The bleaching action of sulphur dioxide is temporary because it involves the process of reduction. Sulphur dioxide removes oxygen from the coloured substance and makes it colourless. Atmospheric oxygen slowly takes place of the removed oxygen and because of which the material regains its colour.
Why does sulphur dioxide act as a bleach?
Sulphur dioxide acts as bleaching agent in the presence of moisture. Discuss. In the presence of moisture, sulphur dioxide is oxidised to H2SO4 liberating nascent hydrogen. The latter reduces coloured substances due to reduction.
Is SO2 a bleaching agent?
SO2 gas is used as a bleaching agent. Its bleaching action is temporary due to its reducing action. Here S oxidises to higher oxidation state and it reduces other compound.
What type of material is bleached by SO2?
SO2 reduces ferric salts into ferrous salt changing the colour from yellow to light green. Sulphur dioxide (SO2) is a temporary bleaching agent. 2[H] + colouring matter → Colourless matter.
Does SO2 bleach oxidation?
Sulphur dioxide (SO2) is a temporary bleaching agent. 2[H] + colouring matter → Colourless matter. Sulphur dioxide removes oxygen from the coloured substance and makes it colourless. Bleaching by sulphur dioxide is temporary as atmospheric oxygen re-oxidizes the bleached matter after some time.
What is the action of SO2?
Acid rain occurs when released into the atmosphere by sulfur dioxide (SO2) and nitrogen oxides (NOX) and carried by wind and air currents. The SO2 and NOX react to form sulfuric and nitric acids with water, oxygen, and other chemicals.
What is sulfur dioxide used in?
Although its chief uses are in the preparation of sulfuric acid, sulfur trioxide, and sulfites, sulfur dioxide also is used as a disinfectant, a refrigerant, a reducing agent, a bleach, and a food preservative, especially in dried fruits.
What is the best bleaching agent?
Hydrogen peroxide is best known for its bleaching reactions at alkaline pH in mechanical and chemical pulp bleaching as well as deinking. Hydrogen peroxide can also be used as a starting chemical for the production of peroxy acids.
Which agent is used in bleaching?
The chemistry of bleaching agents is predominantly that of oxidizing agents: chlorine (Cl2) and some of its compounds or peroxygen species such as hydrogen peroxide (H2O2), ozone (O3), and sodium perborate (NaBO3).
What is the action of chlorine on SO2?
Chlorine’s bleaching action is based on oxidation, whereas sulphur is based on reduction. Chlorine produces nascent oxygen as it reacts with water. As oxygen reacts with a coloured material, it turns it colourless. Sulphur dioxide depletes the oxygen content of the coloured material, rendering it colourless.
What is the difference between bleaching action of SO2 and Cl2?
The key difference between bleaching action of SO2 and Cl2 is that bleaching action of SO2 proceeds through a reduction reaction and is a temporary bleaching process whereas bleaching action of Cl2 proceeds through an oxidation reaction and is a permanent bleaching process.
Why is chlorine used for bleaching action?
When chlorine reacts with water, it produces nascent oxygen. This nascent oxygen combines with colored substances present in organic matter, and oxidizes it to colorless substances.Bleaching action of chlorine is permanent because it involves the oxidation process.
Why does chlorine show bleaching action?
Chlorine reacts with water to form hydrochloric and hypochlorous acids. Hypochlorous acid is unstable and it easily dissociates to form nascent oxygen.Therefore, Bleaching action of chlorine is done by oxidation.
Why chlorine bleaches a substance permanent but SO2 does it temporarily?
Give reason. Cl2 bleaches by oxidation, while SO2 bleaches by reduction. When Chlorine react with water it form nascent oxygen which act as oxidising agent. Hence product bleached by SO2 is reoxidised by air to its original form.
Why the bleaching action of chlorine is permanent but SO2 is temporary?
The bleaching action of SO2 is temporary because it involves the process of reduction. SO2 removes oxygen from the coloured substance to make it colourless.
Why is ozone a strong bleaching agent?
Ozone acts as the strong bleaching agent. Ozone has the capability to provide oxygen as well as the nascent oxygen. This production of nascent oxygen actually causes the bleaching action as it bleaches the color on a permanent basis.
How does SO2 reacts with a chlorine and B NaOH?
SO2 + 4 NaOH + Cl2 → Na2SO4 + 2 NaCl + 2 H2O – Balanced equation | Chemical Equations online!
Why is SO2 used as a solvent in spite of its toxic nature?
Liquid SO₂ is a solvent. It is a solvent of intermediate dielectric constant. This makes it a better solvent for covalently bonded compounds. Organic compounds are covalently bonded.
Why is SO2 soluble in water?
From the given information, the solute is SO2 S O 2 that has polar nature. The solvent is water which is also polar. Therefore, SO2 S O 2 is soluble in water. Hence, SO2 S O 2 is a polar gas, is soluble in water.
Is SO2 a peroxide?
SO 2 is a reducing agent, H 2O 2 is an oxidizing agent. ; Colorless liquid with a slightly sharp odor. [Note: The pure compound is a crystalline solid below 12°F. Often used in an aqueous solution.]
Search by reactants (SO 2, H 2O 2)
| 1 | SO2 + H2O2 → H2SO4 |
|---|---|
| 4 | SO2 + H2O2 → H2O + SO3 |
Why is it SO2 and not so?
Since they are formed by the interaction between sulphur and O2 molecules, these compounds are called sulphur oxides. The key contrast between SO2 and SO3 is that SO2 has two atoms of oxygen bonded to a sulphur atom, whereas SO3 has three atoms of oxygen bonded to a sulphur atom.
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