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February 7, 2016

Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

chemistry
A standard sodium carbonate solution is prepared in a 250 cm^3 volumetric flask during a titration,20 cm^3 of a 0,1 mol.dm^-3 nitric acid solution neutralises 25 cm^3 of the above standard solution according to the following balanced equation 2HNO3(aq) Na2CO3(aq)=>2NaNO3(aq...
Sunday, November 15, 2015 by alex

Chemistry
10000 tonnes of iron reacted in a blast furnace Fe2O3 calculate the typical mass of iron produced each day
Sunday, November 15, 2015 by Anonymous

Chemistry
A student performed an experiment to determine the molecular weight of a gaseous compound. Using the ideal gas law PV = nRT, and knowing the pressure, temperature, and volume of the vapor, the student calculated the number of moles of gas, n, to be 0.0443 mol. The weight of ...
Sunday, November 15, 2015 by Ericka

Chemistry
A 0.120 g sample of a diprotic acid of unknown molar mass is dissolved in water and titrated with 0.1218 M NaOH. The equivalence point is reached after adding 12.4 mL of base. What is the molar mass of the unknown acid?
Sunday, November 15, 2015 by Jorge

chemistry
Consider an atom traveling at 1% of the speed of light. The de Broglie wavelength is found to be 9.50 × 10–3 pm. Which element is this?
Saturday, November 14, 2015 by Anonymous

Chemistry
You have a 250ml solution of 0.13M calcium iodate. How many grams of potassium iodate need to be added to the solution to begin to precipitate calcium iodate? The solubility product constant for calcium iodate is6.47 *10^-6. B) you have a 250ml solution of 0.13 M calcium ...
Saturday, November 14, 2015 by Jack

Chemistry
Given the following half-reactions and their standard reduction potentials, Ni2+ + 2e− Ni E° = -0.25 V 2H+ + 2e− H2 E° = 0.00 V Ag+ + e− Ag E° = 0.80 V a spontaneous reaction will occur between: a. Ni2+ and H2 b. H+ and Ag c. Ag+ and Ni d. Ni2+ ...
Saturday, November 14, 2015 by Anonymous

Chemistry
What is the frequency of the photons emitted by hydrogen atoms when they undergo transition from n=4 to n=3?
Saturday, November 14, 2015 by Terrill

chemistry
draw a diagram showing the arrangement of the valency electrons in a molecule of the covalent compound arsine,ash3 use o to represent an electron from aresenic
Saturday, November 14, 2015 by ahmad

Chemistry
What is the minimum volume of 2.6 M HBr required to completely dissolve 35.0 g of potassium metal?
Saturday, November 14, 2015 by Jorge

chemistry
In many residential water systems, the aqueous Fe3+ concentration is high enough to stain sinks and turn drinking water light brown. The iron content is analyzed by first reducing the Fe3+ to Fe2+ and then titrating with MnO4- in acidic solution. Fe2+(aq) + MnO4-(aq) ? Mn2+(...
Saturday, November 14, 2015 by Dalton

chemistry
Calculate the volume occupied by 7g of nitrogen gas at 27 degree c and 750 mm of hg pressure
Saturday, November 14, 2015 by g srinivasa rao

Chemistry
When sodium chloride, NaCl, is added to water, it forms a solution. Rank the steps involved in the dissolution of salt in water from first step to last step. To rank items as equivalent, overlap them. a.) NaCl crystal is added to water b.) NaCl solution c.) The Na ions are ...
Saturday, November 14, 2015 by LuigiR

Chemistry
You have a large amount of 8.00 M stock solution. You need 1.60 L of 3.00 M solution for an experiment. How would you prepare the desired solution without wasting any stock solution? A.) Start with 1.60 L of water. Add stock solution until you reach a total volume of 2.56 L . ...
Saturday, November 14, 2015 by LuigiR

chemistry
calculate the pH of 5M aqueous ammonia. Given kb=1.8 x 10^-5
Saturday, November 14, 2015 by Nor Syafinas

Chemistry
2.1 g of a hydrocarbon fuel is burned in a calorimeter that contains 280 grams of water initially at 25.00◦C. After the combustion, the temperature is 26.55◦C. How much heat is evolved per gram of fuel burned? The heat capacity of the calorimeter (hardware only) is...
Friday, November 13, 2015 by Amy

Chemistry
A piece of metal of mass 25 g at 94◦C is placed in a calorimeter containing 57.4 g of water at 24◦C. The final temperature of the mixture is 34.2 ◦C. What is the specific heat capacity of the metal?Assume that there is no energy lost to the surroundings. ...
Friday, November 13, 2015 by Amy

Chemistry
Pyrites, FeS2, are a pollution-causing impurity in some coals. Upon combustion, the following rxn takes place: 2FeS2 + 5O2 à 4SO2 + 2FeO What volume of 6.0 M NaOH would be required to react with the SO2 produced from 1000 kg of coal containing 0.050% by mass of pyrite ...
Friday, November 13, 2015 by Mary White

Chemistry (Check)
6.3 mg of a boron hydride is contained in a flask of 385 mL at 25. degrees C and a pressure of 11 Torr. A. determine the molar mass of the hydride. B. which of the following hydrides is contained in the flask, BH3, B2H6, or B4H10 A. MM = 27.597 g/mol B. B2H6
Friday, November 13, 2015 by Anonymous

Chemistry
Calculate the density (g/L) of 478 mL of krypton at 47 degrees C and 671 mmHg. I wasn't sure about this one but I got: density = 2820 g/L with sig figs
Friday, November 13, 2015 by Anonymous

Chemistry (Check)
A sample of helium has a volume of 521 cc at a pressure of 75 cmHg and a temperature of 18 degrees C. When the temperature is increased to 23 degrees C, what is the volume of the helium? Vf = .530 L
Friday, November 13, 2015 by Anonymous

Chemistry (Check)
Calculate the mass of 15.0 L of NH3 at 27 degrees C and 900 mmHg. Mass of NH3 = 12.2 g
Friday, November 13, 2015 by Anonymous

Chemistry (Check)
A container holds 500. mL of CO2 at 20. degrees C and 742 Torr. What will be the volume of the CO2 if the pressure is increased to 795 Torr? Vf = .465 L
Friday, November 13, 2015 by Anonymous

Chemistry
Given 300.0 mL of a gas at 17.0 degrees C. What is its volume at 10.0 degrees C? Vf = .293 L
Friday, November 13, 2015 by Anonymous

Chemistry (Check)
A 30.0 L sample of nitrogen inside a rigid, metal container at 20.0 degrees C is placed inside an oven whose temperature is 50.0 degrees D. The pressure inside the container at 20.0 degrees C was at 3.00 atm. What is the pressure of the nitrogen after its temperature is ...
Friday, November 13, 2015 by Anonymous

Chemistry (Check)
Chlorine gas, Cl2, is widely used to purify municipal water supplies and treat swimming pool waters. If it occupies 23.5 cm^3 at STP, what volume will it occupy at -270. degrees C and a pressure of 1520 Torr? Vf = 1.29 x 10^-4
Friday, November 13, 2015 by Anonymous

Chemistry (Check)
A sample of gas has a volume of 12.0 L and a pressure of 20kPa. If the pressure of gas is increased to 50 psi, what is the new volume of the gas? Vf = 6.96 L
Friday, November 13, 2015 by Anonymous

Chemistry (Check)
How many molecules are there in 985 mL of nitrogen at 0.0 degrees C and 1.00x10^-6 mmHg? 3.50 molecules
Friday, November 13, 2015 by Anonymous

Chemistry (Check)
If a gas in a closed container is pressurized from 12 atm to 25 atm and tis original temperature was 32 degrees C, what would the final temperature of the gas be? Tf = 635 K
Friday, November 13, 2015 by Anonymous

Chemistry
An atom has a mass number of 39. If it has 20 neutrons, calculate its atomic number.
Friday, November 13, 2015 by Onyi

Chemistry-Dr.Bob
Calculate the mass of Fe(OH)3 s) produced by mixing 50.0 mL of 0.153 M KOH (aq) and 25.0 mL of 0.255 M Fe(NO3)3 (aq), and the number of moles of the excess reactant remaining in solution.
Friday, November 13, 2015 by Rucha

Chemistry
If the 50.00mL sample from problem 3 above was titrated with EDTA,what volume of a 0.00420 M EDTA solution would be needed to reach the endpoint? (Your answer should be given in milliliters.) (Problem 3 found that .0000625 moles of calcium carbonate were present in the sample)
Friday, November 13, 2015 by Alex

chemistry
Determine the pH of a 1 M aniline solution (Kb = 4.2 10-10). I am unsure how to start, any help?
Friday, November 13, 2015 by Logan

Chemistry
You have a large amount of 8.00 M stock solution. You need 1.60 L of 3.00 M solution for an experiment. How would you prepare the desired solution without wasting any stock solution?
Friday, November 13, 2015 by LuigiR

Chemistry
You have a large amount of 8.00 M stock solution. You need 1.60 L of 3.00 M solution for an experiment. How would you prepare the desired solution without wasting any stock solution?
Friday, November 13, 2015 by LuigiR

Chemistry
Show that the reaction caco3 ->cao+co2 is not a redox reaction
Friday, November 13, 2015 by Pooja

Chemistry
Show that the reaction caco3 ->cao+co2 is not a redox reaction
Friday, November 13, 2015 by Anonymous

Chemistry
Isomers are compounds that have the same number and kinds of atoms but have a different arrangement of the atoms. The enthalpies of atom combination for several pairs of gaseos isomers are given here. For each pair, decide which has the strongest bonds. a. CH3CH2CH2OH -4391....
Friday, November 13, 2015 by Sarah

Chemistry
Carbon disulfide (CS2) is useful, but flammable, solvent. Calculate DH for the following reaction. CS2(l) + 3O2(g) --> CO2(g) + 2SO2(g)
Friday, November 13, 2015 by Anonymous

chemistry
can some one help me with a few chem questions please. A chunk of iron weighs 4.32 g. a) How many iron atoms are there in this sample? 55.85 g Fe = 1.00 mol Fe = 6.022 x 1023 atoms Fe b) How many moles of iron are there in this sample? 2. . You have a copper bar weighing 71.24...
Thursday, November 12, 2015 by anna

Chemistry
Use the following data 2C(s) + 4H2(g) --> C3H8(g) DH= -103.85 kJ/molrxn C(s) + O2(g) --> CO2(g) DH= -393.51 kJ/molrxn H2(g) + 1/2O2(g) --> H2O(g) DH= -241.82 kJ/molrxn to calculate the heat of combustion of propane, C3H8 C3H8(g) + 5O2(g) --3CO2(g) + 4H20(g)
Thursday, November 12, 2015 by Anonymous

Chemistry
Predict the Order of increasing bond length for (i) H2(g) (ii) I2(g) (iii) F2(g) I don't know how I should know
Thursday, November 12, 2015 by Anonymous

chemistry
1. In the reaction 2Ca(s) + O2(g) → 2CaO(s), which species is oxidized?
Thursday, November 12, 2015 by anna

chemistry
1. How many grams of calcium chloride (CaCl2) are there in 600.0 mL of an aqueous solution that has a concentration of 0.450 M CaCl2? 2. The conjugate base of HS- is: 3. What mass of calcium chloride, CaCl2, is needed to prepare 3.65 L of a 1.75 M solution? The molar mass of ...
Thursday, November 12, 2015 by angel

Chemistry
Predict whether each of the following reactions would be exothermic or endothermic. a. CO(g) --> C(g) + O(g) b. 2H(g) + O(g) --> H20(g) c. Na+(g) + Cl-(g) --> NaCl(s) What is the sign of DH in each of these reactions? Please explain. I am very confused. Thanks
Thursday, November 12, 2015 by Anonymous

Chemistry
Predict whether each of the following reactions would be exothermic or endothermic. a. CO(g) --> C(g) + O(g) b. 2H(g) + O(g) --> H20(g) c. Na+(g) + Cl-(g) --> NaCl(s) What is the sign of DH in each of these reactions? Please explain. I am very confused. Thanks
Thursday, November 12, 2015 by Anonymous

Chemistry
Predict whether each of the following reactions would be exothermic or endothermic. a. CO(g) --> C(g) + O(g) b. 2H(g) + O(g) --> H20(g) c. Na+(g) + Cl-(g) --> NaCl(s) What is the sign of DH in each of these reactions? Please explain. I am very confused. Thanks
Thursday, November 12, 2015 by Anonymous

Chemistry
Silver oxide is used in small batteries called button batteries (Figure below). It decomposes upon heating to form silver metal and oxygen gas. 2Ag2O(s) → 4Ag(s) + O2(g) How many moles of silver are produced by the decomposition of 4.85 g of Ag2O?
Thursday, November 12, 2015 by Makayla Brad

Chemistry
Nitrogen and oxygen can react directly with one anotheer to produce nitrogen dioxide according to N2(g) + 2O2(g) --> 2NO2(g) The reaction may also be imagined to take place by first producing nitrogen oxide N2(g) + O2(g) --> 2NO(g) which then produces NO2 2NO(g) + O2(g...
Thursday, November 12, 2015 by Sarah

ics
Chemistry,what is the k.e of 4 moles of nitrogen gas at 127 degree centigrade?
Thursday, November 12, 2015 by usman

Chemistry (Check)
In a calorimeter experiment done at constant pressure in which all the heat from a chemical reaction was absorbed by the surrounding water bath, the temperature of the water went up by 2.31 K. If the size of the water bath was 200 g, what was the amount of heat transferred to ...
Thursday, November 12, 2015 by Anonymous

Chemistry
How many moles of gas must be forced into a 4.4 L tire to give it a gauge pressure of 32.4 psi at 30 ∘C? The gauge pressure is relative to atmospheric pressure. Assume that atmospheric pressure is 14.5 psi so that the total pressure in the tire is 46.9 psi .
Thursday, November 12, 2015 by Staci

Chemistry
Oxyacetylene torches are fueled by the combustion of acetylene, C2H2. 2C2H2(g) + 5O2(g) --> 4 CO2(g) + 2H2O(g) If the enthalpy change for the reaction is -2511.14 kJ/molrxn, how much heat can be produced by the reaction of a. 2mol of C2H2? b. 1 mol of C2H2? c. .500 mol of ...
Thursday, November 12, 2015 by Sarah

Chemistry Lab Work Help!
We used a buret today, and I don't get how to calculate volume. I have an initial reading of 49.97 and a final buret reading of 30.49. How do I get the volume? I thought I just subtracted the final from the initial, but someone said their tutor told them to take 50-their ...
Thursday, November 12, 2015 by Anonymous

Chemistry
The reaction between hydrogen and oxygen to produce water gives off heat. What is the source of this heat? how could this heat be measure?
Thursday, November 12, 2015 by Anonymous

Chemistry
On Earth, naturally occurring calcium metal contains 6 isotopes: Ca-40, Ca-42, Ca-43, Ca-44, Ca-46, Ca-48. Select all of the following that are true for a sample of naturally occurring calcium. A) The average mass of the calcium atoms is 40.078 amu. B)One mole of Ca-40 has a ...
Thursday, November 12, 2015 by Kayte

chemistry
Which is the molecular formula of a compound with the empirical formula BCH3 and a molecular mass of 103.38g/mole?
Thursday, November 12, 2015 by Taylee

Chemistry
If I have 4.53*10^-15 moles of tantalum atoms, how many tantalum atoms do I have?
Thursday, November 12, 2015 by Tay

Chemistry - Energy: Phase Changes
An ice cube at 0 degrees Celsius is placed in a pouch and dropped into 30.0g of water in a cup at 45 degrees Celsius. The ice cube melts and the resulting water warms up. The lowest temperature reached by the 30.0g of water in the cup was 20.0 degrees Celsius. What was the ...
Thursday, November 12, 2015 by Kid

Chemistry - Energy: Phase Changes
If 13.4 kJ of energy are added to 1.00 kg of ice at 0 degrees Celsius, how much water at 0 degrees Celsius is produced? How much ice is left? The molar heat of melting is 6.01 kJ/mol. So... 6.01 kJ -> 1 mol (6.01 kJ of energy can melt 1 mole of ice) Then... 13.4 kJ -> x...
Thursday, November 12, 2015 by Kid

Chemistry
Assign oxidation numbers for the following chemical equation: 2Al + 3H2SO4 ---> Al2(SO4)3 +3 H2 What was oxidized? What was reduced? My answer: Oxidation numbers going from the left side of the chemical eq to the right side.. Al: 0 H: +1 S: +6 O : -2 Al: +3 S: +6 O: -2 H: 1...
Thursday, November 12, 2015 by Rucha

institute of health sciences
Chemistry A) determine the mass of sodium hydroxide needed to prepare 100ml of 0.5M standard solution B) describe the procedure used to prepare the standard solution C) use the 100ml stock solution of 0.5M sodium hydroxide to neutralize H2SO4 by volumetric analysis I) ...
Thursday, November 12, 2015 by trendy

Chemistry
Which is easier to remove an electron from, N or O? Why? Is it O? Which is easier to remove an electron from, B or Be? Why? Is it B?
Thursday, November 12, 2015 by Rucha

Chemistry
How man kilojoules of energy are needed to vaporize a 28.6g sample of liquid benzene at its normal boiling point of 80C?
Thursday, November 12, 2015 by Judy

Chemistry
Which element's 4+ ion would have the following electron configuration? [Kr]4d^10
Thursday, November 12, 2015 by Rucha

Chemistry
Nitrogen dioxide is one of the components of photochemical smog. a.The energy required to split NO and O from NO2 is 305 KJ/mol. If there are 6.02E23 particles/mol, what is the energy required to do this? (I got 5.07E24) b. What is the maximum wave length of radiation that ...
Thursday, November 12, 2015 by Brooke N

Chemistry-Dr.Bob
What is the effective nuclear charge of the following? F- Na+ I know that for F- it is 9-7=2 and for Na+ it is 11-2=9, but what about the charges?? I don't understand what effect do the charges make? If 9-7 then isn't it just simply F and not F-? Similarly, if 11-2 ...
Thursday, November 12, 2015 by Rucha

chemistry
can anyone help with this problem please..... Potassium chlorate decomposes according to the following equation: 2KClO3 (s) → 2KCl (s) + 3O2 (g). If a 3.00 g sample of KClO3 is decomposed and the oxygen is collected at 24.0 °C and 0.991 atm, what volume of oxygen gas...
Thursday, November 12, 2015 by angel

chemistry
How many atoms are in a drop of mercury that has a diameter of 1.0 mm? (Volume of a sphere is 4ðr3/3; density of mercury = 13.6 g/cm3)
Thursday, November 12, 2015 by temi

chemistry
What is the pH of a buffer solution that has CH3CO2H=0.68 M and CH3CO2- =0.58 M, and has 0.01 M concentration of H2SO4 added to it? Ka of acetic acid is 1.8x10-5
Wednesday, November 11, 2015 by Randy

chemistry
The solubility of Na3(PO4) is 0.025 M. What is the Ksp of sodium phosphate?
Wednesday, November 11, 2015 by Randy

chemistry
What is the pH of a 0.5 M solution of NaHCO3? Kb = 2.4x10-8 (base)
Wednesday, November 11, 2015 by Randy

chemistry
what is the minimum frequency that will produce the photoelectric effect for rubidium(Rb)? (if it matters the frequency=5.2E24Hz or greater and I'm solving for the binding energy)
Wednesday, November 11, 2015 by Brooke N

chemistry
What is the wavelength, frequency, temperature, and type of the electromagnetic radiation that has: a. 90% the speed of light b. 50% the speed of light c. 10% the speed of light d. 5% the speed of light e. 1% the speed of light
Wednesday, November 11, 2015 by Brooke N

chemistry
The De Broglie wavelength of electrons used in an experiment utilizing an electron microscope is 96.00pm. what is the speed of one of these electrons? (De Broglie's equation is wavelength=6.63E-34 / (mass*velocity))
Wednesday, November 11, 2015 by Brooke N

Chemistry-Dr.Bob
Use Coulomb's law to calculate the ionization energy in kJ/mol of an atom composed of a proton and an electron separated by 176.00 pm .
Wednesday, November 11, 2015 by Rucha

Chemistry
Why are the two words "alkaline" and "earth" used to name the group 2 metals?
Wednesday, November 11, 2015 by Sarah

chemistry or physics
What is the speed of light in scientific notation?
Wednesday, November 11, 2015 by Brooke N

chemistry
how can you test to see if a light with wavelength 413nm is the same light with a frequency of 6.26*10^14Hz?
Wednesday, November 11, 2015 by Brooke N

chemistry
Determine the number of photons: A certain photon detector receives a signal of total energy 4.05*10^18 Joules from radiation of wavelength 535.00nm. (The only equation I can think to use is E(energy)= 6.63*10^-34 * (C(speed of light) / wavelength, but after I solve for speed ...
Wednesday, November 11, 2015 by Brooke N

Chemistry
You are given a solution of HCOOH (formic acid) with an approximate concentration of 0.20 M and you will titrate with a 0.1105 M NaOH. If you add 20.00 mL of HCCOOH to the beaker before titrating, approximately what volume of NaOH will be required to reach the end point?
Wednesday, November 11, 2015 by Amber

Chemistry- Dr. Bob
Use Coulomb's law to calculate the ionization energy in kJ/mol of an atom composed of a proton and an electron separated by 176.00 pm .
Wednesday, November 11, 2015 by Rucha

top ville college
Chemistry What volume of carbon (iv) oxide at s.t.p is evolved when o.5moles of NaHCO3 is heated
Wednesday, November 11, 2015 by olamide

chemistry
1. Calcuate the distance(km) from the Earth to the Moon if it takes light 1.3 seconds to make the trip? 2. Saturn is about 1.2 billionkm from Earth. How long does it take light to travel that distance? (I was only given the wave equation, Max Plancks equation, De Broglies ...
Wednesday, November 11, 2015 by Brooke N

chemistry
Balance the following redox equation. hno2(aq) + h2so4(aq) + k2cr2o7(aq)= hno3(aq) + cr2(so4)3 + h20 + k2s04?
Wednesday, November 11, 2015 by muzo

chemistry
balance the following redox equation. hno2(aq) + h2so4(aq) + k2cr2o7(aq)= hno3(aq) + cr2(so4)3 + h20 + k2s04
Wednesday, November 11, 2015 by muzo

Chemistry- Dr. Bob
Why doesn't Rb react with N2?
Wednesday, November 11, 2015 by Anonymous

Organic Chemistry
A sample of carvone was found to be 39% optically pure in favor of the dextrorotatory enantiomer. The specific rotation for enantiomerically pure carvone is 61o. The polarimetry experiment that led to this result was performed utilizing a 2.5 dm polarimeter tube and a solution...
Wednesday, November 11, 2015 by polly

chemistry
how do you go about to find the grams that will react with 90g acetic acid
Wednesday, November 11, 2015 by neliswa

Chemistry
What volume of 18N H2SO4 is required to prepare 125 ml of 6.0 N H2SO4?
Wednesday, November 11, 2015 by Momo

chemistry
A viral preparation was inactivated in a chemical bath. The activation process was found to be first order in virus concentration. The beginning of the experiment 2% of the virus was found to be inactivated per minute. [i] Evaluate k for the inactivation process in units (1/s...
Wednesday, November 11, 2015 by Steven

Chemistry
To determine the calories of a food, the energy released is calculated based on the mass used in the calorimeter. If a 0.8 g nut is consumed in a bomb calorimeter and the resultant temperature change is 80.3 degrees C for 50 mL of water, what would be the energy in Calories ...
Tuesday, November 10, 2015 by Anonymous

Chemistry
Two electrolysis cells are set up in series so that the same current flows through each. In one compartment 5.40 g of Ag (molar mass = 108 g/mol) is deposited from a Ag+ solution. What mass of Cu (molar mass = 64 g/mol) is deposited simultaneously if the other cell contains ...
Tuesday, November 10, 2015 by Anonymous

Chemistry
Styrene is produced by catalytic dehydrogenation of ethyl- benzene at high temperature in the presence of superheated steam. Given the following data, Ethylbenzene, C6H5--CH2CH3 : delta Ht = -12.5 kJ/mol, delta Gt = 119.7 kJ/mol and S = 255 J/mol*K Styrene, C6H5--CH==CH2 : ...
Tuesday, November 10, 2015 by Judith

Chemistry
How do I find the number of moles of NaOH when given 2M and 50.0mL? Also with HCl?
Tuesday, November 10, 2015 by Anonymous

CHEMISTRY!!!!!!!!!!
Styrene is produced by catalytic dehydrogenation of ethyl- benzene at high temperature in the presence of superheated steam. Given the following data, Ethylbenzene, C6H5--CH2CH3 : delta Ht = -12.5 kJ/mol, delta Gt = 119.7 kJ/mol and S = 255 J/mol*K Styrene, C6H5--CH==CH2 : ...
Tuesday, November 10, 2015 by Judith

chemistry
find the percentage by mass of nitrogen present in (NH4)2SO4
Tuesday, November 10, 2015 by lucky

Chemistry
The molar mass of the reagent, Fe(NH4)2(SO4)2.6H2O is 392.14 g/mol. Now suppose the measured mass of Fe(NH4)2(SO4)2.6H2O during the practical was 0.0218 g and this was dissolved in 50ml of deionized water that contains 1 to 2ml of concentrated sulphuric acid and transfer ...
Tuesday, November 10, 2015 by Mara

Chemistry
Question Given the equation: 4 Fe(s) + 3 O2(g) ? 2 Fe2O3(s), what is the theoretical yield of Fe2O3 from the reaction of 4.86 g Fe with excess O2? b. If 6.76 g Fe2O3 are actually obtained from 4.86 g Fe, what is the percent yield? c. Under other conditions, the percent yield ...
Tuesday, November 10, 2015 by Kami

chemistry
Calculate the molar enthalpy change for this reaction: HCl(aq 1.00M) + NaOH -> NaCl(aq,.500M)+ H2O Initial temp: 22.15 degrees Celsius Extrapolated temp: 25.87 degrees Celsius DT: 3.72 degrees Celsius Notes: Calculate the enthalpy change for this reaction. The density of ....
Tuesday, November 10, 2015 by Failure

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