Shweta Thakur posted an Question
June 30, 2020 ‚ÄĘ 12:40 pm 30 points
  • IIT JAM
  • Chemistry (CY)

Plz tell that for definition of enthalpy of neutralisation why can't we use i mole...as the actual definition is for 1 gram equivalentof acid and base

plz tell that for definition of enthalpy of neutralisation why can't we use I mole the actual definition is for 1 gram equivalent...

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    Priyanshu kumar

    https://www.aplustopper.com/enthalpy-heat-neutralization/ for very detailed information go through this link shweta

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    sir but all enthalpies like enthalpy of combu. ,enthalpy of formation , are defined for 1mole but how this definition valid if we say that for neutralisation 1mol of h2so4 we have to take 1mole of naoh

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    this is not a general definition for neutralisation( in terms of mole)

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    read my explanation shweta in the previous comment

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    ok sir

  • Suman Kumar Best Answer

    Hope this helps ūüôŹ

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    For HCl Gram equivalent=molar mass/ 1 as it's 1 mole will give 1 mole of H+

  • Suman Kumar

    It is defined as the energy released with the formation of 1 mole of water.

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    That's why we use equivalent.

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    For formation of water we need 1 mole of H+ & 1 mole of OH-.

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    For example 1 mole of H2SO4 release 2 mole of H+ so instead of mole we use gram equivalent.

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    So Gram equivalent= molar mass/2. That's why gram equivalent is useful.

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    Gram equivalent deals with no. of ions produced

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    so for this we can't used. definition in terms of mole right ??? because this vary for different acid and base example if we take1mol of h2so4 with 1 mol of naoh so its not a general definition that's why we use equivalent right

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    Absolutely Yes ūüėä

  • Suman Kumar best-answer

    The¬†enthalpy of neutralization¬†(őĒHn) is the change in¬†enthalpy¬†that occurs when one equivalent of an¬†acid¬†and one equivalent of a¬†base¬†undergo a¬†neutralization reaction¬†to form¬†water¬†and a¬†salt. It is a special case of the¬†enthalpy of reaction

  • comment-profile-img>
    Priyanshu kumar

    see the enthalpy of neutralisation say that 1 mole of acid or 1 mole equivalent is neutralised by 1 mole of base and vice versa....if there is strong acid and strong base same amount of heat is releesse that is -57.3 kj/mole

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    if you have problem in equivalent....see an equivalent is the number of moles of an ion in a solution multiplied by the valence of that ion. If 1 mol of NaCl and 1 mol of CaCl2 dissolve in a solution, there is 1 equiv Na, 2  equiv Ca, and 3 equiv Cl in that solution. (The valence of calcium is 2, so for that ion you have 1 mole and 2 equivalents.

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    also you find equivalent mass by (Molecular mass/ n- factor)...for acid n factor is basicity of that acid and if base then n factor is acidity of that base

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    read the above solution shweta you understand the concept behind this

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    as i have axplained above..see HCL have basicity of 1 as 1 H+ ions are produced and Basicity of H2So4 is 2 as 2 H+ ions are produced...so gram equiv of HCL = molar mass/1 and H2SO4 = Molar mass/2...similarly for base too...NAOH IS MONOACIDIC BASE, CA(OH)2 IS DIACIDIC BASE, AL(OH)3 IS TRIACIDIC BASE...so use n factor accordingly and get gram equiv

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    read shweta this explanation

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    ok

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    m asking about definition

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    yes as acid and base vary so gram equivalent weight here comes

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    yes sir

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    what is 1gram equivalent

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    now

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    when HCl acid is there then 1 grm equivalent = molar mass of HCL/1

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    when H2SO4 then Molar mass/2

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    i have explained this above

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    ok

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    sir

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