/C*g and the final ...
*June 9, 2010 by Kyo*

**Chemistry**

The equilibrium constant for the reaction of the weak base aniline is Kb = 4.3e-10. C6H5NH2 (aq) + H2O (l) --> C6H5NH3+ (aq) + OH- (aq). Calculate ΔG at 298 K when [C6H5NH2] = 0.250 M, [C6H5NH3+] = 1.0E-5 M, [OH-] = 0.000480 M i used the equations dG=dG^o - RTlnQ and ...
*March 25, 2014 by Brianna*

**algebra**

Joseph always throws change into a can and takes it out every two weeks. This time it is all nickels and dimes. There are six times as many dimes as nickels, and the value of the dimes is $4.95 more than the value of the nickels. How many nickels and dimes does Joseph have. (...
*April 22, 2012 by aj*

**chemistry**

Help with Beer's Law lab experiment question! So we were told to calculate the concentration of 5 standard solutions but I don't know how to do that exactly. The Concentration of the solution in flask B was .0024 M and our lambda max (max absorption) was at 515 nm. I know the ...
*September 6, 2010 by Anonymous*

**maths -urgent**

There is a manufacturing company who sold furniture's at the rate of Rs 31,300 per unit cost which is inclusive of 5% Value added tax. calculate the basic cost (exclusive of Value added tax) for 250 furniture's sold by the company.
*April 18, 2013 by anoynomous*

**Chemistry**

chemistry student weighs out 0.123 grams of chloroacetic acid (HCH2ClCO2) into a 250. milliliter volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.1200 moles/liter NaOH solution. Calculate the volume of NaOH solution the student...
*January 19, 2012 by Deborah*

**Chemistry**

A chemistry student weighs out 0.123 grams of chloroacetic acid (HCH2ClCO2) into a 250. milliliter volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.1200 moles/liter NaOH solution. Calculate the volume of NaOH solution the ...
*January 19, 2012 by Deborah*

**Chemistry**

A chemistry student weighs out 0.123 grams of chloroacetic acid (HCH2ClCO2) into a 250. milliliter volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.1200 moles/liter NaOH solution. Calculate the volume of NaOH solution the ...
*January 19, 2012 by Deborah*

**chemistry**

A solution contains naphthalene(C10H8) dissolved in hexane (C6H14) at a concentration of 14.52 % naphthalene by mass.Calculate the vapor pressure at 25 degrees C of hexane above the solution. The vapor pressure of pure hexane at 25 degrees C is 151 .
*August 5, 2010 by jay*

**Chemistry**

Calculate the solid needed to make a 250ml solution that is 0.34M in sodium cation, using sodium sulfate decahydrate. I came up with 13.685g. but how do I make that into 250ml of a solution that is0.34M in sodium cation?
*October 27, 2011 by Denise*

**oxidation**

In the reaction of hydrogen peroxide with iron (II) ion in acidic solution to form iron (III) ion and water, the oxidizing agent is... ? Fe(II) ==> Fe(III) H2O2 ==> H2O. Fe goes from +2 to +3, that is a loss of electrons, so it is oxidized (by definition, oxidation is ...
*April 19, 2007 by Christine*

**chem 12**

a) Calculate [H3O^+] in a 0.15M solution of benzonic acid, HC7H5O2(aq) having K of 6.4x10^-5. b) Calculate the per cent ionization of the HC7H5O2. I got.. Kb = [HC7H5O3][OH]/HC7H5O2 6.3x10^-5 x Kb =1.0x10^-14 Kb = 1.0x10^-14/6.3x10^-4 = 1.5x10^-10 1.5x10^-10 = (x)(x)/0.15 i'm ...
*October 11, 2011 by Sarah*

**college**

0.02 g of CaCO3 is dissolved in 1 L of water. Calculate the moles of calcium carbonate that have dissolved in the water, the moles of Ca2+ ions in solution, and the number of Ca2+ ions in solution?
*January 27, 2010 by mike*

**Chemistry**

0.02 g of CaCO3 is dissolved in 1 L of water. Calculate the moles of calcium carbonate that have dissolved in the water, the moles of Ca2+ ions in solution, and the number of Ca2+ ions in solution?
*January 27, 2010 by mike*

**Chemistry**

If you have 200 ml of a 0.1M solution of acetic acid (pka=4.75), 1. How many ml of a solution of 1.O M NaOH would you need to adjust the pH to 5.2? "Chemistry - DrBob222, Wednesday, June 29, 2011 at 8:41pm 200 mL x 0.1M = 20 mmoles. 1. ............HAc + OH^- ==> Ac^- H2O ...
*June 30, 2011 by Brayden--help Dr. Bob*

**Chemistry**

A 0.1300 g iron ore sample was dissolved in hydrochloric acid and the iron was obtained as Fe2+(aq). The iron solution was titrated with Ce4+ solution according to the balanced chemical reaction shown below. After calculation, it was found that 0.0259 g of iron from the ore ...
*March 13, 2009 by Bob*

**Chemistry**

A sample of solid Ca(OH)2 is stirred in water at 30°C until the solution contains as much dissolved Ca(OH)2 as it can hold. A 100.-mL sample of this solution is withdrawn and titrated with 5.00 X 10^-2 M HBr. It requires 48.8 mL of the acid solution for neutralization. What is...
*February 17, 2010 by Candice*

**algebra**

a chemist needs 10 liters of a 25% acid solution. the solution is to be mixed from three solutions whose acid concentrations are 10% 20% 50% how may liters of each solution should the chmist use to satisfy the following? a use as little as possible of the 50% solution b use as...
*April 26, 2008 by sandy*

**chem**

Ionization energy is defined as the minimum energy required to remove an electron from the ground state (n0) to infinity (n∞). Determine the wavelength of radiation required to ionize the hydrogen electron from the n = 2 energy level. Calculate the energy (Joules) ...
*October 2, 2006 by Mary*

**Science**

Chemistry Enthalpy Calculations? Given the equation: CaO + H2O ----> Ca(OH)2 A 1 g sample of CaO is dissolved in 100 ml water with density 1.00g/ml. The temperature rise is 3.7 degrees C. The specific heat is 4.00 J/g*deg. 1. Calculate the heat (in J) absorbed/given off by ...
*October 18, 2012 by Pablo*

**Chemistry**

Predict the standard cell potential and calculate the standard reaction Gibbs free energy for galvanic cells having the following cell reactions: 2H2+O2=2H2O in acidic solution 2H2+O2=2H2O in basic solution I understand the idea behind the problem, but I am not sure how the ...
*March 10, 2014 by Anonymous*

**statistics**

given that u=100 X=91, s=27, and N=30 (a)calculate t. (b)write a sentence interpreting the value of t as a two- tailed test. (c)write a sentence interpreting the value of t as a one-tailed test.
*April 24, 2011 by sassy*

**financial 200**

Write a 200-300 word description of the four time value of money concepts: present value, present value of an annuity, future value, and future value of annuity. Descrive the characteristics of each concept and provide an example of when each of when each would be used.
*July 23, 2010 by Chris*

**chemistry**

Which solutions are acidic? (Assume all solutions are at 25°C. Kw = 1.0 x 10-14 at 25°C.) A. A solution with [H+] = 9.4 x 10-6 B. A solution with [H+] = 5.5 x 10-10 C. A solution with pH = 6.1 D. A solution with [OH-] = 6.4 x 10-7 E. A solution with [OH-] = 2.0 x 10-6
*October 8, 2010 by Ceci*

**Chemistry**

I need help splitting this reaction into 1/2 reactions 3I2(s) + 2MnO2(s)+8 OH-(aq)<-> 6I-(aq) + 2MnO4-(aq) + 4H2O(l) Can you identify which components are oxidised, which are reduced and those that undergo no change? Can you identify which components are oxidised, which ...
*April 19, 2007 by amy*

**Solving Rational Equations**

100mL of a solution contains 30 mL of acid; this is called a 30% acid solution because part 30 ---- = ---- = 0.30. whole 100 How many milliliters of acid x would need to be added to the solution to turn it into a 50% solution ? (HInt: Adding acid increases both the volume of ...
*October 23, 2013 by Stacey*

**chemistry**

A glucose solution contains 55.8g of glucose (C6H12O6) in 455g of water. Calculate the freezing poing and boiling point of the solution. (Assume a density of 1.00 g/ml for water. This what I did, I got moles of C6H12O6, 0.89 moles C6H12O6 then I got the mass of the solution ...
*November 4, 2011 by Monique*

**ap chem**

calculate the enthalpy of formationof solid MgOH2, given the following data: 2Mg(s) + O2(g)-> 2MgO(s) heat:-1203.6 Mg OH2(s) -> MgO(s) +H2O(l) heat: 37.1 2H2(g)+ O2(g) -> 2H2O(l) heat: -571.7 what equation would they want the three equations to develop into and which ...
*October 4, 2007 by lily*

**Chemistry**

A sample of ethanol, C2H5OH, weighing 2.84 g was burned in an excess of oxygen in a bomb calorimeter. The temperature of the calorimeter rose from 25.00°C to 33.73°C. If the heat capacity of the calorimeter and contents was 9.63 kJ/°C, what is the value of q for burning 1.28 ...
*June 7, 2011 by Lance*

**chemistry**

Calculate the concentration, in percent by mass, of a refrigerant brine solution which is 4.03 M in NaCl with a density of 1.116 g mL-1.
*November 9, 2007 by keely*

**chemistry**

Calculate the Ka of nitrous acid if a 0.200 mol/L solution at equilibrium at SATP has a percent ionization of 5.8%
*April 5, 2008 by Laura*

**chemistry**

Calculate how much energy will be released when 11.11g of calcium chloride are dissolved in 100ml of solution
*May 2, 2009 by Mandy*

**chemistry**

Commercial bleach contains 5.25% (by mass) of NaClO in water. It has a density of 1.08 g/mL. Calculate the molarity of this solution.
*March 3, 2010 by Drew*

**Chemistry**

Calculate the solubility of silver iodide in a 1.0 M sodium cyanide solution. Ksp = 8.5 x 10^-17 for AgI Kform = 2.5 x 10^5 for Ag(CN)2
*April 7, 2010 by Erin*

**Chemistry**

Calculate the freezing- and boiling-point changes for a solution containing 12.0 g of naphthalene (C10H8) in 50.0 g of benzene.
*May 2, 2010 by Mariah*

**chemistry**

calculate the percent composition or w/v% of 3x10 to the 2nd power mL solution containing 15g of glucose
*May 4, 2010 by Quentin*

**chm**

If 0.0490g of AgIO3 DISOLVES per liter of solution, calculate the solubility product constant.
*June 27, 2010 by ami*

**Chemistry**

What formula do I use to calculate the mass of KCl that is required to make 625 mL of a 0.200 M solution?
*July 25, 2010 by Norma*

**College Chem**

Calculate the number of grams required to make 250 mL of a 0.020 M KIO3 solution.
*October 3, 2010 by Kelli *

**Chemistry**

Calculate the freezing point of each of the solution 75.0 of glucose,C6H12O6 , added to 9.30×10−2 of water.... Please help
*December 6, 2010 by Garrett*

**Chemistry**

Calculate the pH of a solution at the endpoint of a titration involving 25.00 mL of CH3COOH at unknown concentration, and 21.40 mL of 0.100 M NaOH
*December 15, 2010 by Lisa*

**science**

You add 12.5 mL of 4.15 acetic acid to 25.0 mL of 1.00 M NaOH. Calculate the hydronium ion concentration and pH of the resulting solution.
*March 7, 2011 by Bill*

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