Meenaakshi

Most popular questions and responses by Meenaakshi
  1. Chemistry

    Given acidity constant,Ka of benzoic acid is 6.28 X 10^-5. pH of 0.15 molar solution of this acid is ? Here is my method: Benzoic acid is a weak acid,hence it dissociates very little. So: C6H5COOH---> C6H5COO- + H+ [H+] and [C6H5COO-] are yet to be

    asked on March 23, 2012
  2. Chemistry

    For a system where: NH2OH + CH3NH3+ --> CH3NH2 + NH3OH+ 95% 95% 5% 5% State of equilibrium in the system is described by the percentages given above.Which of the species above is the strongest acid in the system? My answer is CH3NH3+, is it correct?

    asked on March 28, 2012
  3. Chemistry

    500.0mL of 0.220 mol/L HCl(aq) was added to a high quality insulated calorimeter containing 500.0mL of 0.200mol/L NaOH(aq).Both solutions had a density of 1.000g/mL & a specific heat of 4.184 J/g.K. The calorimeter had a heat capacity of 850.0 J/degree C.

    asked on March 23, 2012
  4. Chemistry

    500.0 mL of 0.220 mol/L HCl(aq) was added to a high quality insulated calorimeter containing 500.0mL of 0.200 mol/L NaOH(aq).Both solutions had a density of 1g/mL & a specific heat of 4.184 J/g.K.The calorimeter had a heat capacity of 850 J/C.Temperature

    asked on March 26, 2012
  5. Chemistry

    How many stereoisomers are there for 1,2-dichlorocyclopentane? The answer options are 1,2,3 & 4. I think it is 4 because there is one cis & one trans isomer,so when using the 2^n formula,the final answer is 2^2 =4.Is my approach correct? Need ur help

    asked on April 8, 2012
  6. Chemistry

    When pure sulfuric acid is dissolved in water,heat is evolved.To a calorimeter containing 300g of water at 20degree C,10.65g of sulfuric acid also added at the same temperature.The change in temperature,which was monitored by a digital probe with

    asked on March 22, 2012
  7. Chemistry

    Arrange these acids in terms of increasing acidity: CH3COOH, NH3+CH2COOH, CH3CONHCH2COOH Dr.Bob asked me what NH3+CH2COOH is.NH3+CH2COOH is obtained when 1 mol of glycine is added with a very strong acid,which results in both the amino & carboxyl groups to

    asked on April 10, 2012
  8. Math

    A saline solution is 20% salt. How many gallons of water must be added to dilute the mixture to 8 gals of a 15% saline solution? here is my method: using c1V1 = c2V2, (0.2)(V1) = (0.15)(8) V1 = 6 gals So, since 8 gals are required to dilute the saline

    asked on May 21, 2013
  9. Chemistry

    When solving Hess law problems,do we need to use all the equations given to get the Htotal or just choose the relevant equations that are related to the final equation required? Let's say there r 5 equations given,but the relevant equations are 3 only ,so

    asked on March 23, 2012
  10. Chemistry

    Dr.Bob, Arrange these acids in terms of increasing acidity: CH3COOH, NH3+CH2COOH, CH3CONHCH2COOH According to my Chem textbook,NH3+CH2COOH has a low pKa value since both the COOH & NH3+ are protonated,so it is most acidic. CH3COOH is a weak acid, but I'm

    asked on April 10, 2012
  11. Separation process

    Oil used to absorb benzene from gas is to be stripped with steam at P = 1atm to recover the benzene.Equlibrium at the operating temperature is approximated using Henry's Law.When the oil contains 10%mol of benzene,the oil's partial pressure is 5.07kPa.The

    asked on March 15, 2013
  12. Chemistry

    Hi Dr.Bob, Which is the correct formula for dinitrobis(ethylenediamine)cobalt(III) nitrate? I'm not sure which is the correct one out of these two: a)[Co(en)2(NO2)2]NO3 or b)[Co(NO2)2(en)2]3(NO3)3 ? At the instance, I've choosen option a). Is my naming

    asked on May 13, 2012
  13. Chemistry

    When 6200g of ethylene glycol and 16600g terephtalic acid reacted completely to generate poly(ethyleneterephtalate)(PET),how many grams of H20 generated? My working: mol of ethylene glycol = 6200g/(62g/mol) = 100 moles mol terephtalic acid =

    asked on April 25, 2012
  14. Chemistry

    Arrange these acids in terms of increasing acidity: CH3COOH, NH3+CH2COOH, CH3CONHCH2COOH My answer is CH3COOH,CH3CONHCH2COOH,NH3+CH2COOH . Is this correct Dr.Bob?

    asked on April 9, 2012
  15. Chemistry

    How many stereoisomers are possible for threonine?

    asked on April 9, 2012
  16. Chemistry

    Disulfide bonds in protein: a) results from an oxidation of thiol b)help to maintain the shape of proteins c)can be broken by reduction d)all of the above I know the option a) is correct,but I'm confused between options b)& c) as the informations on those

    asked on April 9, 2012
  17. Chemistry

    So,my second method is correct isn't it? The answer is -78.4kJ?

    asked on March 22, 2012
  18. Chemistry

    But in the answer options: a) -27.4 kJ b) -72.8 kJ c) -78.4 kJ d) -84.6kJ I attempted this problem in the other way.When using the q =mcdT,I added the mass of both water and sulfuric acid. q = (300g +10.65g)(4.184J/g.K)(6.55C) = 8513.43 J Then, I

    asked on March 22, 2012
  1. math

    Hi Teresa, Always remember: ln x = loge(log base e)x log x = log10(log base 10)x Example : ln x = 2 loge x = 2 x = e^2 log x = 5 log10 x =5 x = 10^5 (Hope this two examples have given you a rough understanding) ln(x-4) = -3 ln(x-4) = loge(x-4),right?

    posted on April 13, 2013
  2. calculus

    Hi sasha, Let me explain the methods step by step : a)3x^2 ln(2x) For this question, product rule must be applied : uv = udv/dx + vdu/dx where u = 3x^2 & v = ln(2x) Differentiate u, du/dx = 6x(I'm sure you know the basic differentiation) Differentiate v

    posted on April 13, 2013
  3. Math - Please help

    Hi Christopher, Let me explain the method of solving this problem: Given the area of the ring = 2123 ft^2 The formula for area is pi*r^2, where r is the radius Therefore,we need to find the r based on the area given 2123 ft^2 = pi*r^2 (work this out using

    posted on April 13, 2013
  4. Chemistry

    Thank you Dr.Bob & sorry for the inconvenience caused to you

    posted on April 10, 2012
  5. Chemistry

    Ok,that NH3+CH2COOH is obtained when 1 mol of glycine is added with a strong acid,which results in both amino & carboxyl groups to be fully protonated.

    posted on April 10, 2012
  6. Chemistry

    But Dr.Bob,from what I refer,NH3+CH2COOH is the strongest acid since it has both acid and NH3 protonated.Acetic acid is a weak acid,I'm not sure about the CH3CONHCH2COOH. That's what confuses me

    posted on April 10, 2012
  7. Chemistry

    Ok thank you Dr.Bob

    posted on April 9, 2012
  8. Chemistry

    Sorry what I meant was dividing the total heat with mole of NaOH ,not mass.

    posted on March 24, 2012
  9. Chemistry

    Ok,then how do I find the dH of NaOH? Do I need to use the total heat of the system and divide it by the mass of NaOH to get its dH ? I'm still confused Thank you

    posted on March 24, 2012
  10. Chemistry

    But in the answer options: a) -27.4 kJ b) -72.8 kJ c) -78.4 kJ d) -84.6kJ I attempted this problem in the other way.When using the q =mcdT,I added the mass of both water and sulfuric acid. q = (300g +10.65g)(4.184J/g.K)(6.55C) = 8513.43 J Then, I

    posted on March 22, 2012