KCET · Chemistry · Electrochemistry
A current of 3 A is passed through a molten calcium salt for 1 hr 47 min 13 s . The mass of calcium deposited is
(Molar mass of \(\mathrm{Ca}=40 \mathrm{~g} \mathrm{~mol}^{-1}\) )
- A 6.0 g
- B 2.0 g
- C 8.0 g
- D 4.0 g
Answer & Solution
Correct Answer
(D) 4.0 g
Step-by-step Solution
Detailed explanation
Given,
\(t=1 \mathrm{hr} 47 \mathrm{~min} 13 \mathrm{sec}=6433\) seconds
Molar mass of \(\mathrm{Ca}=40 \mathrm{~g} / \mathrm{mol}\)
Current \((i)=3 A\)
Mass of calcium deposited \((w)=\) ?
Using Faraday's \(2^{\text {nd }}\) law
\(w=z i t\) ....(i)
where, \(z=\frac{M}{n \times 96500}=\frac{40}{2 \times 96500}\)
Substitute the value of \(Z\) and given values in equation (i)
\(W=\frac{40 \times 3 \times 6433}{2 \times 96500}=3.99 \mathrm{~g} \approx 4 \mathrm{~g}\)
\(t=1 \mathrm{hr} 47 \mathrm{~min} 13 \mathrm{sec}=6433\) seconds
Molar mass of \(\mathrm{Ca}=40 \mathrm{~g} / \mathrm{mol}\)
Current \((i)=3 A\)
Mass of calcium deposited \((w)=\) ?
Using Faraday's \(2^{\text {nd }}\) law
\(w=z i t\) ....(i)
where, \(z=\frac{M}{n \times 96500}=\frac{40}{2 \times 96500}\)
Substitute the value of \(Z\) and given values in equation (i)
\(W=\frac{40 \times 3 \times 6433}{2 \times 96500}=3.99 \mathrm{~g} \approx 4 \mathrm{~g}\)
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Chemistry
- The value of rate constant of a pseudo first order reactionKCET 2018 Easy
- The amount of current in Faraday is required for the reduction of \( 1 \mathrm{~mol} \) of \( \mathrm{Cr}_{2} \mathrm{O}_{7}{ }^{2-} \) ions to
\( C r^{3+} \) is,KCET 2016 Hard - The time required for \(60 \%\) completion of a first order reaction is \(50 \mathrm{~min}\).
The time required for \(93.6 \%\) completion of the same reaction will beKCET 2020 Medium - In the preparation of sodium fusion extract, the purpose of fusing organic compound with a piece of sodium metal is toKCET 2025 Medium
- In the reaction,
\(\begin{aligned} 2 \mathrm{FeSO}_{4}+\mathrm{H}_{2} \mathrm{SO}_{4}+\mathrm{H}_{2} \mathrm{O}_{2} & \longrightarrow \\ & \mathrm{Fe}_{2}\left(\mathrm{SO}_{4}\right)_{3}+2 \mathrm{H}_{2} \mathrm{O} \end{aligned}\)
the oxidising agent isKCET 2013 Medium - At \(500 \mathrm{~K}\), for a reversible reaction \(A_2(g)+B_2(g) \rightleftharpoons 2 A B(g)\) in a closed container, \(K_C=2 \times 10^{-5}\). In the presence of catalyst, the equilibrium is attaining 10 times faster. The equilibrium constant \(K_C\) in the presence of catalyst at the same temperature isKCET 2023 Easy
More PYQs from KCET
- In the detection of II group acid radical, the salt containing chloride is treated with concentrated sulphuric acid, the colourless gas is liberated. The name of the gas isKCET 2021 Medium
- When a flower has both stamens and carpels it is described asKCET 2024 Hard
- A certain prism is found to produce a minimum deviation of \( 38^{\circ} . \) It produces a deviation of \( 44^{\circ} \)
when the angle of incidence is either \( 42^{\circ} \) or \( 62^{\circ} \). What is the angle of incidence when it is
undergoing minimum deviation?KCET 2019 Easy - The particles emitted in the decay of \( { }_{92}^{238} U \) to \( { }_{92}^{234} U \):KCET 2017 Medium
- The general solution of \(1+\sin ^{2} x=3 \sin x \cdot \cos x, \tan x \neq \frac{1}{2}\), isKCET 2010 Medium
- n photons of wavelength \(\lambda\) are absorbed by a black body of mass \(\mathrm{m}\). The momentum gained by the body isKCET 2012 Easy