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3 years ago

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Two identical spoons are electroplated with Ag or Cd through the use of the electrolytic cells. A current of 5.00A was supplied

to each cell for 600. seconds, and the masses of the spoons before and after the electroplating were recorded. Write down the mathematical equations can best be used to account for the much larger increase in mass of the spoon electroplated with Ag compared with the spoon electroplated with Cd.

1 answer:

OLga [1]3 years ago

4 0

Answer:

Explanation:

One farad of charge is capable of depositing one gram equivalent of a metal

One gram equivalent of Ag = 108 grams

One gram equivalent of Cd = 112 / 2 grams

= 56 grams . [ for cadmium equivalent mass = atomic mass / s ]

electric charge flowing = current x time = 5 x 600 = 3000 coulomb

one farad = 96500 coulomb

96500 coulomb deposits 108 gram of Ag

3000 coulomb deposits 108 x 3000 / 96500 gram

= 3.35 grams of Ag

Similarly ,

96500 coulomb deposits 56 gram of Cd

3000 coulomb deposits 56 x 3000 / 96500 gram

= 1.74 grams of Cd

So there will be much larger increase in the spoon of Ag due to larger deposit of Ag by charge .

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Answer : The rate of reaction is,

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The expression for rate of reaction will be :

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$Rate=-\frac{1}{a}\frac{d[A]}{dt}=-\frac{1}{b}\frac{d[B]}{dt}=+\frac{1}{c}\frac{d[C]}{dt}=+\frac{1}{d}\frac{d[D]}{dt}$

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In the rate of reaction, A and B are the reactants and C and D are the products.

a, b, c and d are the stoichiometric coefficient of A, B, C and D respectively.

The negative sign along with the reactant terms is used simply to show that the concentration of the reactant is decreasing and positive sign along with the product terms is used simply to show that the concentration of the product is increasing.

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The rate law expression will be:

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$[O_3]$ = $1.59\times 10^{-7}M$

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