Question

Equivalent weight of As2O3 in As2O3+2I2+2H2O--->As2O5+4HI

Answer 1

Answer:

Answer is 123.01g/equivalent

Explanation:

This is a redox reaction , so in order to determine the equivalent weight in this type or reactions, we have to follow this equations:

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where; O.A is an oxidizing agent and R.A is a reducing agent.

First, we can obtain the molecular weight of Arsenic sulfide from the Periodic Table of elements which is 246.02g/mol .

Second, we have to follow the change in oxidation number of As before the reaction and after it to determine the valency.

-As a reactant , the oxidation number of As in As2S3 is (+3)

-As a product , the oxidation number of As in (AsO4)-3 is (+5)

Hence, the change in oxidation number is 2 which is the absolute difference between them.

By substitution in the equation, the equivalent weight of As2S3 is 123.01g/equivalent .

Answer 2

Answer:

Equivalent weight of As2O3 in the given reaction is 49.5

Explanation:

Oxidation state per As atom in As2O3 is 6/2 = +3

Oxidation state per As atom in As2O5 is 10/2 = +5

Therefore the change in oxidation state for 1 As atom is +2

Therefore the change in oxidation state for 2 As atoms (since there are 2 atoms of arsenic in As2O3) is 2 x 2 = +4

So a net change in oxidation state of +4 has taken place in the reaction.

This change in oxidation state is also commonly called the n factor.

Therefore the n factor of As2O3 in this reaction is 4

Now, the molecular weight of As2O3 = (2 x 75) + (3 x 16) = 198

Equivalent Weight= (Molecular Weight / n factor) = 198 / 4 = 49.5