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December 7, 2016

Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

Chemistry
I have discovered a new chemical compound with the formula A2B. If a saturated solution of A2B has a concentration of 4.35x10-4M. a) What is the concentration of B2- ions? b. What is the concentration of A1+ ions? c. What is the solubility product constant for A2B? Can you ...
Sunday, March 16, 2014 by Serena

chemistry
Upon decomposition, one sample of magnesium fluoride produced 1.95 kg of magnesium and 3.05 kg of fluorine. A second sample produced 1.10 kg of magnesium.
Sunday, March 16, 2014 by elijah mann

Chemistry
What is the percent by volume concentration of a solution containing 300.mL of isopropyl alcohol and enough water to give 400.ml of solution?Which component is the solute and which is the solvent?
Sunday, March 16, 2014 by Hannah

Chemistry
What is the molarity of an aqueous solution that is 6.44% glucose (C6H12O6) by mass? (Assume a density of 1.03 g/mL for the solution.)
Sunday, March 16, 2014 by Shelby

Chemistry 151
5) How many mL of 1M HCl is used to make the following dilutions? a) 100mL of 0.1M HCl = b) 250mL of 0.5M HCl= c) 10ml of 0.01M HCl= 36.64 is the molar mass of hcl do I divide that into ml?
Sunday, March 16, 2014 by Selina

Chemistry
Find the molarity of 0.02g of silver nitrate dissolved in 1kg of water
Sunday, March 16, 2014 by Selina

Chemistry
2) Given the balanced reaction equation predict the moles of each product given the following reactants: AlCl3 + 3 NaHCO3 Al(OH)3 + 3 NaCl + 3 CO2 AlCl3 NaHCO3 Al(OH)3 NaCl 58.4 CO2 a 1 mol 1 mol ? ? b 1 mol 3 mol ? ? c 3 mol 1 mol ? ?
Sunday, March 16, 2014 by Selina

Chemistry
2 NaOH + CuSO4  Na2SO4 + Cu(OH)2 100g of Cu(OH)2 is needed. Assuming 100% yield, how much of 1M NaOH and 0.5M CuSO4 must be used in mL?
Sunday, March 16, 2014 by Selina

Chemistry
This is a problem I got on my Mastering Chemistry homework: Consider the following reaction: H2(g)+I2(g)⇌2HI(g) A reaction mixture at equilibrium at 175 K contains PH2=0.958atm, PI2=0.877atm, and PHI=0.020atm. A second reaction mixture, also at 175 K, contains PH2=PI2= 0...
Sunday, March 16, 2014 by Anna

chemistry
The specific heat of ethanol is 0.59 cal/g Celsius If one adds 450 cal of heat to 37 g of ethanol at 20 celsius what would the final temp be
Sunday, March 16, 2014 by Anonymous

Chemistry
The net reaction for fusion on a star like our Sun is: 4H(1,1) ==> He(4,2) + 2e(0,+1) Calculate the mass defect for this reaction. If one atom of He is formed this way, calculate the energy released. If one Kg of He is formed, calculate the energy released. The masses of ...
Sunday, March 16, 2014 by Jay

Chemistry
When the rate of the reaction 2NO+O2=2NO2 was studied, the rate was found to double when the O2 concentration alone was doubled but to quadruple when the NO concentration alone was doubled. Which of the following mechanisms accounts for these observations? a.) Step 1: NO + O2=...
Sunday, March 16, 2014 by Anonymous

Chemistry
Determine the rate constant for the following second-order reaction: A=C+2D given that the initial concentration of A is .3 M and that the concentration of C increase to .01 M in 200 seconds. Express the result in terms of the rate law for the loss of A.
Sunday, March 16, 2014 by Anonymous

chemistry
calculate the molarity of the solution prepared by dissolving 16.45g NH4NO3 in water to make 250.mL solution.
Sunday, March 16, 2014 by hunter

Chemistry
Alternative answers: A)10 B)13 C)1.9 D)3.8 E)12
Sunday, March 16, 2014 by Terry

Chemistry (titrations)
15.00 mL of 0.01200 M EDTA were used to titrate 50 mL aliquot solution containing iron (II). How much iron (II) is present in the solution? The answer in the book is 201 ppm. I tried getting the moles of EDTA (n,EDTA = 1.8 x 10^-4 mol). I think they're in 1:1 ratio, or I ...
Saturday, March 15, 2014 by Nina

Chemistry
Calculate the amount of energy released per gram of nuclei when 2 protium nuclei react to form deuterium nucleus (protium = 1.00782 amu, deuterium = 2.01410 amu). The answer in the book is -2.0 x 10^10 J, but I don't have any idea on how to do this. Please help, and thank ...
Saturday, March 15, 2014 by Nina

chemistry
Assuming that the volumes of carbon diox- ide and of propane are measured under the same experimental conditions, what volume of carbon dioxide is produced by the complete combustion of 20 L of propane? i just don't understand
Saturday, March 15, 2014 by whitney

chemistry
The distance versus time plot for a particular object shows a quadratic relationship. Which column of distance data is possible for this situation?
Saturday, March 15, 2014 by ry

chemistry
Calculate the pH for the hydrogen half-cell of the following voltaic cell if the observed cell voltage is 1.00 V. Mn|Mn2+(1.00 M)||H+(pH =?), H2(1.00 atm)|Pt
Saturday, March 15, 2014 by mary

chemistry
Determine the volume of 1.2 mol/L HCl that will be required to neutralize 150 mL of 0.080 mol/L Ba(OH)2
Saturday, March 15, 2014 by Esther

chemistry
3. a) Calculate the pH of the buffer solution prepared by mixing 40.0 mL of 0.100 M H3PO4 and 60.0 mL of 0.100 M KH2PO4. Given the pKa of H3PO4 is 2.12.
Saturday, March 15, 2014 by Syah

Science (Chemistry)
. Complete all the following for the reaction (NH4)2S + Cd(NO3)2 --> CdS(s) + NH4NO3 1. Balance this equation 2. Write the ionic equation 3. Write the net ionic equation
Friday, March 14, 2014 by Anonymous

Chemistry
I have to go to work this weekend so I'm trying to get my homework finished. Could you please help me figure out this question? Calculate the mass of 1.00 mol of each of these substances: a.) silicon dioxide (SiO2) b.) diatomic nitrogen (N2) c.) iron (|||) hydroxide (Fe(OH...
Friday, March 14, 2014 by Anonomous

chemistry 101
How many grams of bromine are in 1.57 grams of phosphorus tribromide?
Friday, March 14, 2014 by steve

Chemistry, please help!!!
I have to go to work this weekend so I'm trying to get my homework finished. Could you please help me figure out this question? Calculate the mass of 1.00 mol of each of these substances: a.) silicon dioxide (SiO2) b.) diatomic nitrogen (N2) c.) iron (|||) hydroxide (Fe(OH...
Friday, March 14, 2014 by Kelsi

Chemistry
Calculate the mass of 1.00 mol of each of these substances: a.) silicon dioxide (SiO2) b.) diatomic nitrogen (N2) c.) iron (|||) hydroxide (Fe(OH)3) d.) copper (Cu)
Friday, March 14, 2014 by Kelsi

Chemistry
When the rate of the reaction 2NO+O2=2NO2 was studied, the rate was found to double when the O2 concentration alone was doubled but to quadruple when the NO concentration alone was doubled. Which of the following mechanisms accounts for these observations? a.) Step 1: NO + O2=...
Friday, March 14, 2014 by Anonymous

Chemistry
In a bomb calorimeter, a 6.50 g sample of octane (C8H18) is combusted. The combustion enthalpy for octane is -5.45 MJ per mol C8H18. The temperature change of the calorimeter is 16.5 oC. What is the heat capacity of the calorimeter?
Friday, March 14, 2014 by Mary

Chemistry
Determine the rate constant for the following second-order reaction: A=C+2D given that the initial concentration of A is .3 M and that the concentration of C increase to .01 M in 200 seconds. Express the result in terms of the rate law for the loss of A.
Friday, March 14, 2014 by Anonymous

Chemistry
How much water can be produced from the complete reaction of 3.64 L of oxygen gas, at STP, with hydrogen gas? Answer in units of g
Friday, March 14, 2014 by Linda

Chemistry
Uranium 235 problem that exits
Friday, March 14, 2014 by HIna

Chemistry
how many grams of bromine will be present in a sample that molar mass of 70.0 g/mol and occupies a 2.00L container at 117 kPa and 35.1C
Friday, March 14, 2014 by Bernardo

Chemistry
A student has 600.0 mL of a 0.30M solution of HNO3. How much water must she add in order to make it a 0.15 M solution? Be careful how this question is answered.
Friday, March 14, 2014 by Katie

chemistry
Five liters of air at -50.0°C are warmed to 100.0°C. What is the new volume if the pressure remains constant?
Friday, March 14, 2014 by Anonymous

chemistry
In standardizing a potassium hydroxide solution, a student finds that 32.60mL of the base solution is needed to titrate 0.5045 grams of KHP to a phenolphthalein end point. In another titration, 26.63mL of this same base solution is needed to titrate 0.2003grams of an unknown ...
Friday, March 14, 2014 by Anonymous

chemistry
Calculate the molarity if a Ba(OH)2 solution if a 37.25ml portion of this solution is neutralized by 45.00mL of 1.500M HCl. You will need the balanced reaction
Friday, March 14, 2014 by Anonymous

chemistry
A radioactive sample contains 2.45 g of an isotope with a half-life of 3.8 days. How much of the isotope in grams will remain after 11.4 days?
Friday, March 14, 2014 by Jacques

Chemistry
How many grams of I2 are present in a solution if 39.85mL of 0.160M Na2S2O3 solution is needed to titrate the I2 Solution
Friday, March 14, 2014 by Jackie

Chemistry
How many grams of a 17.7% potassium sulfate solution would contain 419.9 g potassium sulfate? Answer in units of g
Thursday, March 13, 2014 by Kristen

Chemistry
Write the equation for the dissolution of NH4NO3 in water. If 5.95 mol of NH4NO3 are dissolved, how many total moles of ions are produced? Answer in units of mol
Thursday, March 13, 2014 by Kristen

Chemistry
How many moles of ammonia gas can be formed from the complete reaction of 44.8 liters of nitrogen gas at standard temperature and pressure (STP), according to the balanced equation, N2 (g) + 3H2 (g) arrow 2NH3 (g)?
Thursday, March 13, 2014 by Diana

Chemistry
Express the concentration of a commercial hydrogen peroxide solution, which is 3.0 (w/w), as a molarity. Show all work
Thursday, March 13, 2014 by Amber

chemistry
Can u show the solution to this problem? What is the mass of silver that can be prepared for 1.00g of copper metal Cu (s)+2AgNO3(ag)= Cu(NO3)2(ag)+2Ag(s)
Thursday, March 13, 2014 by vee

Chemistry
What are the molality and mole fraction of solute in a 32.3 percent by mass aqueous solution of methanol (CH3OH)? molality = ?m mole fraction =
Thursday, March 13, 2014 by Grace

Chemistry
What is the mole fraction of NaOH in an aqueous solution that contains 33.4% NaOH by mass?
Thursday, March 13, 2014 by Grace Badaki

Chemistry Help Please
1)how would the accuracy of your determined keq change if all your volume measurements were made with graduated cylinders rather than pipets ? 2) if all of the SCN^- was not converted completely to FeNCS^2+ when the calibration curve was prepared would this raise or lower the ...
Thursday, March 13, 2014 by Josh

Chemistry
The data below has been taken for the reaction of a dye with the hydroxide ion. The reaction was performed at two different hydroxide ion concentrations while the dye concentration was kept constant. What is the rate law? [OH─] = 0.10 M [OH─] = 0.20 M t (min) Abs ...
Thursday, March 13, 2014 by Nicole

CHEMISTRY.
what would be the VSEPR shape of pyridine?
Thursday, March 13, 2014 by Riana

chemistry
A student decomposes water to produce hydrogen and oxygen. If the student begins with 34.7 g of water and collects 24.9 g of oxygen, what is her percent yield?
Thursday, March 13, 2014 by Micky

Chemistry
I tried working this question out with the help already provided, but I couldn't ever get the right answer. If you could possibly explain how to do the problem step by step and include the right answer, I'd greatly appreciate it. Thanks! What mass of sodium benzoate ...
Thursday, March 13, 2014 by Madison

Chemistry
what is chemical equation for the preparation of siliconcarbide
Thursday, March 13, 2014 by Ashu

Chemistry
what is chemical for the preparation of siliconcarbide
Thursday, March 13, 2014 by Ashu

chemistry
if I have 1.60g of urea, how much water, in grams, should be added in the preparation of a 23.1 percent by mass solution?
Thursday, March 13, 2014 by Anonymous

chemistry
how many grams of sodium metal are needed to give 781 g of hydrogen?
Thursday, March 13, 2014 by nicole

Chemistry
The lattice enthalpies of NACL KCL and AGCL are 787,717 and 916 kj/mol; based on these values , arrange them in increasing order of water solubility and explain the answer.
Thursday, March 13, 2014 by Punk marley

Chemistry
The equilibrium constant Kc^i is 3.2x10^-34 at 25 degrees C for 2HCl(g) -> H2(g) + Cl2 (g). The equilibrium constant Kc^ii is .10 at 25 degrees C for 2ICl (g) -> Cl2 (g) + I2 (g). a) Calculate the equilibrium constant Kc for the reaction below at 25 C Cl2(g) + I2 (g) -&...
Thursday, March 13, 2014 by Lily

Chemistry 32
HCI (aq) is a strong acid. suppose you dissolved 0.0365 grams of HCI in water to give a final volume of 10.0 mL. what is the pH of this final solution. The molar mass of HCU is 36.5g /mole and the molar mass of water is 18.0g/mole
Wednesday, March 12, 2014 by jen

CHEMISTRY.
what would be the VSEPR shape of pyridine?
Wednesday, March 12, 2014 by Riana

chemistry
1. How many different 4p orbitals are there? 2. How many radial nodes are there? 3. How many angular nodes are there? (excluding the radial nodes) I thought it was 2,1, 2??
Wednesday, March 12, 2014 by abby

chemistry
1. it takes: ____ electrons to fill the 6d subshell of an atom. 2. It takes _____ electrons to fill the n=6 shell of an atom. I thought it was 22 and 72?
Wednesday, March 12, 2014 by abby

chemistry
What is the velocity, in meters per second, of a beam of electrons if they are to display a "de Broglie" wavelength of 41.2 um?
Wednesday, March 12, 2014 by abby

chemistry
What is the longest wavelength of light that can be emitted by a hydrogen atom that has an initial configuration of 8p^1? Thank you!!
Wednesday, March 12, 2014 by abby

chemistry
What is (delta E) for the traansition of an electron from n=9 to n=4 in a Bohr hydrogen atom? What is the frequency? Thank you!
Wednesday, March 12, 2014 by abby

chemistry
What is the wavelength, in nm, of light with an energy content of (1.35x10^3 kJ/mol)? Thank you!!!
Wednesday, March 12, 2014 by abby

chemistry
Arrange the three metals in order of their relative strengths as reducing agents, placing the strongest first. Write each metal as a half reaction.
Wednesday, March 12, 2014 by Brooke Deemer

chemistry
what is the chemical reactions for these... 2Na+2H2O->2NaOH+H2 2FeS2+3O2->Fe2O2+2SO2 CaCO3->CO2+CaO
Wednesday, March 12, 2014 by Sam

Chemistry
how do i name this chemical? S(ClO3)2
Wednesday, March 12, 2014 by Sam

Chemistry
how do i name this chemical? Fe(NO3)2
Wednesday, March 12, 2014 by Sam

Chemistry
If 6.51g of copper is reacted with 28.4g of silver nitrate, the products will be copper (II) nitrate and silver metal. What is the theoretical mass of silver that will be produced??
Wednesday, March 12, 2014 by juju

Chemistry
The reaction between 32.0g of CH4 and excess oxygen gas produces 75.9 of CO2 gas and some water. Determine the percent yield? Plss help :((
Wednesday, March 12, 2014 by juju

chemistry
Molality is a unit of concentration that measures the moles of solute per
Wednesday, March 12, 2014 by destiny

STATISTIC HELP
1.M&M candies are great for probability. The following tables are the color distributions for the candies. Fill in each table with the missing probability and answer the questions that follow. Plain Brown Blue Green Orange Red Yellow Probability 0.3 0.1 0.1 0.1 0.02 ??? ...
Wednesday, March 12, 2014 by bowershe

Chemistry
If you dilute 11.6 mL of a 3.5 M solution to make 214.8 mL of solution, what is the molarity of the dilute solution?
Wednesday, March 12, 2014 by Grace Badaki

Chemistry
What are the typical ppm values of hard water and an unknown water sample and how do their titrations compare?
Wednesday, March 12, 2014 by Jacob

Chemistry
How would applying an external pressure on the following equilibrium affects the distribution of iodide between the polar (aqueous) and non polar (varsol) phases? I2+I^- --> I3^- All are aqueous solutions
Wednesday, March 12, 2014 by Valamir

Chemistry
3. How does dissolved CO2 in distilled water affect the accuracy of the determination of a NaOH solution's concentration? The CO2 in the distilled water will create a more acidic solution which will affct the determination of NaOH solution's concentration? How is the ...
Tuesday, March 11, 2014 by Sandy

Chemistry
Determine the pH of a 1.2×10^−2 M solution
Tuesday, March 11, 2014 by Sara

Chemistry
What is the pH of a solution whose [H3O+] is 9.2× 10^−9 M?
Tuesday, March 11, 2014 by Sara

Chemistry Urgent
95.0mL of H2O is initially at room temperature (22.0∘C ). A chilled steel rod at 2.0∘C is placed in the water. If the final temperature of the system is 21.3∘C , what is the mass of the steel bar? Specific heat of water = 4.18 J/g⋅∘C Specific heat...
Tuesday, March 11, 2014 by Anna

Chemistry Urgent
A calorimeter contains 32.0mL of water at 13.0∘C . When 2.30g of X (a substance with a molar mass of 82.0g/mol is added, it dissolves via the reaction X(s)+H2O(l)¨X(aq) and the temperature of the solution increases to 30.0∘C . Calculate the enthalpy ...
Tuesday, March 11, 2014 by Anna

chemistry
95.0mLmL of H2O\rm H_2O is initially at room temperature (22.0∘C\rm{} ^{\circ}C). A chilled steel rod at 2.0∘C\rm ^{\circ}C is placed in the water. If the final temperature of the system is 21.3∘C^{\circ}C, what is the mass of the steel bar? Specific heat of ...
Tuesday, March 11, 2014 by Anna

Chemistry
A solution contains 0.00245 M HCl. Determine the [H3O+] for the solution. points Determine the [OH-]
Tuesday, March 11, 2014 by Sara

Chemistry
In neutralization reactions, acid + base ¨ salt + water HCl can be neutralized with NaOH. How many moles of NaOH will it take to neutralize 0.68 L of 0.29 M HCl? Is there a formula that I need to use here?
Tuesday, March 11, 2014 by Sara

chemistry
A solution prepared by mixing 16.7 mL of 0.760 M NaCl and 16.7 mL of 0.760 M KI was titrated with 0.380 M AgNO3 in a cell containing a silver indicator electrode and a saturated calomel reference electrode. (a) What is [Ag+] when 16.2 mL of 0.380 M AgNO3 have been added? ...
Tuesday, March 11, 2014 by Bobz

Chemistry
You have a vinegar solution you believe to be 0.8 M. You are going to titrate 21.39 mL of it with a NaOH solution that you know to be 0.774 M. At what volume of added NaOH solution would you expect to see an end point? Answer in units of mL
Tuesday, March 11, 2014 by Sara

Chemistry
At pH 3.85, which of the following is true? A.[lactic acid] > [lactate ion] B.[lactic acid] < [lactate ion] C.[lactic acid] = [lactate ion] At pH 11.61, which of the following is true? A.[lactic acid] = [lactate ion] B.[lactic acid] < [lactate ion] C.[lactic acid] &...
Tuesday, March 11, 2014 by chelsey

Chemistry
Sometimes the basicity of a solution is reported using pOH (pOH = -log[OH-]). What is the a. [OH-] if pOH = 1.90 b. [H3O+] if pOH = 12.94 c. pH if pOH = 9.70
Tuesday, March 11, 2014 by chelsey

Chemistry
Calculate the H3O+ concentration present in water under the following conditions. Enter your answer in scientific notation. [OH-] = 2.8 x 10-7 M [OH-] = 8.8 x 10-3 M [OH-] = 2.4 x 10-11 M
Tuesday, March 11, 2014 by Amber(:

chemistry
i need help with writing nomenclature for the formula and the compounds examples: Sodium bisulphate hydroiodic acid ammonium dihydrogen phosphate Zn(HCrO4)2 Calcium metal ferrous bromide sodium carbide phosphate radical liquid mercury plumbic oxide auric carbonite sodium ...
Tuesday, March 11, 2014 by Sam

Chemistry
A student walks at a brisk 3.50 mi/hr. Calculate the student's speed in yards/minute. I have 4 questions just like this one. Could you tell me step by step on how to do the double conversions? Thanks!
Tuesday, March 11, 2014 by Cheyenne

Chemistry check and help
what is ... Sodium bisulphate hydroiodic acid ammonium dihydrogen phosphate Zn(HCrO4)2 Calcium metal ferrous bromide sodium carbide phosphate radical Check... sodium bicarbonate NaHCO3
Tuesday, March 11, 2014 by Sam

Chemistry
A 247 lb fullback runs the 40 yd dash at a speed of 17.09 ± 0.1 mi/h. (a) What is his de Broglie wavelength (in meters)? (b) What is the uncertainty in his position? ** I found part A but I am unsure how to use this information to get part B. Any help is appreciated :)
Tuesday, March 11, 2014 by Amanda

Chemistry
A student walks at a brisk 3.50 mi/hr. Calculate the student's speed in yards/minute. I have 4 questions just like this one. Could you tell me step by step on how to do the double conversions? Thanks!
Tuesday, March 11, 2014 by Cheyenne

chemistry
cuso4.5h20 + 2c2h5no2 = cu(gly)2.h20 moles of cuso4.5h2o produced is 12mmoles moles of glycine poriduced is 16.5 mmoles. which is the limiting reagent?
Tuesday, March 11, 2014 by nera

chemistry
A 125.0 mg sample of an unknown, monoprotic acid was dissolved in 100.0 mL of distilled water and titrated with a 0.050 M solution of NaOH. The pH of the solution was monitored throughout the titration, and the following data were collected. Determine the Ka of the acid. ...
Tuesday, March 11, 2014 by Mohanad

Statistic Please Check
Check this out please Thanks Lesson 3 Unit 2 Probability Couplements, Disjoint Events and the addition Rule 1.M&M candies are great for probability. The following tables are the color distributions for the candies. Fill in each table with the missing probability and answer the...
Tuesday, March 11, 2014 by bowershe

chemistry
In the laboratory a student finds that it takes 20.7 Joules to increase the temperature of 11.0 grams of solid platinum from 20.5 to 35.8 degrees Celsius. What is the specific heat of platinum she has measured.
Tuesday, March 11, 2014 by grace

Chemistry
How do I balance the following reaction in acidic conditions? N2O4 + S8 = NO + H2SO3????
Tuesday, March 11, 2014 by Nicole

Chemistry: Freezing point depression
What is the free sing point of a solution of ethyl alchohol, that contains 24g of the solute (C2H5OH), dissolved in 780 g of water
Tuesday, March 11, 2014 by Matt

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