Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main 202120 JulyEvening Shift
Exam
JEE Main
Year
2021
Date
20 July
Shift
Evening Shift
Subject
Chemistry
Chapter
Electrochemistry

JEE Main 2021 · 20 July · Evening Shift · Chemistry · Electrochemistry

Potassium chlorate is prepared by electrolysis of KCl in basic...

Potassium chlorate is prepared by electrolysis of KClKCl in basic solution as shown by following equation.

6OH−+Cl−→ClO3−+3H2O+6e−6{OH}^{-} + {Cl}^{-} \to {ClO}_{3}^{-} + 3{H}_{2}O + 6{e}^{-}

A current of xAxA has to be passed for 10h10h to produce 10.0g10 . 0g of potassium chlorate. the value of xx is __________. (Nearest integer)

(Molar mass of KClO3=122.6gmol−1F=96500C{KClO}_{3} = 122 . 6g{mol}^{- 1}F = 96500C)

Correct answer

0

Step-by-step solution

Given balanced equation is

60H⊝+C⊝l⟶ClO3−+3H2O+6e−\overset{⊝}{60H} + \overset{⊝}{C}l ⟶ {ClO}_{3}^{-} + 3{H}_{2}O + 6{e}^{-}

→10gKClO3⇒10122.6molKCO3\to 10{gKClO}_{3} ⇒ \dfrac{10}{122 . 6}{molKCO}_{3} in obtained

→\to from the above reaction, it is concluded that by
6F6F charge 1molKClO31{molKClO}_{3} is obtained.

→\to By the passage of 6F6F charge =1molKClO3= 1{molKClO}_{3}

∴∴ By the passage of x×10×60×6096500F\dfrac{x \times 10 \times 60 \times 60}{96500}F charge

=16×x×10×60×6096500= \dfrac{1}{6} \times \dfrac{x \times 10 \times 60 \times 60}{96500}

Now x×10×60×606×96500=10122.6\dfrac{x \times 10 \times 60 \times 60}{6 \times 96500} = \dfrac{10}{122 . 6}

⇒x=10×96560×122.6=965735.6=1.311≃1⇒ x = \dfrac{10 \times 965}{60 \times 122 . 6} = \dfrac{965}{735 . 6} = 1 . 311 ≃ 1

OR

W=EF×I×tW = \dfrac{E}{F} \times I \times t

10=122.696500×6×x×10×360010 = \dfrac{122 . 6}{96500 \times 6} \times x \times 10 \times 3600

X=1.311X = 1 . 311

Practice Electrochemistry on Quantrex Academy →

More from Electrochemistry

At 300 K, the molar conductivities of the aqueous solutions of three salts at two… JEE Advanced 2026Given at 298 K: E^ _ Fe^ 2+ /Fe = X Volt; E^ _ Fe^ 3+ /Fe = Y Volt. The E^ _ Fe^ 3+ /Fe^… JEE Main 2026For a general redox reaction Anode : Red_1 arrow Ox_1^ n_1^+ + n_1 e^- Cathode : Ox_2 +… JEE Main 2026Consider the following data. Electrolyte Λ^ ∘ _m (S cm ^2 mol ^ -1 ) BaCl_2 x_1 H_2SO_4… JEE Main 2026One half cell in a voltaic cell is constructed by dipping silver rod in AgNO_3 solution… JEE Main 2026At 298 K , the molar conductivity of x\% (w/w) MX solution (aqueous) is 123.5 S cm^2 mol^… JEE Main 2026An electrochemical cell, consist of the following two redox couples, M^ x+ (aq)/M(s) [E_… JEE Main 2026Consider the following two half-cell reactions along with the standard reduction… JEE Main 2026 Full Electrochemistry list All JEE Main PYQs