Question

balance the following equation by
oxidation number
machod

Cr2O7^2- + H2SO4 ---- Cr^3+
+ H2 SO4​

Answer 1

Answer:

This is an oxidation-reduction (redox) reaction:

3 SIV - 6 e- → 3 SVI

(oxidation)

2 CrVI + 6 e- → 2 CrIII

(reduction)

SO2 is a reducing agent, Cr2O72- is an oxidizing agent.

Explanation:

This is an oxidation-reduction (redox) reaction:

3 SIV - 6 e- → 3 SVI

(oxidation)

2 CrVI + 6 e- → 2 CrIII

(reduction)

SO2 is a reducing agent, Cr2O72- is an oxidizing agent.

Reactants:

Cr2O72-

SO2 – Sulfur dioxide source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02source: NIOSH NPG, accessed: 2019-09-02

Other names: Sulfurous anhydride source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Sulphur dioxide source: ICSC, accessed: 2019-09-04source: wikidata, accessed: 2019-09-02, Sulfurous acid anhydride source: wikidata, accessed: 2019-09-02source: NIOSH NPG, accessed: 2019-09-02

Appearance: Colorless gas source: wikipedia, accessed: 2019-09-28; Colourless gas or compressed liquefied gas with pungent odour source: ICSC, accessed: 2019-09-04; Colorless gas with a characteristic, irritating, pungent odor. [Note: A liquid below 14°F. Shipped as a liquefied compressed gas.] source: NIOSH NPG, accessed: 2019-09-02

H+

Products:

Cr3+

SO42- – Sulfate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-07

Other names: Sulfate ion source: wikidata, accessed: 2019-09-07, Sulphate ion source: wikidata, accessed: 2019-09-07, Sulphate source: wikidata, accessed: 2019-09-07

H2O – Water, oxidane source: wikipedia, accessed: 2019-09-27

Other names: Water (H2O) source: wikipedia, accessed: 2019-09-27, Hydrogen hydroxide (HH or HOH) source: wikipedia, accessed: 2019-09-27, Hydrogen oxide source: wikipedia, accessed: 2019-09-27

Appearance: White crystalline solid, almost colorless liquid with a hint of blue, colorless gas source: wikipedia, accessed: 2019-09-27