F2and Cl2are produced by electrolytic oxidation, whereasBr2andl2are produced by chemical oxidation of the halide ions in a concentrated aqueous solution (brine) by a more electronegative halogen. Give two reasons whyCl2isn't prepared this way.

Short Answer

Expert verified

1. BecauseCl2 is highly electronegative, a very strong oxidizing agent such as manganese dioxide MnO2or sodium dichromateNa2Cr2O7 and severe conditions are required for its preparation.

2. Since the source of - Cl-ions is table salt , moltenNaCl/CaCl2 mixture is employed to obtain a pure Na. On a big scale, chlorine gas is obtained as a 'by-product' on the anode.

Step by step solution

01

Oxidation

Oxidation is the loss of electrons, while reduction is the gain of electrons. When neutral atoms or molecules gain or lose electrons, such as those on an electrode's surface, they become ions, which can dissolve in the electrolyte and react with other ions.

Chemical oxidation reduces residual COD, non-biodegradable chemicals, and trace organic compounds using oxidation reagents such as hydrogen peroxide, chlorine dioxide, and ozone.

02

Explanation

1. Chlorine is highly electronegative,it is rarely synthesized through chemical oxidation.

Halogens' electronegativity drops as they go down Group7 (17) from F to I.

Non-metals such as fluorine and chlorine are extremely electronegative and thus are excellent oxidizing agents to oxidize a highly powerful oxidizing substance such as manganese dioxide or sodium dichromate. As a result, the chemical oxidation of anions is not advantageous because severe conditions are required.

2. In the industry, table salt is also a common source of manufacturing. A molten mixture is utilized to obtain a pure one. On the anode, chlorine gas is produced as a 'by-product.'

Anode (oxidation):2Cl-(l)Cl2(g) + 2e-

Cathode (reduction): 2Na+(l) + 2e-2Na(l).

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Most popular questions from this chapter

Several transition metals are prepared by reduction of the metal halide with magnesium. Titanium is prepared by the Kroll method, in which ore (ilmenite) is converted to the gaseous chloride, which is then reduced to metal by molten Mg(see p. 1008). Assuming yields of 84% for step 1 and 93% for step 2, and an excess of the other reactants, what mass of Ti metal can be prepared from 21.5 metric tons of ilmenite?

Step 1 of the Ostwald process for nitric acid production is

4NH3(g) + 5O2(g)Pt/Rh Catalyst4NO(g) + 6H2O(g)

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localid="1663401758011" 4NH3(g) + 3O2(g)2N2(g) + 6H2O(g)

(a) Calculate Kpfor these two NH3oxidations at 25oC.

(b) Calculate Kp for these two NH3 oxidations at localid="1663399666887" 900oC.

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The following steps are unbalanced half-reactions involved in the nitrogen cycle. Balance each half-reaction to show the number of electrons lost or gained, and state whether it is an oxidation or a reduction (all occur in acidic conditions):

(a)N2(g)NO(g)

(b)N2O(g)NO2(g)

(c)NH3(aq)NO2-(aq)

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(a) Use these two unbalanced steps to write an overall balanced equation for this process:

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