Saturday
January 31, 2015

Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

Post a New Question | Current Questions

Chemistry
A reaction has a standard free-energy change of –12.40 kJ mol–1 (–2.964 kcal mol–1). Calculate the equilibrium constant for the reaction at 25 °C.
Sunday, November 25, 2012 at 8:04pm

Chemistry 1115
What is the chemical equation for the reaction that occurs when you add 0.1 M NaOH solution to the HC2H3O2-NaC2H3O2 buffer solution?
Sunday, November 25, 2012 at 8:03pm

Chemistry 1115
How do you calculate the molarities of HC2H3O2 and NaC2H3O2 in a buffer solution?
Sunday, November 25, 2012 at 8:00pm

chemistry
This soidum hydroxide solution was then used to determine the amount of acetic acid in vinegar. Three titrations of the sodium hydroxide solution against exactly 5mL of vinegar using phenolphthalein indicator required 22.85Ml, 22.67mL and 22.93mL of the sodium hydroxide ...
Sunday, November 25, 2012 at 7:48pm

Chemistry
The pressure exerted by a gas in a container depends on? and why?
Sunday, November 25, 2012 at 7:33pm

Chemistry
10. When a 5.00 mL sample of vinegar is titrated, 44.5 mLof 0.100 M NaOH solution is required to reach the end point. What is the concentration of vinegar in moles per liter of solution (molarity, M)?
Sunday, November 25, 2012 at 7:23pm

chemistry
Arrange the following oxides in order of increasing acidity: P2O5, As2O5, N2O5, SnO2, SeO3, and BaO. (Use the appropriate <, =, or > symbol to separate substances in the list.) I have no idea how to do this! please help!
Sunday, November 25, 2012 at 5:17pm

Chemistry
The hydronium ion concentration in coffee is 1 x 10^-5 M. What is the pH of coffee?
Sunday, November 25, 2012 at 3:51pm

Chemistry
The hydronium ion concentration for a solution is determined to be 4.5 x 10^-7 M. What is the concentration of the hydroxide ion? I just wanted to let the people that are being nice enough to help me know that this is for a study guide. It is not a test or quiz. :0) Thanks.
Sunday, November 25, 2012 at 3:37pm

chemistry
a sodium hydroxide solution was prepared according to the procedure outlined in this weeks experiment. This sodium hydroxide solution was standardized by by titration against exactly 10mL of a 0.28M hydrochloric acid solution. In three titrations, the volumes of the sodium ...
Sunday, November 25, 2012 at 3:26pm

chemistry
Write a balanced equation for the proton transfer reaction between water and phosphate ion. Determine in which direction the equilibrium is favored.
Sunday, November 25, 2012 at 2:54pm

Chemistry
When a 5.00 ml sample of vinegar is titrated, 44.5 ml of 0.100 m NAOH solution is required to reach the end point. What i sthe concentration of vinegar in moles per liter of solution?
Sunday, November 25, 2012 at 2:51pm

chemistry
sodium oxide reacts with carbon dioxide to form sodium carbonate. How much carbon dioxide is needed to produce 79g or sodium carbonate?
Sunday, November 25, 2012 at 2:22pm

Chemistry
How do you prepare 600.0mL of 0.48M Al(NO3)3*9H2O? Is this correct? 1. Measure out 71g of solution 2. Put approx. 300.0mL of water into container 3. Add the 71g of solution to the water and mix 4. Add more water until 600.0mL of solution is obtained 5. Mix •Chemistry - ...
Sunday, November 25, 2012 at 2:21pm

chemistry
How many moles of vanadium atoms, V, are needed to combine with 0.725 mol of O atoms to make vanadium pentoxide,V2O5?
Sunday, November 25, 2012 at 2:13pm

chemistry
To clean a clogged drain, 26g of sodium hydroxide is added to water to make 150ml of solution. What are the pH and pOH values for the solution?
Sunday, November 25, 2012 at 2:05pm

chemistry €
what is this? i cant find it in my book or online and yet its on my ICE chart and have to fill out.......
Sunday, November 25, 2012 at 1:59pm

chemistry- What does this symbol mean
if there is an E symbol with a slash through it on an ICE chart what does it stand for?
Sunday, November 25, 2012 at 1:06pm

chemistry- What does this symbol mean
if there is an E symbol with a slash through it on an ICE chart what does it stand for?
Sunday, November 25, 2012 at 1:00pm

chemistry
When aqueous solutions of iron (III) sulfate (Fe2(SO4)3) and sodkum hydroxide were mixed, a precipitate formed. What is the precipitate?
Sunday, November 25, 2012 at 12:50pm

chemistry
A 0.4671g sample containing sodium bicarbonate was titirated with hcl requiring 40.72ml. The acid was standardized by titrating 0.1876g of sodium carbonate FW 106mg/mmol requiring 37.86ml of the acid. Find the percentage of nahc03 fw 84mg/mmol in the sample. My own calculation...
Sunday, November 25, 2012 at 12:39pm

chemistry
A 93L sample of dry air is cooled from 145 to-22 under constant pressure.What is the final volume?
Sunday, November 25, 2012 at 10:54am

Chemistry 105
What is the weight/ weight% of a solution made by dissolving 12.0g of NaC1 in 100.0 g of water?
Sunday, November 25, 2012 at 2:17am

Chemistry 105
What is the molarity of a solution obtained by dissolving 10.35 g of KNO3 in some water and diluting to exactely 1 L in a graduated flask?
Sunday, November 25, 2012 at 2:13am

Chemistry
Complete and balance the following equations.Identify each type of the reactions. (a) Cr + O2 >Cr2O3: (b)Na2CO3 + Mg3(PO4)2: (c)H3BCO+ H2O> B(OH)3 + CO + H2:
Sunday, November 25, 2012 at 2:00am

chemistry
Represent this reaction with a balance chemical equation. Solid aluminium hydride is formed by a combination reaction of its two elements.
Sunday, November 25, 2012 at 1:53am

chemistry
We have not even covered this material. Samples of 131I take 10 hours to prepare to ship. It takes 2 weeks to get to its destination. How much 131I must be produced to ensure the patient receives 8 grams of NaI using the 131I isotope in the compound? Does this have to do with ...
Saturday, November 24, 2012 at 11:40pm

chemistry
How would you prepare a supersaturated solution of CuSo4 in 100ml of water
Saturday, November 24, 2012 at 10:10pm

Chemistry
Determine the percent by mass of water in your sample of hydrated copper (II) sulfate. Mass of water = 0.95 g Mass of anhydrous copper sulfate = 2.19 g Mass of hydrate copper sulfate = 3.14 g
Saturday, November 24, 2012 at 10:01pm

chemistry
3 Cl2 + 6 KOH go toKClO3 + 5 KCl + 3 H2O How many moles of potassium chlorate form when 2 moles of potassium hydroxide react completely?
Saturday, November 24, 2012 at 8:41pm

chemistry
solve the following and express your answer in scientific notation: (5.3 x 10^4) + (1.3 x 10^3) A. 5.4 X 10^4 B. 5.4 X 10^8 C. 6.6 X 10^7 D. 6.9 X 10^7 I say c
Saturday, November 24, 2012 at 8:02pm

chemistry
one isotope of chromium (atomic number 24) has an atomic mass of 53 amu. how many neutrons are in this particular isotope of chromium? A. 24 B. 29 C. 53 D. 77 I say A
Saturday, November 24, 2012 at 7:55pm

Chemistry
Calculate the mass percent of a solution containing 10.5 of and 91.5 of H2O.
Saturday, November 24, 2012 at 7:50pm

chemistry
compleat and balance this equation. Na2CO3+Mg3(PO4)2
Saturday, November 24, 2012 at 7:45pm

chemistry
If isomers of an alkane have the same molecular formula, how do they differ?
Saturday, November 24, 2012 at 7:31pm

chemistry
How does a complete structural formula differ from a condensed structural formula?
Saturday, November 24, 2012 at 7:31pm

Chemistry
How do you prepare 600.0mL of 0.48M Al(NO3)3*9H2O? Is this correct? 1. Measure out 71g of solution 2. Put approx. 300.0mL of water into container 3. Add the 71g of solution to the water and mix 4. Add more water until 600.0mL of solution is obtained 5. Mix
Saturday, November 24, 2012 at 7:30pm

chemistry
what is the molarity of the acid in when a 30mL sample of HCl is titrated with 10mL of 6M NaOH?
Saturday, November 24, 2012 at 6:47pm

chemistry
how does aluminum's position on the periodic table relate to its properties? i mean like how does it effect it's properties? thank you
Saturday, November 24, 2012 at 5:48pm

Chemistry
how do I determine the Ka for an acid HX if th epH of a 1.00M solution of HX is 4.5
Saturday, November 24, 2012 at 5:26pm

chemistry
Calculate the volume of gas you would expect to be evoleved if X mol of magnesium were reacted with an excess of HCl at standard conditions. Would the answer be X, 22.4X, or 22400X?
Saturday, November 24, 2012 at 5:12pm

chemistry
@20*C solubility - 22g CuSO4 / 100g H2O @40*C solubility - 42g CuSO4 / 100g H2O which is saturated and unsaturated a. @20*C is 6g CuSO4 / 25g H2O b. @20*C is 30g CuSO4 / 150g H2O c. @40*C is 99g CuSO4 / 250g H2O please show work thanks
Saturday, November 24, 2012 at 4:47pm

chemistry
Ca+NH3+Hcl will react to produce what?
Saturday, November 24, 2012 at 4:42pm

chemistry
This is an assesment question and im really bad at these, i did the first two questions and now i am stuck. They ask you to design a series of experiments that can be used to confirm the structure and organization of the table of relative strengths of acids and bases. the want...
Saturday, November 24, 2012 at 3:32pm

chemistry
At what temperature would you expect dinitrogen pentoxide to sublime? N2O5(s)-->N2O5(g) N2O5(s)= DELTA H -43.1 N2O5(s)= S (J*K1-*MOL1-)= 178.2 N2O5(g)= DELTA H 13.3 N2O5(g)= S (J*K1-*MOL1-)=355.7 where do i start here?
Saturday, November 24, 2012 at 2:51pm

chemistry
Balance this chemical equation. Cr2O7 2-(aq) + Cu(s)---> Cr3+(aq) +Cu2+aq) I don't understand how to do this problem. Where do i begin? thank you.
Saturday, November 24, 2012 at 2:46pm

chemistry
50 ml of Argon is collected at 60.0 degree C and 820.0 torr how much this sample weigh in grams?
Saturday, November 24, 2012 at 2:37pm

Chemistry
crystal structure of cesium chloride (CsCl). 1)Identify the crystal system: Cubic Tetragonal Orthorhombic Rhombohedral Hexagonal Monoclinic Triclinic 2)Identify the Bravais lattice: Simple cubic Body Centered Cubic Face Centered Cubic Hexagonal 3)Identify the basis of the ...
Saturday, November 24, 2012 at 12:44pm

Chemistry
Name the following crystallographic features below using proper crystallographic notation. Image One [2ˉ21] [1ˉ12ˉ] [1ˉ1(1/2)] [(1/2)(1/2ˉ)1ˉ] Image 2 (1ˉ02) (21ˉ0) (201) (1ˉ02ˉ) The wrong answer as far I known in Image One:[(1...
Saturday, November 24, 2012 at 4:18am

Chemistry
3C3H8 + 20H2CrO4-->9CO2 + 10 Cr2O3 + 32H2O What mass of chromium (III) oxide will be formed by complete reaction of 1.50g of propane with 35.0ml of 6.26M chromic acid?
Friday, November 23, 2012 at 11:26pm

Chemistry..
For the lewis structure of BCl3, does it have a total of 24 valence electrons? Also does it have a total of 4 bonds? If possible can you draw the lewis structure?
Friday, November 23, 2012 at 11:20pm

Chemistry
a stock solution of perchloric acid is 75.5% perchloric acid and has a density of 1.67g/ml. What is the molarity of the solution?
Friday, November 23, 2012 at 10:42pm

Chemistry
what is the name of the ions that are formed when the following compounds dissolve in water. (a) BaBr2 (b) (NH4)2CrO4 (c)HBr
Friday, November 23, 2012 at 10:16pm

Chemistry
A 0.02882 g sample of gas occupies 10.0-mL at 288.5 K and 1.10 atm. Upon further analysis, the compound is found to be 38.734% C and 61.266% F. What is the molecular formula of the compound? What is the geometry shape around each carbon atom? Polar or Nonpolar?
Friday, November 23, 2012 at 9:04pm

chemistry
amphetamine (c9h13n) is a powerful stimulant. what is the percent composition of all of the elements in this compound? A. 9%C;13%H;1%N B. 30%C;10%H;60%N C. 60%C;35$H;5%N D. 80%C;9.6%H;10.4%N I think b
Friday, November 23, 2012 at 8:51pm

chemistry
Predict how changes effects equilibrium for N2(g) + 3H2(g) -----> 2NH3(g) + heat a. add heat b. remove heat c. add NH3(g) d. remove NH3(g)
Friday, November 23, 2012 at 7:37pm

chemistry
what is the percent by mass of carbon in c3h8? A. 18.20% B. 20.0% C. 81.8% D. 85.0% I say A
Friday, November 23, 2012 at 7:35pm

chemistry
how many moles are in 243.6 g caco3? A.7.41 mol caco3 B 2.43 mol caco3 C.102.46 mol caco3 D.88.1 mol cao3 I say A
Friday, November 23, 2012 at 6:48pm

chemistry
a compound is found to be 94.1% o and 5.90% h. its molecular mass is 34.0. what is its molecular formula A. H3O2 B. OH C. H2O D. H2O2 I think D
Friday, November 23, 2012 at 6:41pm

chemistry
Calculate the amount of solute needed to make each of the solution. 225g of a 10% (m/m) K2CO3 solution .50kg of a 18% (m/m) KOH solution please show work thanks
Friday, November 23, 2012 at 4:18pm

Chemistry
If the initial volume is 500. ml at a temperature of 30 C, at a constant pressure, what would the new volume be if the temperature was changed to 50 C?
Friday, November 23, 2012 at 3:16pm

chemistry
A 0.682g sample of impure Na2hco3 yield a solid residue consisting of nahco3 and other solid a mass of 0.467g. What was the mass percent of nac03in sample. I do not understand I want you step by step. Clear explain for me. nahco3 = 84 n22hco3 = 106
Friday, November 23, 2012 at 3:12pm

chemistry
A 0.682g sample of impure NAHco3 yielded a solid residue consisting of NAc03 and other solid with a mass of 0.467g. What was the mass percent of NAc03 in the sample. The right 85.4% Who help
Friday, November 23, 2012 at 2:41pm

chemistry
How much NaOH (g) would you need to dissolve in water in order to prepare 2.75 L of a NaOH solution in which [OH-]= 0.50 M?
Friday, November 23, 2012 at 12:56pm

chemistry
what is the value of [OH-] in a 0.730 M solution of Sr(OH)2?
Friday, November 23, 2012 at 12:53pm

chemistry
The following soluble salts are strong electrolytes. For each, write a balanced equation for their dissociation in water. a. LiBr b. NaNO3 c. FeCl3 d. Mg(NO3)2
Friday, November 23, 2012 at 12:51pm

chemistry
What is the concentration of ammonia in a solution if 24.20 mL of a 0.1140 M solution of HCl are needed to titrate a 100.0 mL sample of the solution?
Friday, November 23, 2012 at 12:50pm

chemistry
Which material would you expect to have a greater bandgap energy between indium nitride (InN) and indium phosphide (InP)?
Friday, November 23, 2012 at 11:17am

Chemistry
1.a solution that is 6.5×10−2M in potassium propionate C_2 H_5 COOK or KC_3 H_5 O_2 and 8.5×10−2M in propionic acid C_2 H_5 COOH or HC_3 H_5 O_2 what is the ph? 2.a solution that is 8.0×10−2M in trimethylamine, CH_3 _3 N, and 0.10M in ...
Friday, November 23, 2012 at 12:57am

Chemistry
1.a solution that is 6.5×10−2M in potassium propionate C_2 H_5 COOK or KC_3 H_5 O_2 and 8.5×10−2M in propionic acid C_2 H_5 COOH or HC_3 H_5 O_2 what is the ph? 2.a solution that is 8.0×10−2M in trimethylamine, CH_3 _3 N, and 0.10M in ...
Thursday, November 22, 2012 at 11:41pm

Chemistry
You are asked to prepare a pH=4.00 buffer starting from 1.50 L of 0.0200 \; M solution of benzoic acid C_6 H_5COOH and an excess of sodium benzoate C_ H_5 COONa. How many grams of sodium benzoate should be added to prepare the buffer? Neglect the small volume change that ...
Thursday, November 22, 2012 at 11:36pm

chemistry
The pressure inside a hydrogen-filled container was 2.10 at 21 . What would the pressure be if the container was heated to 98 ?
Thursday, November 22, 2012 at 3:23pm

chemistry
A 0.46771g sample containing sodium bicarbonate was titrated with hcl requiring 40.72ml. The acid was standardized by titrating 0.1876g requiring 37.86ml of the acid.Find the percentage of NAHCo3 FW 84mg/mmoml in the sample? Who helps me to solve it
Thursday, November 22, 2012 at 1:10pm

chemistry
The volume at stp occuppied by a gas Q originally occupying 153.7dm at 287k and 750mm pressure (vapor pressure of gas Q at 287k is 12mm of Hg)
Thursday, November 22, 2012 at 12:45pm

chemistry
The volume at stp occuppied by a gas Q originally occupying 153.7dm at 287k and 750mm pressure (vapor pressure of gas Q at 287k is 12mm of Hg)
Thursday, November 22, 2012 at 12:44pm

chemistry
What percentage of the Ba2+ in solution is precipitated as BaCO3(s) if equal volumes of 2.4*10^-3 M Na2CO3(s) and 1.1*10^-3M BaCl2(aq) are mixed
Thursday, November 22, 2012 at 12:13pm

Chemistry
Your x-ray lab has a monochromator consisting of a single crystal of nickel cut so that the (001) plane lies in the cube face. At what angle (in degrees) should the cube face be tilted with respect to the incident beam in order to select radiation with a wavelength λ=3....
Thursday, November 22, 2012 at 8:34am

Chemistry
An x-ray generator operated at a plate voltage of 7000 V is incapable of producing Ni Kα radiation. Calculate the minimum energy required for a ballistic electron to produce Ni Kα radiation. Express your answer in units of eV.
Thursday, November 22, 2012 at 8:33am

Chemistry
CdO is cubic with a lattice constant a=4.695 A˚ and a density ρ of 8.15 g/cm3. Determine the crystal structure of CdO. Simple Cubic Face Centered Cubic Body Centered Cubic
Thursday, November 22, 2012 at 8:33am

Chemistry
a)Calculate the lattice constant a in palladium (Pd).express your answer in angstroms. b) Calculate the distance (in angstroms) between adjacent (110) planes in palladium (Pd). Hint: use your work from part (a).
Thursday, November 22, 2012 at 8:32am

chemistry
Calculate the normality of a 15% H2SO4 (MW=98g/n) solution. The density of the solution is 1.21 g/mL
Thursday, November 22, 2012 at 8:22am

chemistry
Calculate the density of atoms along [011] in molybdenum (Mo). Use only the information provided in your class Periodic Table, and express your answer in units of atoms/cm.
Thursday, November 22, 2012 at 7:41am

Chemistry
Your x-ray lab has a monochromator consisting of a single crystal of nickel cut so that the (001) plane lies in the cube face. At what angle (in degrees) should the cube face be tilted with respect to the incident beam in order to select radiation with a wavelength λ=3....
Thursday, November 22, 2012 at 4:34am

Chemistry
Name the following crystallographic features below using proper crystallographic notation. Image One [2ˉ21] [1ˉ12ˉ] [1ˉ1(1/2)] [(1/2)(1/2ˉ)1ˉ] Image 2 (1ˉ02) (21ˉ0) (201) (1ˉ02ˉ)
Thursday, November 22, 2012 at 4:34am

Chemistry
An x-ray generator operated at a plate voltage of 7000 V is incapable of producing Ni Kα radiation. Calculate the minimum energy required for a ballistic electron to produce Ni Kα radiation. Express your answer in units of eV.
Thursday, November 22, 2012 at 4:32am

Chemistry
CdO is cubic with a lattice constant a=4.695 A˚ and a density ρ of 8.15 g/cm3. Determine the crystal structure of CdO. Simple Cubic Face Centered Cubic Body Centered Cubic
Thursday, November 22, 2012 at 4:32am

Chemistry
Calculate the density of atoms along [011] in molybdenum (Mo). Use only the information provided in your class Periodic Table, and express your answer in units of atoms/cm.
Thursday, November 22, 2012 at 4:31am

Chemistry
(a) Calculate the lattice constant a in palladium (Pd). Use only the information available in the class Periodic Table, and express your answer in angstroms. (b) Calculate the distance (in angstroms) between adjacent (110) planes in palladium (Pd). Hint: use your work from ...
Thursday, November 22, 2012 at 4:30am

Chemistry
The crystal structure of cesium chloride (CsCl) is shown in the figure below. The dark spheres represent atoms of Cl. Identify the crystal system: Cubic Tetragonal Orthorhombic Rhombohedral Hexagonal Monoclinic Triclinic Identify the Bravais lattice: Simple cubic Body ...
Thursday, November 22, 2012 at 4:30am

chemistry
what is the boiling poinj of cs2,naf andco2
Thursday, November 22, 2012 at 12:20am

Chemistry
How much heat would be released by burning one gallon of octane? The density of octane is 0.703g/mL. 1 gallon= 3.79 liters.
Wednesday, November 21, 2012 at 11:03pm

chemistry
calculate Cu2+ in a 0.15M CuSO2 (aq) solution that is also 6.5M in free NH3. Cu^2+(aq)+ 4NH3(aq)<=> [Cu(NH3)4]^2+ kf=1.1*10^13
Wednesday, November 21, 2012 at 8:11pm

Chemistry
What is the pH at the equivalence point when 0.10 M HNO_3 is used to titrate a volume of solution containing 0.30 g of KOH?
Wednesday, November 21, 2012 at 8:02pm

chemistry
What percentage of the Ba2+ in solution is precipitated as BaCO3(s) if equal volumes of 2.4*10^-3 M Na2CO3(s) and 1.1*10^-3M BaCl2(aq) are mixed
Wednesday, November 21, 2012 at 7:36pm

Chemistry
A student measures k for a certain blue dye to be 19.4 M^-1 at 560 nm. What is the molarity of the dye in a solution with an absorbance of 0.118 at this wavelength?
Wednesday, November 21, 2012 at 6:18pm

Chemistry
How would a student make 500.0 mL of a 0.08500 M solution of iron(III) using a stock solution that is 0.3180 M in iron(III)? Explain how this would be done.
Wednesday, November 21, 2012 at 6:17pm

chemistry
what is the ionic equation for 2HNO3(aq)+Ba(OH)2(aq)
Wednesday, November 21, 2012 at 1:25pm

chemistry
A solution containing 80g of NaNO3 in 75g of H2O at 50 degrees celsius is cooled to 20 degrees celsius. A. how many grams of NaNO3 remain in solution at 20 degrees celsius? B. How many grams of solid in NaNO3 crystallized after cooling?
Wednesday, November 21, 2012 at 12:39pm

chemistry
Determine whether a solid forms when solutions containing the follow salts are mixed. If so, write the ionic equation and the net ionic equation. a: Na3PO4 and AgNO3 b: K2SO4 and Na2CO3 C: Pb(NO3)2 and Na2CO3 d: BaCl2 and KOH
Wednesday, November 21, 2012 at 11:33am

chemistry
What is the concentration of ammonia in a solution if 24.20 mL of a 0.1140 M solution of HCl are needed to titrate a 100.0 mL sample of the solution?
Wednesday, November 21, 2012 at 12:27am

Pages: <<Prev | 123 | 124 | 125 | 126 | 127 | 128 | 129 | 130 | 131 | 132 | 133 | 134 | 135 | 136 | 137 | Next>>

Post a New Question | Current Questions

Homework Help: Science

Members