Advertisements
Advertisements
प्रश्न
While sulphur dioxide and hydrogen peroxide can act as oxidising as well as reducing agents in their reactions, ozone and nitric acid act only as oxidants. Why?
Advertisements
उत्तर
- In sulphur dioxide (SO2), the oxidation number (O.N.) of S is +4 and the range of the O.N. that S can have is from +6 to –2.
Therefore, SO2 can act as an oxidising as well as a reducing agent. - In hydrogen peroxide (H2O2), the O.N. of O is –1 and the range of the O.N. that O can have is from 0 to –2. O can sometimes also attain the oxidation numbers +1 and +2. Hence, H2O2 can act as an oxidising as well as a reducing agent.
- In ozone (O3), the O.N. of O is zero and the range of the O.N. that O can have is from 0 to –2. Therefore, the O.N. of O can only decrease in this case. Hence, O3 acts only as an oxidant.
- In nitric acid (HNO3), the O.N. of N is +5 and the range of the O.N. that N can have is from +5 to –3. Therefore, the O.N. of N can only decrease in this case. Hence, HNO3acts only as an oxidant.
APPEARS IN
संबंधित प्रश्न
Justify that the following reaction is redox reaction:
\[\ce{CuO(s) + H2(g) → Cu(s) + H2O(g)}\]
Justify that the following reaction is redox reaction:
\[\ce{4BCl3(g) + 3LiAlH4(s) → 2B2H6(g) + 3LiCl(s) + 3 AlCl3(s)}\]
Fluorine reacts with ice and results in the change: \[\ce{H2O(s) + F2(g) → HF(g) + HOF(g)}\]
Justify that this reaction is a redox reaction.
Suggest a list of the substances where carbon can exhibit oxidation states from –4 to +4 and nitrogen from –3 to +5.
How do you count for the following observations?
When concentrated sulphuric acid is added to an inorganic mixture containing chloride, we get colourless pungent-smelling gas HCl, but if the mixture contains bromide then we get red vapour of bromine. Why?
Identify the substance oxidised, reduced, oxidising agent and reducing agent for the following reaction:
\[\ce{HCHO(l) + 2[Ag (NH3)2]+(aq) + 3OH–(aq) → 2Ag(s) + HCOO–(aq) + 4NH3(aq) + 2H2O(l)}\]
Identify the substance oxidised, reduced, oxidising agent and reducing agent for the following reaction:
\[\ce{Pb(s) + PbO2(s) + 2H2SO4(aq) → 2PbSO4(s) + 2H2O(l)}\]
Consider the reactions:
\[\ce{2S_2O_3^{(2-)}(aq) + l_2(S) -> S_4O_6^{(2-)}(aq) + 2l-(aq)}\]
\[\ce{S_2O_3^{(2-)}(aq) + 2Br_2(l) + 5H_2O(l) -> 2SO_4^{2-} (aq) + 4Br-(aq) + 10H+ (aq)}\]
Why does the same reductant, thiosulphate react differently with iodine and bromine?
Consider the reactions:
- \[\ce{H3PO2(aq) + 4 AgNO3(aq) + 2 H2O(l) → H3PO4(aq) + 4Ag(s) + 4HNO3(aq)}\]
- \[\ce{H3PO2(aq) + 2CuSO4(aq) + 2 H2O(l) → H3PO4(aq) + 2Cu(s) + H2SO4(aq)}\]
- \[\ce{C6H5CHO(l) + 2[Ag (NH3)2]+(aq) + 3OH–(aq) → C6H5COO–(aq) + 2Ag(s) + 4NH3 (aq) + 2 H2O(l)}\]
- \[\ce{C6H5CHO(l) + 2Cu^{2+}(aq) + 5OH–(aq) → No change observed}\]
What inference do you draw about the behaviour of Ag+ and Cu2+ from these reactions?
What sorts of informations can you draw from the following reaction ?
\[\ce{{(CN)}_{2(g)} + 2OH-_{(aq)} -> CN-_{(aq)} + CNO-_{(aq)} + H_2O_{(l)}}\]
Which of the following elements does not show disproportionation tendency?
Identify the correct statements with reference to the given reaction.
\[\ce{P4 + 3OH- + 3H2O -> PH3 + 3H2PO^{-}2}\]
(i) Phosphorus is undergoing reduction only.
(ii) Phosphorus is undergoing oxidation only.
(iii) Phosphorus is undergoing oxidation as well as reduction.
(iv) Hydrogen is undergoing neither oxidation nor reduction.
Assertion (A): Redox couple is the combination of oxidised and reduced form of a substance involved in an oxidation or reduction half cell.
Reason (R): In the representation \[\ce{E^Θ_{Fe^{3+}/Fe^{2+}}}\] and \[\ce{E^Θ_{Cu^{2+}/Cu}, Fe^{3+}/Fe^{2+}}\] and \[\ce{Cu^{2+}/Cu}\] are redox couples.
Write redox couples involved in the reactions given.
\[\ce{Cu + Zn^{2+} ->Cu^{2+} + Zn}\]
Write redox couples involved in the reactions given.
\[\ce{Br2 + 2Cl- -> Cl2 + 2Br-}\]
Which of the following examples does not represent disproportionation?
An acidified manganate solution undergoes disproportionation reaction. The spin-only magnetic moment value of the product having manganese in a higher oxidation state is ______ B.M. (Nearest integer)
The reaction of sulphur in alkaline medium is given below:
\[\ce{S8(s) + {a} OH^-(aq) -> {b} S^{2-}(aq) + {c} S2O^{2-}3(aq) + {d} H2O(l)}\]
The values of 'a' are ______. (Integer answer)
\[\ce{H2O2 -> H2O + O2}\]
This represents ______.
