Which ion is colourless?
Cr4+
Sc3+
Ti3+
V4+
B.
Sc3+
d-d transition is responsible for colour of compound. For d-d transition, ions have unpaired electrons in d-orbital. Sc3+ has no electrons in d-orbital, so d-d transition is not possible, hence, Sc3+ ion is colourless.
Four successive members of the first row transition elements are listed below with their atomic numbers. Which one of them is expected to have the highest third ionisation enthalpy?
Vanadium (Z = 23)
Manganese (Z = 25)
Chromium (Z= 24)
Iron (Z = 26)
The d-block elements consists mostly of
mono-valent metals
all non-metals
elements which generally form stoichiometric metal oxide
many metals with catalytic properties
Which element from group V gives most basic compound with hydrogen?
Nitrogen
Bismuth
Arsenic
Phosphorus
Which one of the following is an example of non-typical transition elements?
Li, K, Na
Be, Al, Pb
Zn, Cd, Hg
Ba, Ca, Sr
Point out in which of the following properties oxygen differs from the rest of the members of its family (Group-VIA)?
High value of ionisation energies
Oxidation states (2,4,6)
Polymorphism
Formation of hydrides
Which of the following statement is not correct?
La(OH)3 is less basic than Lu(OH)3.
In lanthanide series ionic radius of Lu3+ ion decreases.
La is actually an element of transition series rather lanthanide.
Atomic radius of Zr and Hf are same because of lanthanide contraction.
Which of the following properties increases on going down from F to I in group VII-A of the periodic table?
Electronegativity
Volatile nature
Ionic radius
Oxidising power
E°= -0.44V for the reaction, Fe2+ + 2e- → Fe and E°= -0.76 V for the reaction, Zn2+ + 2e- → Zn. Which of the following statement is correct?
Fe is more electropositive
Zn is more electropositive
Zn is more electronegative
None of the above
