मराठी
कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

Λ⁢0𝑚⁢(NH⁢4⁢OH) is equal to ______.

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प्रश्न

\[\ce{\Lambda^0_m(NH4OH)}\] is equal to ______.

पर्याय

  • \[\ce{\Lambda^0_m(NH4OH) + \Lambda^0_m(NH4Cl) - \Lambda^0(HCl)}\]

  • \[\ce{\Lambda^0_m(NH4Cl) + \Lambda^0_m(NaOH) - \Lambda^0(NaCl)}\]

  • \[\ce{\Lambda^0_m(NH4Cl) + \Lambda^0_m(NaCl) - \Lambda^0(NaOH)}\]

  • \[\ce{\Lambda^0_m(NaOH) + \Lambda^0_m(NaCl) - \Lambda^0(NH4Cl)}\]

MCQ
रिकाम्या जागा भरा
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उत्तर

\[\ce{\Lambda^0_m(NH4OH)}\] is equal to \[\ce{\mathbf{\underline{\Lambda^0_m(NH4Cl) + \Lambda^0_m(NaOH) - \Lambda^0_m(NaCl)}}}\]

Explanation:

(i) \[\ce{NH4Cl <=> NH^{+}4 + Cl-}\]  

(ii) \[\ce{NaCl <=> Na+ + Cl-}\]  

(iii) \[\ce{NaOH <=> Na+ + OH-}\]   

(iv) \[\ce{NH4OH <=> NH^{+}4 + OH-}\] 

To get equation (iv),

\[\ce{\Lambda^0_m(NH4Cl) + \Lambda^0_m(NaOH) - \Lambda^0(NaCl) = \Lambda^0_m(NH_4OH)}\]

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पाठ 3: Electrochemistry - Exercises [पृष्ठ ३६]

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एनसीईआरटी एक्झांप्लर Chemistry Exemplar [English] Class 12
पाठ 3 Electrochemistry
Exercises | Q I. 16. | पृष्ठ ३६

संबंधित प्रश्‍न

The conductivity of 0.20 mol L−1 solution of KCl is 2.48 × 10−2 S cm−1. Calculate its molar conductivity and degree of dissociation (α). Given λ0 (K+) = 73.5 S cm2 mol−1 and λ0 (C1) = 76.5 S cm2 mol−1.


Why does the conductivity of a solution decrease with dilution?


The conductivity of sodium chloride at 298 K has been determined at different concentrations and the results are given below:

Concentration/M 0.001 0.010 0.020 0.050 0.100
102 × κ/S m−1 1.237 11.85 23.15 55.53 106.74

Calculate ∧m for all concentrations and draw a plot between ∧m and c1/2. Find the value of `Lambda_m^0`.


Conductivity of 0.00241 M acetic acid is 7.896 × 10−5 S cm−1. Calculate its molar conductivity and if `Lambda_m^0` for acetic acid is 390.5 S cm2 mol−1, what is its dissociation constant?


10.0 grams of caustic soda when dissolved in 250 cm3 of water, the resultant gram molarity of solution is _______.

(A) 0.25 M

(B) 0.5 M

(C) 1.0 M

(D) 0.1 M


Conductivity always decreases with decrease in concentration both, for weak and strong electrolytes because of the fact that ____________.


Solutions of two electrolytes ‘A’ and ‘B’ are diluted. The Λm of ‘B’ increases 1.5 times while that of A increases 25 times. Which of the two is a strong electrolyte? Justify your answer.


When acidulated water (dil.H2SO4 solution) is electrolysed, will the pH of the solution be affected? Justify your answer.


Consider figure and answer the question to given below.

How will the concentration of Zn2+ ions and Ag+ ions be affected after the cell becomes ‘dead’?


Which of the following halogen acids is the strongest reducing agent?


The molar conductivity of CH3COOH at infinite dilution is 390 Scm2/mol. Using the graph and given information, the molar conductivity of CH3COOK will be:


Given below are two statements:

Statements I: The limiting molar conductivity of KCl (strong electrolyte) is higher compared to that of CH3COOH (weak electrolyte).

Statement II: Molar conductivity decreases with decrease in concentration of electrolyte.
In the light of the above statements, choose the most appropriate answer from the options given below:


Conductivity of 2 × 10−3 M methanoic acid is 8 × 10−5 S cm−1. Calculate its molar conductivity and degree of dissociation if `∧_"m"^0` for methanoic acid, is 404 S cm2 mol−3.


The following questions are case-based questions. Read the passage carefully and answer the questions that follow:

Rahul set up an experiment to find the resistance of aqueous KCl solution for different concentrations at 298 K using a conductivity cell connected to a Wheatstone bridge. He fed the Wheatstone bridge with a.c. power in the audio frequency range 550 to 5000 cycles per second. Once the resistance was calculated from the null point, he also calculated the conductivity K and molar conductivity ∧m and recorded his readings in tabular form.
S. No. Conc.
(M)
k S cm−1 m S cm2 mol−1
1. 1.00 111.3 × 10−3 111.3
2. 0.10 12.9 × 10−3 129.0
3. 0.01 1.41 × 10−3 141.0

Answer the following questions:

(a) Why does conductivity decrease with dilution? (1)

(b) If `∧_"m"^0` of KCl is 150.0 S cm2 mol−1, calculate the degree of dissociation of 0.01 M KCI. (1)

(c) If Rahul had used HCl instead of KCl then would you expect the ∧m values to be more or less than those per KCl for a given concentration? Justify. (2)

OR

(c) Amit a classmate of Rahul repeated the same experiment with CH3COOH solution instead of KCl solution. Give one point that would be similar and one that would be different in his observations as compared to Rahul. (2)


The specific conductance of 2.5 × 10-4 M formic acid is 5.25 × 10-5 ohm-1 cm-1. Calculate its molar conductivity and degree of dissociation.

Given `λ°_("H"^+)` = 349.5 ohm-1 cm2 mol-1 and

`λ°_("HCOO"^-)  = 50.5 " ohm"^-1 "cm"^2  "mol"^-1`


The resistance of a conductivity cell with a 0.1 M KCl solution is 200 ohm. When the same cell is filled with a 0.02 M NaCl solution, the resistance is 1100 ohm. If the conductivity of 0.1 M KCl solution is 0.0129 ohm-1 cm-1, calculate the cell constant and molar conductivity of 0.02 M NaCl solution.


The solution of two electrolytes A and B are diluted. ^m of B increases 1.5 times while that of A increases 25 times. Which of the two is a strong electrolyte? Give a reason.


Discuss the variation of conductivity and molar conductivity with concentration.


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