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Recent Homework Questions About Chemistry

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chemistry
write the reaction of propanal reacting with: CH3CH2NH2 and CH3MgClthen H2O/H+
Tuesday, December 11, 2012 at 6:30pm

chemistry
hey guys need some help here!!! if 0.250mol of CO and 0.250mol of H2O were combined in a 125mL flask and the reaction allowed to reach equilibrium . Kc= 1.56. write the equ expression and calculate each substance Co(g) +H2O(g) .... Co2(g) +H2(g)
Tuesday, December 11, 2012 at 6:18pm

chemistry
The theoretical yield of a reaction is 78.5 grams of product and the actual yield is 66.3 grams. What is the percent yield?
Tuesday, December 11, 2012 at 5:42pm

Chemistry
The pressure of a 27o mL sample of gas is 102 kPa. What would be the pressure if the volume were increased to 378 mL?
Tuesday, December 11, 2012 at 5:28pm

chemistry
* A 50 gram sample of an unknown metal warms from 18 to 58 after absorbing 800 joules of energy. what is the specific heat of the metal? *copper has a specific heat of 0.387 j/g degree celsius. what is the mass of a piece of copper that undergoes a 21.0 C temperature change ...
Tuesday, December 11, 2012 at 5:23pm

chemistry
2NaClO2---> 2NaCl + 3O2 if 3.85 grams of NaClO3 react, how many moles of O2 are created?
Tuesday, December 11, 2012 at 5:22pm

Chemistry
Is this reaction exothermic or endothermic? Fe(NO3)3+ NaSCN
Tuesday, December 11, 2012 at 5:03pm

Chemistry
The ΔHof of gaseous dimethyl ether (CH3OCH3) is –185.4 kJ/mol; the vapour pressure is 1.00 atm at –23.7oC and 0.526 atm at –37.8oC. a) Calculate ΔHovap of dimethyl ether. b) Calculate ΔHof of liquid dimethyl ether Any idead how to calculate for ...
Tuesday, December 11, 2012 at 3:58pm

chemistry
If the 12.5ml of NaOH solution is required to react completely with 0.300g of KHP (Potassium Hydrogen Phthalate, 204.2g/mol). What is the molarity of NaOH?
Tuesday, December 11, 2012 at 3:57pm

Chemistry
Consider a 0.71 M solution of each of the following salt dissolved in distilled water. Will the solution by basic, neutral, or acidic? KI= NH4NO2= (CH3CH2)3NHNO2= (CH3CH2)2NH2ClO4=
Tuesday, December 11, 2012 at 3:33pm

Chemistry
a 0.451 L solution of 1.71 ascorbic acid (ka1=7.9E-5, ka2=1.6E-12) is titrated with 1.35 M NaOH. What is pH when 0.9540 L of NaOH is added?
Tuesday, December 11, 2012 at 3:30pm

chemistry
The concentration of ammonium phosphate, (NH4)3PO4, is 1.60 M. What is the concentration of ammonium ions in solution?
Tuesday, December 11, 2012 at 1:22pm

Chemistry
Health regulations stipulate that the amount of arsenate in drinking water be no grater than 10 parts per billion (ppb) arsenic. If the arsenic present is arsenate, AsO4^-3, what mass of sodium arsenate would be present in a 1.00 L sample of drinking water that just meets the ...
Tuesday, December 11, 2012 at 12:12pm

Chemistry
In the "Methode Champenoise," grape juice is fermented in a wine bottle to produce sparkling wine. The reaction is given below. C6H12O6(aq)--> 2 C2H5OH(aq) + 2 CO2(g) Fermentation of 746 mL grape juice (density = 1.0 g/cm3) is allowed to take place in a bottle ...
Tuesday, December 11, 2012 at 9:27am

Science- Chemistry
Determine the type of bonding in each substance. a. Zinc, Zn (s) b. Propane, C3H8 (l) c. Calcium Carbonate, CaCO3 (s)
Tuesday, December 11, 2012 at 9:16am

Chemistry HELP
A 0.75–L bottle is cleaned, dried, and closed in a room where the air is 22oC and 44% relative humidity (that is, the water vapour in the air is 0.44 of the equilibrium vapour pressure at 22oC). The bottle is brought outside and stored at 0.0oC. just this question cause i...
Tuesday, December 11, 2012 at 7:53am

Chemistry
A 0.75 L bottle is cleaned, dried, and closed in a room where the air is 22°C and 47% relative humidity (that is, the water vapor in the air is 0.47 of the equilibrium vapor pressure at 22°C). The bottle is brought outside and stored at 0.0°C. My question is what ...
Tuesday, December 11, 2012 at 7:29am

Chemistry
The equation for photon energy, , is where = 6.626×10−34 (Planck's constant) and = 3.00×108 (the speed of light). What is the wavelength, , of a photon that has an energy of = 3.99×10−19 ? How do go about solving this? I multipled the constant...
Tuesday, December 11, 2012 at 4:04am

Chemistry
Consider the gold-platinum system which has a value of delta w of -4250 J/mole; (a) Calculate the enthalpy of mixing for a solution of 10% platinum and 90% gold. Express your answer in units of kJ/mole. (b) Is the dissolution of 10% platinum into gold an endothermic or an ...
Tuesday, December 11, 2012 at 3:45am

Chemistry
The fictitious compound, pandemonium carbonate Pn(CO3)2 hase a Ksp=3.091x10^-9M3 in water at room temperature. Calculate the solubility of Pn(CO3)2 in an aqueous solution of 1.11 M pandemonium sulfate Pn(SO4)2 (aq) . Express your answer in units of molarity.
Tuesday, December 11, 2012 at 3:44am

Chemistry
Answer the following questions by referring to the Cu-Al phase diagram shown below. (a) What is the lowest temperature at which a liquid can be found in a system of any composition of Cu-Al ? (b) A common alloy composition used in airplanes is 4 at. % Cu - 96 at. % Al. For ...
Tuesday, December 11, 2012 at 3:41am

Chemistry
The solubility of the fictitious compound, administratium fluoride ( AdF3 ) in water is 3.091x10^-4M . Calculate the value of the solubility product Ksp .
Tuesday, December 11, 2012 at 3:37am

Chemistry
(a) The phase diagram of the binary system, neodymium-scandium ( Nd-Sc ) is given below. There are two polymorphs in the solid state: alpha which is hexagonal close packed (HCP) and beta which is body-centered cubic (BCC). Identify all phases present at points 1, 2, and 3. ...
Tuesday, December 11, 2012 at 3:35am

Chemistry
Question One Lead chloride dissolves in water according to PbCl2(s)<-> Pb^2+ + 2Cl^- (aq) The solubility in pure water has been measured to be 4.44g . L^-1 . Calculate the solubility product of lead chloride in pure water. Your answer should be in units of molarity ...
Tuesday, December 11, 2012 at 3:30am

Chemistry
Question One The fictitious compound, pandemonium fluoride ( PnF2 ) has a Ksp value in water of 3.091x10^-9 M^3 at room temperature. Calculate the solubility of PnF2 in water. Express your answer in units of molarity. Question Two How would you expect the solubility of ...
Tuesday, December 11, 2012 at 3:24am

Chemistry
Question One: Comment on the solubility of hydrogen ( H2 ) in liquid ammonia ( NH3 ). State whether you expect hydrogen to be highly soluble or almost insoluble, and explain why. i)Highly soluble due to hydrogen bonding. ii)Highly soluble due to compatible nature of bonds. iii...
Tuesday, December 11, 2012 at 3:21am

Chemistry
Here is the phase diagram of water with attention given to phases at high pressure. Name all phases present at the markers 1, 2 and 3. Phases present at 1: Liquid I II III IV V VI VII VIII IX Phases present at 2: Liquid I II III IV V VI VII VIII IX Phases present at 3: Liquid ...
Tuesday, December 11, 2012 at 3:17am

chemistry
At a certain temperature, the Equilibrium constant, Kc, for this reaction is 53.3. At this temperature, 0.500 mol of H2 and 0.500 mol of I2 were placed in a 1.00-L container to react. What concentration of HI is present at Equilibrium? equation: H2 + I2 = 2HI
Tuesday, December 11, 2012 at 1:40am

Chemistry PLEASE HELP!!!
'A buffer is prepared by mixing a 100.omL of a 0.100 M NH3 solution with a 0.200M solution of NH4CL solution and making the total volume up to 1.000L of water. What is the volume of NH4Cl solution required to achieve a buffer at ph=9.5? Ka of NH4=5.6x10^-10. The textbook ...
Tuesday, December 11, 2012 at 12:14am

Chemistry
Hi, i'm really desperate! could anyone please help me with this question, I'm stumped. 'A buffer is prepared by mixing a 100.omL of a 0.100 M NH3 solution with a 0.200M solution of NH4CL solution and making the total volume up to 1.000L of water. What is the volume...
Tuesday, December 11, 2012 at 12:02am

Chemistry - Molarity
Potassium hydrogen phthalate is a monoprotic acid. Dihydrogen phthalate (H2C8H4O4) is a diprotic acid. An analyte sample contains 0.127 M KHP and 0.0678 M H2C8H4O4. What volume of a 0.205 M NaOH solution is required to neutralize 25.0 mL of the analyte solution? Molar masses: ...
Monday, December 10, 2012 at 10:56pm

Chemistry
please explain how % error and % yield would have effected the mass/moles of a substance in a reaction in a lab. In this case mass/moles of NaCl. NaHCO3+ HCl--> NaCl + CO2 + H2O
Monday, December 10, 2012 at 10:51pm

Chemistry 3A
C2H2(g)+ 5/2o2(g)-> 2Co2(g)+ H2o(g)+ 1255.8KJ how many grams of C2H2 are reacted when 310 KJ of heat are released? I left the oxygen (O) lowercase in the equation so it does not get mixed up with zero.
Monday, December 10, 2012 at 10:07pm

Chemistry 3A
CS2 + O2 -> CO2 + SO2 and 10.0 grams of each reactant, calculate the number of moles of SO2 that can be produced in this reaction
Monday, December 10, 2012 at 9:56pm

Chemistry 3A
compute the molarity of a solution consisting of 2.0 moles of calcium chloride in 500mL of solution.
Monday, December 10, 2012 at 9:42pm

Chemistry 3A
How many grams of KCl would you need to weigh out to prepare 0.25L of a 2.00 M KCl solution?
Monday, December 10, 2012 at 9:42pm

Chemistry 3A
calculate the mass of solid NaCl that must be added to 1.50L of a 0.100M AgNO3 solution to precipitate all the Ag+ ions in the form of AgCl. calculate the mass of AgCl formed.
Monday, December 10, 2012 at 9:39pm

chemistry
Assume that a particular reaction evolves 241 of heat and that 25 of work is gained by the system. What are the values of delta E and delta H for the system?
Monday, December 10, 2012 at 9:35pm

Chemistry
I have to sort compounds into groups, separating them by if they are acidic, Ionic, or Covalent. Heres the list: Calcium Carbonate Sodium Hypochlorite Sodium Chloride Sodium Hydrogen Carbonate Acetic Acid Ammonium Hydroxide Silicon dioxide Magnesium Sulfate Carbon Dioxide ...
Monday, December 10, 2012 at 9:21pm

chemistry urgent urgent
Analyze the properties of a sodium atom and a sodium ion. What are the differences in mass, stability, and reactivity that are caused due to the differences between the sodium atom and sodium ion?
Monday, December 10, 2012 at 9:00pm

chemistry
Acetyl chloride is a colorless, fuming liquid used primarily in the chemical industry. a)How is acetyl chloride produced? If 915 gallons is produced and shipped, will DOT require the carrier to display the FLAMMABLE placard? Explain your answer. b)When there is a bulk spill of...
Monday, December 10, 2012 at 8:31pm

Chemistry
How much heat (in kilojoules) is evolved or absorbed in the reaction of 3.35 of with enough carbon monoxide to produce iron metal?
Monday, December 10, 2012 at 8:17pm

chemistry
What volume in mL of 0.0985 M sodium hydroxide solution is required to reach the equivalence point in the complete titration of a 15 mL sample of 0.124 M phosphoric acid?
Monday, December 10, 2012 at 8:06pm

chemistry
how many moles of NaCl are in a box of salt containing 425g NaCl (g/mol)
Monday, December 10, 2012 at 7:47pm

chemistry
A scuba diver's tank contains 0.29kg of O2 compressed into a volume of 2.3L. Calculate the gas pressure at 8 degrees celcius.
Monday, December 10, 2012 at 7:15pm

Chemistry
A reverse osmosis unit is used to obtain drinkable water from a source that contains 0.530 g NaCl per liter. What is the minimum pressure (in torr) that must be applied across the semipermeable membrane to obtain water? Assume room temperature or about 298 K. (Don′t ...
Monday, December 10, 2012 at 7:09pm

Chemistry 3A
what is the maximum number of electrons that may occupy the second electron energy level?
Monday, December 10, 2012 at 6:59pm

Chemistry
A mixture of gases contains 2.00 mol of O2, 3.00 mol of N2, and 5.00 mol of He. The total pressure of the mixture is 850 torr. What is the partial pressure of each gas?
Monday, December 10, 2012 at 6:33pm

Chemistry
If the osmotic pressure of urea (CH4N20) in water is measured at 0.0259 atm at 25 degress C what is the molartiy of the urea solution?
Monday, December 10, 2012 at 6:11pm

Chemistry
if a student finds the molecular weight of an unknown liquid to be 115 g/mole and the molecular formula of the liquid is CHCl3, what is the percent error in the student's molecular weight?
Monday, December 10, 2012 at 6:06pm

Chemistry
How many moles of a gas fill a flask with a volume of 141 mL at 101 degrees Celsius and a pressure of 761 torr?
Monday, December 10, 2012 at 6:01pm

chemistry
determining the concentration of a strong acid HCl when your given that the volume is 10ml and the mass of NaOH is 0.10 and the volume is 13.45
Monday, December 10, 2012 at 5:54pm

chemistry
Please help. My teacher never went over crystal lattices and the book doesn't cover it either :( Copper crystallizes in a face-centered cubic lattice. If the edge of the unit cell is 351pm, what is the radius of the copper atom?
Monday, December 10, 2012 at 4:35pm

Chemistry 3A
what is the maximum number of electrons that may occupy the second electron energy level?
Monday, December 10, 2012 at 2:51pm

Chemistry 3A
calculate the empirical formula for an unknown compound from the following information: C= 39.2%, H= 8.73% and O= 52.1%
Monday, December 10, 2012 at 2:39pm

Chemistry 3A
how do i find the number of moles of oxygen atoms in: Al(OH)3
Monday, December 10, 2012 at 2:10pm

Chemistry 3A
how do we write a nuclear symbol?
Monday, December 10, 2012 at 1:32pm

chemistry
the oxidation number of Mn in MnO4- is +4 (true or false)
Monday, December 10, 2012 at 10:39am

chemistry
mixed about the 5grams of benzois acid and sugar. divide the mixture into two equal portions . to thheh first portion add 20ml of water. shake vigorously and filter. examine the residue and compare with the original sample. heat the filter to dryness and identify the residue. ...
Monday, December 10, 2012 at 10:33am

chemistry
a 2.55g sample of an unknown has a volume of 3.73 cm. what is the density of the unknown
Monday, December 10, 2012 at 10:24am

chemistry
#1 A pipet delivers 10.5, 10.3, 10.9 and 10.7 ml (a) find the mean volume and deviation from the mean for each and calculate the average deviation from the mean (b) calculate the relative deviation (in %) for this set of data. Relative deviation (%) = (average deviation from ...
Monday, December 10, 2012 at 10:05am

chemistry
#1 A pipet delivers 10.5, 10.3, 10.9 and 10.7 ml (a) find the mean volume and deviation from the mean for each and calculate the average deviation from the mean (b) calculate the relative deviation (in %) for this set of data. Relative deviation (%) = (average deviation from ...
Monday, December 10, 2012 at 10:05am

chemistry
a 2.55g sample of an unknown has a volume of 3.73 cm. what is the density of the unknown
Monday, December 10, 2012 at 10:01am

Chemistry
The fictitious compound, arrhenium fluoride (AhF), reacts with itself to form a dimer with the formula Ah2F2. The reaction is second order in AhF. The value of the rate constant is 8.591x10-3 M-1s-1. What is the initial rate of reaction in a reactor filled with AhF to a ...
Monday, December 10, 2012 at 1:31am

chemistry
what is the heat of vaporization if the vapor pressure of liquid water at 25 °C is 23.8 Torr and at a boiling point of 100 °C is 760 Torr.
Monday, December 10, 2012 at 1:16am

CHEMISTRY
if a pure liquid in a sealed container is in equilibrium with its own vapor, the dependence of the vapor pressure on the temperature and the heat of vaporization is governed by the Clausius-Clapeyron equation. what is the heat of vaporization if the vapor pressure of liquid ...
Monday, December 10, 2012 at 1:00am

Chemistry
The equation for photon energy, , is where = 6.626×10−34 (Planck's constant) and = 3.00×108 (the speed of light). What is the wavelength, , of a photon that has an energy of = 3.99×10−19 ? How do go about solving this? I multipled the constant...
Monday, December 10, 2012 at 12:18am

Chemistry
In the "Methode Champenoise," grape juice is fermented in a wine bottle to produce sparkling wine. The reaction is given below. C6H12O6(aq)--> 2 C2H5OH(aq) + 2 CO2(g) Fermentation of 746 mL grape juice (density = 1.0 g/cm3) is allowed to take place in a bottle ...
Sunday, December 9, 2012 at 11:36pm

chemistry
If you add 2 liters of .45% NaCl to 36 liters of blood that has a pH balance of 7.44, what will the new pH be?
Sunday, December 9, 2012 at 11:06pm

chemistry
If you add 2 liters of .45% NaCl to 36 liters of blood that has a pH balance of 7.44, what will the new pH be?
Sunday, December 9, 2012 at 10:57pm

chemistry
please explain How % errors would affected the mass/moles of substances in lab?
Sunday, December 9, 2012 at 10:16pm

chemistry
What volume in mL of 0.0985 M sodium hydroxide solution is required to reach the equivalence point in the complete titration of a 15 mL sample of 0.124 M phosphoric acid?
Sunday, December 9, 2012 at 9:39pm

General chemistry
The density of the vapor of a compound at 95 degrees C and 827 mmhg is 7.41 grams/liter. Calculate the molecular weight.
Sunday, December 9, 2012 at 6:49pm

chemistry
Steve, in an attempt to impress his girlfriend, plops 18.2 grams of sodium metal into 500 mL of concentrated phosphoric acid (density = 1.88 g/cm3) in a beaker. The reactants were both initially at 25 oC. The reaction gently produced bubbles of hydrogen and Janet was not ...
Sunday, December 9, 2012 at 6:24pm

Chemistry
The figure below is a heat curve for an unknown outerspace substance discovered by the Mars rover. By understanding the heat curve, scientists can make inferences about the composition of the planet. What is the temperature of fusion, Tfusion, and vaporization, Tvapor, for ...
Sunday, December 9, 2012 at 6:20pm

Chemistry
When 100 mL of Ba(NO3)2 solution at 25 degrees Celsius is mixed with 100 mL solution CaSO4 solution at 25 degrees Celsius in calorimeter, the white solid BaSO4 forms and the temperature of the mixture increases to 28.1 degrees Celsius. Assuming that the calorimeter absorbs ...
Sunday, December 9, 2012 at 6:11pm

Chemistry
Explain in step by step and provide calculations to show how you can prepare 1.50 L of 0.10 M H2SO4 solution starting with 16 M H2SO4
Sunday, December 9, 2012 at 6:06pm

Chemistry
What is true for water? A) In a phase diagram the solid-liquid coexistance line has a negative slope. B) In a phase diagram the solid-liquid coexistance line has a positive slope. C) The solid is more dense than the liquid. D) The solid is less dense than the liquid. E) The ...
Sunday, December 9, 2012 at 6:01pm

Chemistry
A compound of carbon, hydrogen, and oxygen was burned in oxygen, and 2.00g of the compound produced 2.868 g CO2 and 1.567 g H2O. In another experiment, 0.1107 g of the compound was dissolved in 25.0 g of water. This solution had a freezing point of -0.0894 degrees C. what is ...
Sunday, December 9, 2012 at 4:07pm

chemistry
How many gallons of C6H12 , measured at 20 degrees Celsius, must be burned to provide enough heat to warm 26.4m3 of water from 17.4 degrees Celsius to 32.8 degrees Celsious , assuming that all the heat of combustion is transferred to the water, which has a specific heat of 4....
Sunday, December 9, 2012 at 2:34pm

Chemistry
Fluorine reacts with oxygen to yield oxygen difluoride. 2 F2(g) + O2(g) 2 OF2(g)K = 2.00x 10^2 (a) Calculate [O2] at equilibrium when [OF2] = 0.25 mol/L and [F2] = 0.0208 mol/L. mol/L (b) Calculate [OF2] at equilibrium when [F2] = 0.088 mol/L and [O2] = 0.513 mol/L. mol/L
Sunday, December 9, 2012 at 2:12pm

Chemistry
Magnetite, an iron ore with formula Fe3O4, can be reduced by treatment with hydrogen to yield iron metal and water vapor. (a) Write the balanced equation. (Use the lowest possible coefficients.) 1Fe3O4(s) + 4H2(g)-> 3Fe(s) + 4H2O(g) (b) This process requires 36 kcal for ...
Sunday, December 9, 2012 at 2:10pm

Chemistry
Fluorine reacts with oxygen to yield oxygen difluoride. 2 F2(g) + O2(g) 2 OF2(g) What is the value of K if the following concentrations are found at equilibrium: [O2] = 0.200 mol/L, [F2] = 0.0100 mol/L, and [OF2] = 0.0633 mol/L
Sunday, December 9, 2012 at 2:07pm

Chemistry
The Ksp value for FeS is 6 x 10^-18 M. FeS(s) --> Fe^(2+)(aq) + S^(2-)(aq) What is DG at 25 degrees C for the reaction?
Sunday, December 9, 2012 at 2:06pm

Chemistry
Assume that 57.0 cal of heat is applied to a 28g sample of sulfur at 27 degrees C. What is the final temperature of the sample if the specific heat of sulfur is 0.175 cal/g degrees C?
Sunday, December 9, 2012 at 1:57pm

Chemistry
How much energy, in joules, must be absorbed to convert to Na+ all the atoms present in 1.00mg of gaseous Na? The first ionization energy of Na is 495.8 kJ/mol
Sunday, December 9, 2012 at 12:41pm

Chemistry
how to prepare 100cm3 of 1.0moldm3 copper sulphate and from this prepare 100cm3 of 0.1 moldm3 solution.similarly use the 0.1moldm3 to prepare a 0.05 moldm3 ,and the 0.05moldm3 solution to prepare 0.01 moldm3 and 0.001moldm3solution.
Sunday, December 9, 2012 at 12:37pm

Chemistry
At constant volume, the heat combustion of a particular compound is -3447.0 KJ/mol. When 1.205 g of this compound (molar mass = 119.94 g/mol) was burned in a bomb calorimeter, the temperature of the calorimeter (including its contents) rose by 5.007 degrees C. What is the heat...
Sunday, December 9, 2012 at 11:40am

Chemistry
Consider the molecular level representation of a gas There are: (a picture) 6 blue dots 5 orange dots 3 green dots (i think they are the diatomic one, because it is pairs) If the partial pressure of the diatomic gas is .750, what is the total temperature? I am totally lost, ...
Sunday, December 9, 2012 at 11:39am

Chemistry
If the heat from burning 6.000 g of C6H6 2C6H6(l) + 15O2(g) -> 12CO2(g) + 6H2O(l) + 6542 kJ is added to 5691 g of water at 21 °C, what is the final temperature of the water? Please tell me what I am doing wrong: 293,551= 5691*4.2*(Tf-21C) 293551= 23902.2Tf - 50946.2 ...
Sunday, December 9, 2012 at 11:34am

Chemistry
A certain compound containing only carbon and hydrogen was found to have a vapor density of 2.550 g/L at 100 degrees C and 760 mm Hg. If the empirical formula of this compound is CH, what is the molecular formula of this compound? I had some ideas as to how to solve this ...
Sunday, December 9, 2012 at 10:43am

Chemistry
How many moles of glucose , C6H12O6, can be "burned" biologically when 10.0 mol of oxygen is available. C6H12O6(s) + 602(g)---6CO2(g) + 6H2O(l)
Sunday, December 9, 2012 at 8:05am

chemistry
Calculate the number of moles of Al2O3 that are produced when 0.6 mol of Fe is produced in the following reaction. 2Al(s) + 3Fe(s)-- 3Fe(s) + Al2O3(s)
Sunday, December 9, 2012 at 8:01am

Chemistry
How many moles of aluminum are needed to react completely with 1.2 mol of FeO? 2Al(s) + 3FeO(s)-- 3Fe(s) + Al2O3(s)
Sunday, December 9, 2012 at 7:54am

Chemistry
How many moles of aluminum are needed to react completely with 1.2 mol of FeO? 2Al(s) + 3FeO(s)-- 3Fe(s) + Al2O3(s)
Sunday, December 9, 2012 at 7:53am

Chemistry
I need help with this problem A 0.75–L bottle is cleaned, dried, and closed in a room where the air is 22oC and 44% relative humidity (that is, the water vapour in the air is 0.44 of the equilibrium vapour pressure at 22oC). The bottle is brought outside and stored at 0....
Sunday, December 9, 2012 at 3:51am

chemistry
1)A solution has a [OH-] of 5.2 x 10-4. What is the [H3O+] in the solution? 2) A 0.25 M solution of a monoprotic acid, HA, has a pH of 2.54. What is Ka for this acid? The dissociation of HA is: HA + H2O <--> H3O+ + A- (Hint: write the expression for pH) 3 A solution has...
Sunday, December 9, 2012 at 3:17am

chemistry
A 0.200g sample containing mn02 was dissolved and analyzed by addiction of 50ml of 0.100M fe to drive the reation. The excess fe required 15ml of 0.0200 m kmn04. Find % mn304 fw 228.8mg/mmol in the sample? who helps me
Sunday, December 9, 2012 at 1:05am

Chemistry
At a local convenience store, you purchase a cup of coffee, but, at 98.4oC, it is too hot to drink. You add 23.0 g of ice that is –2.2oC to 248 mL of the coffee. What is the final temperature of the coffee? (Assume the heat capacity and density of the coffee are the same ...
Sunday, December 9, 2012 at 12:53am

Chemistry
A 0.75–L bottle is cleaned, dried, and closed in a room where the air is 22oC and 44% relative humidity (that is, the water vapour in the air is 0.44 of the equilibrium vapour pressure at 22oC). The bottle is brought outside and stored at 0.0oC. a) What mass of liquid ...
Sunday, December 9, 2012 at 12:51am

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