Advertisements
Advertisements
प्रश्न
Assertion: pure iron when heated in dry air is converted with a layer of rust.
Reason: Rust has the compositionFe3O4.
विकल्प
if both assertion and reason are true and reason is the correct explanation of assertion.
if both assertion and reason are true but reason is not the correct explanation of assertion.
assertion is true but reason is false.
both assertion and reason are false.
उत्तर
both assertion and reason are false.
Explanation:
Both are false
- Dry air has no reaction with iron
- Rust has the composition \[\ce{Fe2O3.{x} H2O}\]
APPEARS IN
संबंधित प्रश्न
A certain current liberated 0.504 gm of hydrogen in 2 hours. How many grams of copper can be liberated by the same current flowing for the same time through copper sulphate solution.
A gas X at 1 atm is bubbled through a solution containing a mixture of 1MY− and 1MZ− at 25°C. If the reduction potential of Z > Y > X, then ____________.
Describe the construction of Daniel cell. Write the cell reaction.
Write a note on sacrificial protection.
Which of the following statement is correct?
For the given cell, \[\ce{Mg | Mg^{2+} || Cu^{2+} | Cu}\]
(i) \[\ce{Mg}\] is cathode
(ii) \[\ce{Cu}\] is cathode
(iii) The cell reaction is \[\ce{Mg^+ Cu^{2+} -> Mg^{2+} + Cu}\]
(iv) \[\ce{Cu}\] is the oxidising agent
Consider the following diagram in which an electrochemical cell is coupled to an electrolytic cell. What will be the polarity of electrodes ‘A’ and ‘B’ in the electrolytic cell?
In a Daniel cell, ______.
On which electrode the oxidation reaction takes place?
If the value of Ksp for Hg2Cl2 (s) is X then the value of X will be ____ where pX = - log X.
Given:
\[\ce{Hg2Cl2 + 2e- -> 2Hg(l) + 2Cl-}\], E° = 0.27 V
\[\ce{Hg+2 + 2e- -> 2Hg(l)}\] E° = 0.81 V
