Jematormal91

Most popular questions and responses by Jematormal91
  1. Chemistry

    A solution contains 0.0200 M Pb2 (aq) and 0.0200 M Sr2 (aq). If we add SO42–(aq), what will be the concentration of Pb2 (aq) when SrSO4(s) begins to precipitate?

    asked on April 6, 2012
  2. Chemistry

    A solution contains 0.0500 M Ca2 (aq) and 0.0350 M Ag (aq). What will be the concentration of Ca2 (aq) when Ag2SO4(s) begins to precipitate? What percentage of the Ca2 (aq) can be separated from the Ag (aq) by selective precipitation? -Solving the 1st one

    asked on April 6, 2012
  3. Chemistry

    For the oxidation-reduction reaction equation given here, 2Rb+Br2 --> 2RbBr Indicate how many electrons are transferred in the formation of one formula unit of product.

    asked on May 11, 2012
  4. Chemistry

    Indicate how many stereoisomers are possible for each compound. b) tetrahedral [NiCl2Br2]2– c) octahedral [Fe(CO)4BrCl]

    asked on May 31, 2012
  5. Chemistry

    You need to prepare 100.0 mL of a pH=4.00 buffer solution using 0.100 M benzoic acid (pKa = 4.20) and 0.240 M sodium benzoate. How much of each solution should be mixed to prepare this buffer?

    asked on March 29, 2012
  6. Chemistry

    For the following battery: Cd(s) | CdCl2(aq) || Cl–(aq) | Cl2(l) | C(s) Write the reduction half reaction for the C(s) electrode.

    asked on May 11, 2012
  7. Chemistry

    Calculate the pH of a buffer solution obtained by dissolving 16.0 g of KH2PO4(s) and 27.0 g of Na2HPO4(s) in water and then diluting to 1.00 L. (pKa=7.21)

    asked on March 29, 2012
  8. CHEMISTRY

    a) Calculate the change in pH when 4.00 mL of 0.100 M HCl(aq) is added to 100.0 mL of a buffer solution that is 0.100 M in NH3(aq) and 0.100 M in NH4Cl(aq). b) Calculate the change in pH when 4.00 mL of 0.100 M NaOH(aq) is added to the original buffer

    asked on March 27, 2012
  9. Chemistry

    Why is AlCl3 an Arrhenius Acid, while BCl3 is not? How can I determine which is an Arrhenius Acid?

    asked on April 12, 2012
  10. Chemistry

    An experimental spacecraft consumes a special fuel at a rate of 2.10 × 102 L/min. The density of the fuel is 0.690 g/mL and the standard enthalpy of combustion of the fuel is –39.8 kJ/g. Calculate the maximum power (in units of kilowatts) that can be

    asked on April 21, 2012
  11. Chemistry

    Using Lewis Formulas, assign the oxidation states to the atoms in: (a) CH3S–SCH3(l) Assume sulfur is more electronegative than carbon.

    asked on May 10, 2012
  12. Chemistry

    Copper(I) ions in aqueous solution react with NH3(aq) according to: Cu+(aq) + 2NH3(aq) > Cu(NH3)2+ (aq) Kf=6.3x10^10 M^-2 Calculate the solubility (in g·L–1) of CuBr(s) in 0.65 M NH3(aq).

    asked on April 5, 2012
  13. Chemistry

    A solution of household bleach contains 5.25% sodium hypochlorite, NaOCl, by mass. Assuming that the density of bleach is the same as water, calculate the volume of household bleach that should be diluted with water to make 500.0 mL of a pH = 10.23

    asked on March 23, 2012
  14. Chemistry

    Carbon dioxide dissolves in water to form carbonic acid, which is primarily dissolved CO2. Dissolved CO2 satisfies the equilibrium equation. The acid dissociation constants listed in most standard reference texts for carbonic acid actually apply to

    asked on March 24, 2012
  15. Chemistry

    A geologist removes a sample of water from a lake in Nevada where the water level has been slowly dropping over time. The sample is found to be 0.02M in borax. The lake is circular in shape and is currently 500 meters in diameter and 50 meters deep. Using

    asked on April 30, 2012
  16. Chemistry

    Why can some borax also dissolve at room temperature?

    asked on April 30, 2012
  17. Chemistry

    For the oxidation-reduction reaction equation given here, 2Rb+Br2 --> 2RbBr Indicate how many electrons are transferred in the formation of one formula unit of product.

    asked on May 10, 2012
  18. Chemistry

    A d1 octahedral complex is found to absorb visible light, with the absorption maximum occcurring at 523 nm. a) Calculate the crystal-field splitting energy, Δ , in kJ/mol.

    asked on May 31, 2012
  19. Chemistry

    Above what Fe2 concentration will Fe(OH)2 precipitate from a buffer solution that has a pH of 8.03? The Ksp of Fe(OH)2 is 4.87×10-17 M3.

    asked on April 5, 2012
  20. Chemistry

    How much more acetic acid (pKa = 4.76) than acetate should be in solution to maintain a pH of 4.00?

    asked on March 29, 2012
  21. Chemistry

    Consider a process in which an ideal gas is compressed to one-sixth of its original volume at constant temperature. Calculate the entropy change per mole of gas. I know that the formula is chg.entropy= nRln(V2/V1), but how do I get the values for V2 and

    asked on April 27, 2012
  22. Chemistry

    A copper ore consists of 6.32% chalcopyrite, CuFeS2(s). How many metric tons of ore must be processed to obtain one metric ton of copper?

    asked on May 25, 2012
  23. CHEMISTRY

    Consider the following cell: Pt|H2(g, 0.130 atm)|H (aq, ? M)||Ag (aq, 1.00 M)|Ag(s) If the measured cell potential is 0.90 V at 25 °C and the standard reduction potential of the Ag /Ag half-reaction couple is 0.80 V, calculate the hydrogen ion

    asked on May 18, 2012
  24. Chemistry

    A copper ore consists of 6.32% chalcopyrite, CuFeS2(s). How many grams of ore must be processed to obtain one gram of copper?

    asked on May 25, 2012
  25. Chemistry

    Consider a process in which an ideal gas is compressed to one-sixth of its original volume at constant temperature. Calculate the entropy change per mole of gas.

    asked on April 27, 2012
  26. Chemistry

    Given that ΔGrxn>0, how do you explain that some of the borax actually dissolves at 25deg C?

    asked on April 30, 2012
  27. Chemistry

    Calculate the pH when 39.0mL of 0.321 of HA is mixed with 39.0mL of 0.321M NaOH where HA is a monoprotic weak acid with Ka= 7.5x10^-5 M ?

    asked on March 24, 2012
  1. Chemistry

    Thank you for your help!

    posted on April 6, 2012
  2. Chemistry

    I think I did it wrong... Ksp[Ag2SO4]= [SO42-][Ag+]^2 1.20x10^-5 = [SO42-][0.0350]^2 [SO42-}=9.80x10^-3M Then I substituted into: Ksp[CaSO4]= [SO42-][Ca2+] 4.93x10^-5 = [9.80x10^-3][Ca2+] [Ca2+]= 5.03x10^-3M

    posted on April 6, 2012
  3. Chemistry

    I'm actually not sure how to solve it, now I think the [Ca+]= 0.0500M

    posted on April 6, 2012
  4. Chemistry

    From my textbook, Ksp(Ag2SO4)= 1.20x10^-5 Ksp(CaSO4)= 4.93x10^-5

    posted on April 6, 2012
  5. Chemistry

    Thank you so much!

    posted on April 6, 2012
  6. Chemistry

    When I solve for b/a it equal 0.17, but I'm supposed to find how much more acetic acid should be in the solution.. How do I do that?

    posted on March 30, 2012
  7. CHEMISTRY

    I tried doing it and got for a) -0.03 and b) 0.03 but the program keeps telling me I have the wrong answers... I don't know what I am doing wrong.

    posted on March 27, 2012
  8. CHEMISTRY

    What gets substituted into the formula M1V1=M2V2? I don't understand...

    posted on March 23, 2012