Advertisements
Advertisements
Question
EΘ of Cu is + 0.34V while that of Zn is – 0.76V. Explain.
Advertisements
Solution
High ionisation enthalpy to change \[\ce{Cu(s)}\] to \[\ce{Cu^2+}\] is not balanced by hydration enthalpy. Therefore, it exhibits a positive EΘ value. However, \[\ce{Zn}\] exhibits a lower value of ionization enthalpy because a stable 3d10 configuration is attained after losing two electrons. The hydration energy for \[\ce{Zn^2+}\] is comparable to that of \[\ce{Cu^2+}\]. Therefore, E° for Zn is negative.
APPEARS IN
RELATED QUESTIONS
The elements of 3d transition series are given as: Sc Ti V Cr Mn Fe Co
Answer the following: Which element is a strong oxidising agent in +3 oxidation state and why?
Why do the transition elements have higher enthalpies of atomisation?
In 3d series (Sc to Zn), which element has the lowest enthalpy of atomisation and why?
Write down the number of 3d electrons in the following ion:
Cu2+
Indicate how would you expect the five 3d orbitals to be occupied for this hydrated ion (octahedral).
Which one of the following ions is coloured?
How would you account for the following?
Zr (Z = 40) and Hf (Z = 72) have almost identical radii.
An analysis shows that FeO has a non-stoichiometric composition with formula Fe0.95O. Give reason.
Account for the following :
Ti4+ is colourless whereas V4+ is coloured in an aqueous solutions.
Transition metals with highest melting point is ____________.
The magnetic nature of elements depends on the presence of unpaired electrons. Identify the configuration of transition element, which shows highest magnetic moment.
Which of the following ions show higher spin only magnetic moment value?
(i) \[\ce{Ti^3+}\]
(ii) \[\ce{Mn2+}\]
(iii) \[\ce{Fe2+}\]
(iv) \[\ce{Co3+}\]
Why does copper not replace hydrogen from acids?
The orientation of an atomic orbital is governed by
The standard electrode potentials of four elements A, B, C and D are – 3.05, – 1.66, – 0.40 and + 0.80. The highest chemical reactivity will be exhibited by
Which of the following transition metal is not coloured?
The oxidation state of Fe in [Fe(CO)5] is ______.
Write the number of unpaired electrons in Cr3+.
(Atomic number of Cr = 24)
Write the ionic equation for reaction of KI with acidified KMnO4.
The compounds of \[\ce{Ti^4+}\] ions are colourless due to ______.
Give a reason for the following.
Some transition metals and their compounds get attracted towards the magnetic field.
