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May 27, 2015

Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

Chemistry
100 ml graduated cylinder containing 50 ml of water, drop 100g piece of brass into the water what height does the water rise in the graduated cylinder?
Friday, February 20, 2015 at 8:17pm

Chemistry
An automobile tire has a maximum rating of 38.0 psi (gauge pressure). The tire is inflated (while cold) to a volume of 11.8 Liters and a gauge pressure of 36.0 psi at a temperature of 12.0 Celsius. While driving on a hot day, the tire warms to 65.0 Celsius and it's volume ...
Friday, February 20, 2015 at 8:10pm

chemistry
Al2(SO3)3 + 6NaOH ¨ 3Na2SO3 + 2Al(OH)3 If this reaction begins with 10 g Al2(SO3)3 and 10 g NaOH, what is the theoretical yield in grams Al(OH)3 and what is the limiting reactant?
Friday, February 20, 2015 at 6:14pm

chemistry
I have questions but I don't understand this passage. Could you give a summery? Here are the question 1. One problem the researchers faced was an uncertainty about whether the signals observed in certain mass spectrometry data were, in fact, due to lead isotopes. Explain ...
Friday, February 20, 2015 at 5:05pm

Chemistry
The balanced net ionic equation resulting from addition of aqueous hydrochloric acid to solid chromium(III) hydroxide is: A. Cr(OH)3 (s) + 3 HCl (aq) 3 H2O (l) + CrCl3 (aq) B. Cr(OH)3 (s) + 3 Cl- (aq) 3 OH- (l) + CrCl3 (aq) C. Cr(OH)3 (s) + 3 H+ (aq) + 3 Cl- (aq) 3 H2O (l) + ...
Friday, February 20, 2015 at 2:50pm

Chemistry
what is the trend in the atomic radii as the atomic number increases across a period? What is the exception to this trend? I know the radius decreases as you go from left to right, but I can't figure the exception, I read somewhere that it's the noble gasses but I'...
Friday, February 20, 2015 at 2:13pm

chemistry
Describe how to prepare 1 L of a 0.5 M solution of cobalt chloride hexahydrate (CoCl2 6H2O). Be sure to identify the labware shown above (flask and a scale), explain your reasoning, and show any calculations.
Friday, February 20, 2015 at 2:03pm

Chemistry
Propane gas (C3H8) burns completely in the presence of oxygen gas (O2) to yield carbon dioxide gas (CO2) and water vapor (H2O). Write a balanced equation for this reaction. Assuming that all volume measurements occur at the same temperature and pressure, how many liters of ...
Friday, February 20, 2015 at 1:50pm

chemistry
The Russian Mir space station used a chemical oxygen generator system to make oxygen for the crew. The system ignited a tube of solid lithium perchlorate (LiClO4) to make oxygen and lithium chloride (LiCl): LiClO4 (s)  2O2 (g) + LiCl (s) If you have 500 g of LiClO4, ...
Friday, February 20, 2015 at 1:48pm

Chemistry
Use this reaction for this question: 4NH3 (g) + 2O2 (g) 4NO (g) + 6H2 (g); H = -905 J. Which statement is true about the reaction above? A. G is negative at all temperatures. B. S is negative and G is positive. C. S is negative and G is negative. D. G is positive at all ...
Friday, February 20, 2015 at 1:26pm

Chemistry
What is a molecular dipole moment? A. A separation of charge characterizing a nonpolar covalent bond B. A separation of charge forming a positive and a negative end of a molecule C. The arrangement of charges around an atom in a nonpolar molecule D. A net cancellation of ...
Friday, February 20, 2015 at 12:27pm

organic chemistry
Provide a structure for the following compound: C9H10O3; IR: 2400–3200, 1700, 1630 cm–1; 1H NMR: δ 1.53 (3H, t, J = 8 Hz); δ 4.32 (2H, q, J = 8 Hz); δ 7.08, δ 8.13 (4H, pair of leaning doublets, J = 10 Hz); δ 10 (1H, broad, disappears with ...
Friday, February 20, 2015 at 9:17am

chemistry
chemical formulae for naphthalene and benzoic acid
Friday, February 20, 2015 at 3:12am

chemistry
In a constant-pressure calorimeter, 65.0 mL of 0.330 M Ba(OH)2 was added to 65.0 mL of 0.660 M HCl. The reaction caused the temperature of the solution to rise from 21.91 °C to 26.41 °C. If the solution has the same density and specific heat as water, what is ÄH ...
Friday, February 20, 2015 at 1:52am

Chemistry
what is the trend in the atomic radii as the atomic number increases across a period? What is the exception to this trend? I know the radius decreases as you go from left to right, but I can't figure the exception, I read somewhere that it's the noble gasses but I'...
Friday, February 20, 2015 at 1:44am

chemistry
A particular photon has a wavelength of approximately 2 x 10-7m. What is the energy, in joules, associated with this photon? A. More information is needed. B. 4 x 10-32 C. 1 x 10-18 D. 1 x 1018 E. 1.5 x 1015
Friday, February 20, 2015 at 12:11am

chemistry
Given the following information about electronegativity, which binary compound would form covelant bonds with the greatest polarity? Element Electronegativity H 2.1 Li 1.0 S 2.5 Al 1.5 F 4.0 Cl 3.0 A. HCl B. LiF C. H2S D. AlH3
Thursday, February 19, 2015 at 9:56pm

Chemistry
A 100.0 g sample of ice at -15°C is heated until it is converted to water vapour at 120.0°C. Calculate the total energy change.
Thursday, February 19, 2015 at 9:22pm

Chemistry
In a coffee-cup calorimeter, 1.50 g of NH4NO3 is mixed with 72.0 g of water at an initial temperature of 25.00°C. After dissolution of the salt, the final temperature of the calorimeter contents is 23.65°C. Assuming the solution has a heat capacity of 4.18 J/°C&...
Thursday, February 19, 2015 at 9:07pm

Chemistry
"Find the total energy lost by the contents of a Styrofoam picnic cooler when a 3.60 kg block of ice placed inside the cooler completely melts (at 0 Celsius). The ice had an initial temperature of -10.00 Celsius." My ans are q1=72360J n q2=21672 q=94032J But one ...
Thursday, February 19, 2015 at 8:31pm

Chemistry
"Find the total energy lost by the contents of a Styrofoam picnic cooler when a 3.60 kg block of ice placed inside the cooler completely melts (at 0 Celsius). The ice had an initial temperature of -10.00 Celsius." I did this question and i got 73080J but I'm not ...
Thursday, February 19, 2015 at 7:09pm

Chemistry
Suppose a galvanic cell contains one nickel electrode and one copper electrode. At 25°C, nickel has a negative reduction potential and copper has a positive reduction potential. At which electrode will reduction occur? Explain. I believe the copper will be oxidized and the...
Thursday, February 19, 2015 at 6:20pm

chemistry
I have a lab finished and I have to find the dehydrated sample (show calculations) and the value of n (show calculations). I just need to know how I go about finding these answers using my data?
Thursday, February 19, 2015 at 4:48pm

Chemistry
An unknown gas sample is collected in a 255mL container at 25 C and 755 mmHg. How many moles of gas are present? show solution please so i can learn:D
Thursday, February 19, 2015 at 4:45pm

chemistry
Find the mass in grams of a 240 ml sample of dry air at a pressure of 750 mmHg and a temperature of 19 degrees celsius.
Thursday, February 19, 2015 at 4:44pm

chemistry
Epsom salts is magnesium sulfate heptahydrate. If a student takes 2.50 g of Epsom salts and heats it to drive off the water, how much mass should the student expect to lose? ( I know that hepta is 7 but that's still not making sense to me)
Thursday, February 19, 2015 at 4:39pm

chemistry
How many grams of water are required to completely hydrolyze 0.54 grams of lidocaine? What type of be equation should be used?
Thursday, February 19, 2015 at 4:11pm

organic chemistry
Provide a structure for the following compound: C9H10O3; IR: 2400–3200, 1700, 1630 cm–1; 1H NMR: δ 1.53 (3H, t, J = 8 Hz); δ 4.32 (2H, q, J = 8 Hz); δ 7.08, δ 8.13 (4H, pair of leaning doublets, J = 10 Hz); δ 10 (1H, broad, disappears with ...
Thursday, February 19, 2015 at 3:58pm

Chemistry
A balloon filled with 1.35 atm of dimethyl ether gas and 5.25 atm of oxygen gas at 27 °C has an initial volume 2.00L They react according to the following reaction: C2H6O (g) + 3 O2 (g) -> 2 CO2 (g) + 3 H2O (g) The system is allowed to back cool down to 27 °C ...
Thursday, February 19, 2015 at 3:16pm

Chemistry
Calculate the rms speed of Br2 molecules at 23 °C and 1.00 atm. What is the rms speed of Br2 at 23 °C and 1.50 atm?
Thursday, February 19, 2015 at 3:00pm

Chemistry
At standard temperature and pressure, a 1.00-mol sample of argon gas is vented into a 22.4-L rigid box that already contains 1.00 mol of nitrogen gas. We would expect the argon gas to:
Thursday, February 19, 2015 at 2:58pm

chemistry
Given the following information about electronegativity, which binary compound would form covelant bonds with the greatest polarity? Element Electronegativity H 2.1 Li 1.0 S 2.5 Al 1.5 F 4.0 Cl 3.0 A. HCl B. LiF C. H2S D. AlH3
Thursday, February 19, 2015 at 2:02pm

Chemistry
A 11.6 g sample of an unknown metal was heated to 100.0 oC and then added to 25.0 g of water at 23.0 degrees Celsius in an insulated calorimeter. At thermal equilibrium, the temperature of the water in the calorimeter was 24.8 degrees Celsius. What is the heat absorbed or lost...
Thursday, February 19, 2015 at 1:59pm

Chemistry
In an acid-base neutralization reaction 25 mL of 0.4 M NaOH reacts with 50.00 mL of H2SO4 solution. Calculate the concentration of the H2SO4 solution?
Thursday, February 19, 2015 at 11:44am

Chemistry
A reaction in which X and Y form products was found to be second order in X and first order in Y. By what factor will the rate of the reaction change if [X] is doubled and [Y] is tripled? a. 10 b. 12 c. 20 d. 2
Thursday, February 19, 2015 at 11:05am

chemistry
If I have 298 mL of a 0.8 M solution of NaBr, what will the concentration be if I add 425 mL of water?
Thursday, February 19, 2015 at 9:27am

Chemistry
Strong base is dissolved in 535 mL of 0.200 M weak acid (Ka = 3.16 × 10-5) to make a buffer with a pH of 4.04. Assume that the volume remains constant when the base is added. HA (aq)+ OH^-(aq) -> H2O(l) + A^-(aq) Calculate the pKa value of the acid and determine the ...
Thursday, February 19, 2015 at 4:19am

chemistry
An aqueous solution at 25 °C is 10.0% HNO3 by mass and has a density of 1.051 g/mL. What is the pH?
Thursday, February 19, 2015 at 2:15am

chemistry
(2*10^3g/8.165g)/(0.071cm^3/0.051cm^3)
Thursday, February 19, 2015 at 1:32am

Chemistry
Human bodies maintain their balance (homeostasis) through a series of equilibria. An important equilibrium involves calcium ion because Ca2+ is important for muscle contractions in the heart as well as for strong bones. Bone is a complex tissue consisting of living cells and ...
Thursday, February 19, 2015 at 12:50am

Chemistry
A 500.0 mL sample of saturated nickel(II) phosphate solution was analyzed spectrophotometrically and found to contain 1.88 × 10-5 g of nickel. (a) Determine the molarity of the nickel(II) phosphate solution. (b) Calculate the solubility product constant, Ksp for nickel(...
Thursday, February 19, 2015 at 12:49am

Chemistry
The solubility of insoluble substances changes depending on the nature of the solution. Below are two solutions in which Cu(OH)2 is dissolved; in each case, the solubility of Cu(OH)2 in those solutions is not the same as it is in pure water. (a) For each Cu(OH)2 solution below...
Thursday, February 19, 2015 at 12:49am

chemistry
If BH3 formed the trigonal planar molecule shown in the image below, which statement would best describe BH3? A. Boron does not contain a complete octet of electrons. B. BH3 would orient in an electric field. C. BH3 is a polar molecule. D. BH3 forms four bonds around the ...
Wednesday, February 18, 2015 at 11:00pm

chemistry
Consider a solution containing 0.47 M HOCl and 0.67 M NaOCl for the next two questions. The Ka for HOCl = 3.5E-8. What is the pH of this solution? Now calculate the pH of this solution after 0.15 mol of NaOH is added to 1.00 L of the solution. Assume that the volume does not ...
Wednesday, February 18, 2015 at 9:41pm

Chemistry
The reaction of NO and O2 produces NO2. 2 NO(g) + O2(g) „_ 2 NO2(g) The reaction is second-order with respect to NO(g) and first-order with respect to O2(g). At a given temperature, the rate constant, k, equals 4.7 x 10^2 M^¡V2s^¡V1. What is the rate of ...
Wednesday, February 18, 2015 at 8:57pm

Chemistry
For a certain reaction, the activation energy is 52.1 kJ/mole. By what ratio will the rate constant change if the temperature is decreased from 175C to 75C?
Wednesday, February 18, 2015 at 8:13pm

Quick chemistry help
What is the precipitate color for Na3PO4+CaCl2?
Wednesday, February 18, 2015 at 7:19pm

Chemistry
You want to determine the heat of reaction when a sodium chloride solution is formed using a 10.0 g sample of NaCl(s) and 50.0 mL of water in a coffee cup calorimeter. Which of the following equations would you use? Assume the specific heat of the solution is the same as the ...
Wednesday, February 18, 2015 at 4:20pm

chemistry
Calculate the specific rotation for Compound A, whose observed rotation was (+) 45.0 for a solution made from 0.400 g dissolved in 5 mL of chloroform solvent. The cell path length was 10 cm.
Wednesday, February 18, 2015 at 1:53pm

chemistry
Why is there a decrease in electron affinity going from lithium to sodium? A. There is a stronger nuclear charge, with no additional shielding electrons or number of shells. B. There are fewer spaces in the valence shell in which to place the added electron. C. The nucleus has...
Wednesday, February 18, 2015 at 1:38pm

chemistry
ho electrons are there in a silicon atoms?
Wednesday, February 18, 2015 at 12:39pm

chemistry
How many moles of water does it take to make 477g of lithium hydroixide
Wednesday, February 18, 2015 at 11:17am

Chemistry
Which is true of a balanced combustion reaction? Atoms are conserved. Mass is conserved. Both are correct. confused
Wednesday, February 18, 2015 at 11:08am

chemistry
How many Liters of H2 are produced if 3 liters of a 4M solution of H3PO4 decompose at 25oC and 1.05atm?
Wednesday, February 18, 2015 at 11:08am

Organic Chemistry
A 1.0 gram sample of aspirin will dissolve in 300 mL of water and in 17 mL of chloroform at 25 deg C. a. What is the solubility of aspirin in each solvent expressed in g/mL? (show your calculations) I don't know where to start, does the molecular weight come into play (180...
Tuesday, February 17, 2015 at 10:08pm

chemistry
In a 1L beaker, 203mL of 0.307 M ammonium chromate was mixed with 137mL of 0.269 M chromium(iii) nitrite. 3(NH4)2CrO4 + 2Cr(NO2)3 -> Cr2(CrO4)3 + 6NH4NO2 If the percent yield of the reaction was 88.0 %, what mass of solid product was isolated?
Tuesday, February 17, 2015 at 9:30pm

chemistry
In a 1L beaker, 203mL of 0.307 M ammonium chromate was mixed with 137mL of 0.269 M chromium(iii) nitrite. 3(NH4)2CrO4 + 2Cr(NO2)3 -> Cr2(CrO4)3 + 6NH4NO2 If the percent yield of the reaction was 88.0 %, what mass of solid product was isolated?
Tuesday, February 17, 2015 at 9:26pm

Chemistry
If all the H2O2 in 25mL of a 3% solution of H2O2 decomposed, calculate the diameter of a sphere that would contain the resulting O2 at 1 atm and 296K. I understand how to do the problem if I have moles but I am not sure how to get moles. I thought n=0.075moles because 3% ...
Tuesday, February 17, 2015 at 7:43pm

AP Chemistry
A student titrates 25.0 mL of a 0.100 M solution of acetic acid with a 0.100 solution of sodium hydroxide. Calculate the pH at the equivalence point.
Tuesday, February 17, 2015 at 7:30pm

chemistry
Why material properties vary in spite of the similarity in crystalline form?
Tuesday, February 17, 2015 at 5:28pm

chemistry
Predict if a precipitate will form when 20.00 mL of the 50% saturated solution is mixed with 20.00 mL of 0.0100M of the following solutions.? the saturated solution is : BaCO3, it has the Ksp of 5.1 x 10^-9 the solubility is 7.1 x 10^-5 M. I don't know how to do this. I am...
Tuesday, February 17, 2015 at 5:10pm

chemistry
Consider the reaction of 14.20ml of 0.141 M H3PO4 and 0.0521 M Ba(OH)2. 2H3PO4 + 3Ba(OH)2 ->Ba3(PO4)2 + 6HOH What volume of Ba(OH)2 is required to completely react with the H3PO4?
Tuesday, February 17, 2015 at 4:23pm

chemistry
Consider the reaction of 14.20ml of 0.141 M H3PO4 and 0.0521 M Ba(OH)2. 2H3PO4 + 3Ba(OH)2 ->Ba3(PO4)2 + 6HOH What volume of Ba(OH)2 is required to completely react with the H3PO4?
Tuesday, February 17, 2015 at 4:22pm

chemistry
By titration, 26.7 mL of aqueous H2SO4 neutralized 26.2 mL of 0.028 M LiOH solution. What was the molarity of the aqueous acid solution?
Tuesday, February 17, 2015 at 3:54pm

chemistry
What pairs of ions produce similar colours in the flame test? Use your periodic table of elements to explain the reason for this. The pairs with similar colours were Ba2+ and Cu2+, and Sr2+ and Li+. Ba and Cu had light green-ish colours, and Sr and Li had red colours. I don&#...
Tuesday, February 17, 2015 at 1:37pm

Chemistry and physics
What causes a red glow when the iron and sulphur mixture is heated?
Tuesday, February 17, 2015 at 1:30pm

Chemistry
How do I get the answer to ?mass, 200 cm3volume, 6.843 g/ml=
Tuesday, February 17, 2015 at 12:03pm

chemistry
4g of a mixture of CaCO3 and sand is treated with an excess of HCl and 0.88g of CO2 is produced. What is the percentage of CaCO3 in the mixture
Tuesday, February 17, 2015 at 3:51am

Chemistry
What is the name of the substance with formula Cu(H2O)6SO4?
Tuesday, February 17, 2015 at 2:34am

chemistry
describe the predominant forces that exist between molecules of the noble gases. Arrange the noble gases in a predicted order of increasing boiling point (lowest first) and explain the reason for the order
Monday, February 16, 2015 at 10:19pm

Chemistry
Why is the slowest elementary step "the rate determining step"?
Monday, February 16, 2015 at 10:06pm

chemistry
What will be the final temperature of 650 g of water initially at 5.5°C if it is heated by burning 7.5 g of carbon to carbon dioxide. The molar heat of reaction is -393.5 kJ/mol. I do not understand how to do this question
Monday, February 16, 2015 at 9:47pm

chemistry - dilution factor
I have 4 ml of eluent from SPE and I brought the volume up to 5 ml using the solvent. The eluent was ran in UV for Quant analysis. Is the dilution factor 0.8 because it would be "4 in 5"?
Monday, February 16, 2015 at 9:21pm

chemistry
Calculate the change in enthalpy produced by dissolving 14.3 g of NaOH in 65.0 g of water if the temperature increases 49.1°C and the specific heat of water is 4.18 J/g°C I believe you multiply 4.18, 65.0, and 49.1. Am I correct
Monday, February 16, 2015 at 8:55pm

Chemistry
Are halogens and non-metals metal or non-metals? I think they're both non-metals
Monday, February 16, 2015 at 7:44pm

chemistry
A student is performing an experiment to find the density of water. She obtains a 100ml beaker, which weighs 53.257 grams, and she fills it with 60 mL of water. The temperature of the water is 25.5 degrees celsius (room temperature). Again the student takes the weight of the ...
Monday, February 16, 2015 at 6:44pm

chemistry
If a reaction has a percentage yield of 83.0%, what mass of methane can be obtained from 1150 g of carbon? 2 C(s) + 2 H2O(l) CH4(g) + CO2(g) *Answer in grams*
Monday, February 16, 2015 at 2:13pm

Chemistry
Calculate the number of grams of propane (C3H8) consumed if 17.7 g of water is produced according to the reaction: C3H8(g)+5O2(g)=3CO2(g)+4H2O(g)
Monday, February 16, 2015 at 12:55pm

Chemistry
How much potassium chloride in grams is needed to prepare 1500ml solution of 3% kcl solution? This is my answer: 3x1500=4500 4500÷100=45 Answer is 45gm
Monday, February 16, 2015 at 6:37am

chemistry
A 100.0 ml aqeuous solution that contains 0.50 g of hemoglobin has an osmotic pressure of 0.00178 atm. What is the molar mass of hemoglobin?
Monday, February 16, 2015 at 3:36am

Chemistry
Posted by Cyndy on Sunday, February 15, 2015 at 6:45pm. How many grams of ammonium chloride are needed to raise the ammonia level 5 ppm in a 300 gallon system? Now, I have worked the problem so many times I have confused myself I think. I keep getting 2 different answers ...
Monday, February 16, 2015 at 12:56am

chemistry
A freezing point depression experiment was conducted using cyclohexane as the solvent. The freezing point of pure cyclohexane is 6.60°C and the freezing point depression constant is 20.00°C/m. The freezing point of a solution containing 0.135 g of an unknown ...
Monday, February 16, 2015 at 12:50am

Chemistry
Nitrogen dioxide reacts with carbon monoxide to produce nitrogen monoxide and carbon dioxide in the reaction, . The first step in the reaction is proposed to be two NO2 molecules colliding to form NO3 and NO. The NO3 intermediate then reacts with CO to form CO2. What is the ...
Monday, February 16, 2015 at 12:48am

chemistry
A student collects gas over water after reacting sodium bicarbonate with hydrochloric acid. The watwr in the collector is the same both inside and out. The partial pressure of the carbon dioxide gas collected is 740 atm.if the temperature at the time of the experiment is 25c ...
Sunday, February 15, 2015 at 11:44pm

chemistry
Calculate the pH of a saturated solution of Sr(OH)2. The Ksp for Sr(OH)2 is 3.2x10^-4.
Sunday, February 15, 2015 at 9:45pm

Chemistry
What is the percent by mass of NaHCO3 and KCl in the mixture.
Sunday, February 15, 2015 at 9:30pm

Chemistry
Can someone please explain to me what was John Dalton's experiment that led to his atomic theory? I know it's the electrolysis of water, but I'd appreciate if someone could explain in detail.
Sunday, February 15, 2015 at 8:14pm

Chemistry
how many grams of ammonium chloride are needed to raise the ammonia level 5 ppm in a 300 gallon system?
Sunday, February 15, 2015 at 6:45pm

Organic Chemistry
Gas Chromatography: The internal standard technique is used. A volatile component which does not interfere with the GC analysis (i.e. it gives a separate peak) is added to the sample which is then analyzed. For example, 10.0 mg of D was added to 50.0 mg of the mixture of A, B...
Sunday, February 15, 2015 at 4:36pm

chemistry
suppose 0.0139g of HNO3 is dissolved in 625 mL of aqueous solution. what is the pH
Sunday, February 15, 2015 at 4:32pm

Chemistry
Why is the gas oils fraction more viscous than the kerosene fraction
Sunday, February 15, 2015 at 4:02pm

Chemistry
Calculate the molar extinction coefficients for carotene and chlorophyll using the peaks of highest absorption and Beer’s law.Show your calculations.basically solve for e A = ebc Carotene (Yellow) = Highest peak 450 nm and 0.455 absorption A = ebc 0.455 = e*1cm*c? 0.455...
Sunday, February 15, 2015 at 4:00am

chemistry
Two-stroke motor boat engines emit a large amount of partially burned fuel into the water. One of the more common chemicals is phenanthrene . The degradation half-life of phenanthrene is about 7.30 days in clear surface waters. If a motor boat emits 97.0 g of phenanthrene ...
Sunday, February 15, 2015 at 12:55am

chemistry
Based on reaction kinetics, which of the following pairs of reactions and reaction rate equations represent elementary reactions? You may choose more than one reaction. Ti + 2Cl2 = TiCl4 Rate = k[Ti][Cl2] 2SO2 + O2 = 2SO3 Rate = k[O2][SO2]2 Na2S + CuSO4 = CuS + Na2SO4 Rate = k...
Saturday, February 14, 2015 at 11:49pm

chemistry
The activation energy of a reaction is typically determined by calculating the rate constant for the reaction at two temperatures and then manipulating the Arrhenius equation. If you determine the reaction rate constants for a particular reaction to be 0.0650 /s at 25.0 C and ...
Saturday, February 14, 2015 at 11:48pm

chemistry
Suppose 100 moles of a chemical is spilled into a lake. After 15.0 days, the total amount of the chemical in the lake 3.50 moles. Assuming that the reaction followed first order kinetics and no chemical was lost due to advection or volatilization, then what is the rate ...
Saturday, February 14, 2015 at 11:48pm

chemistry
Radioactive waste is difficult to dispose of due to the long time periods needed before the radiation effectively disappears. The US protocol is to store the waste for 10 half-lives of the material after which the waste is no longer considered radioactive. After this time, ...
Saturday, February 14, 2015 at 11:47pm

Chemistry
1.2048g sample of impure Na2CO3 is dissolved and allowed to react with a solution of CaCl2 resulting CaCO3 after precipitation, filtaration and drying was found to weight 1.0362g. calculate the percentage purity of Na2CO3
Saturday, February 14, 2015 at 11:45pm

Chemistry
6 mol sample of Cu2S is roasted in excess O2 to yield Cu metal and SO2. Calculate the mass of Cu metal produced
Saturday, February 14, 2015 at 10:41pm

chemistry
In which of the following reactions is ΔE closest in value to ΔH? HNO3(aq) + Na2(CO3)(aq) = NaNO3(aq) + H2O(l) + CO2(g) KClO3(s) = KCl(s) + (3/2)O2(g) HCl(aq) + NaOH(aq) = H2O(l) + NaCl(aq) Na(s) + H2O(l) = NaOH(aq) + (1/2)H2(g)
Saturday, February 14, 2015 at 8:46pm

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