What is the basic difference between the terms electron gain enthalpy and electronegativity?
The first and the second
ionization enthalpies (in kJ mol-1) and the
electron gain enthalpy (in kJ mol-1) of a few elements are given below:
Elements
I 520 7300 -60
II 419 3051 -48
III 1681 3374 -328
IV 1008 1846 -295
V 2372 5251 +48
VI 738 1451 -40
Which of the above elements is likely to be:
(a) the least reactive element.
(b) the most reactive metal.
(c) the most reactive non-metal.
(d) the least reactive non-metal.
(e) the metal which can form a stable binary halide of the formula MX2(X =halogen).
(f) the metal which can form a predominantly stable covalent halide of the formula MX(X= halogen)?
The plot of square root of frequency of X-ray emitted against atomic number led to suggestion of which law/rule?
Periodic law
Modern periodic law
Hund's rule
Newland's law
Which of the following represents the correct order of increasing first ionisation enthalpy for Ca, Ba, S, Se and Ar?
Ca <S<Ba<Se<Ar
S< Se<Ca<Ba< Ar
Ba< Ca<Se< S< Ar
Ba< Ca<Se< S< Ar
C.
Ba< Ca<Se< S< Ar
Ionisation energy increases along period from left to right and decreases down a group. The position of given elements in the periodic table is as;
Increasing order of first ionization enthalpy is Ba < Ca < Se < S < Ar
The first ionisation potential of Na is 5.1 eV. The value of electron gain enthalpy of Na+ will be
-2.55 eV
-5.1 eV
-10.2 eV
-10.2 eV
The increasing order of the ionic radii of the given isoelectronic species is
Cl-, Ca2+, K+, S2-
S2-, Cl-, Ca2+,K+
Ca2+, K+, Cl-, S2-
Ca2+, K+, Cl-, S2-
The outer electron configuration of Gd (Atomic No : 64) is
4f3 5d5 6s2
4f8 5d0 6s2
4f4 5d4 6s2
4f4 5d4 6s2
The correct sequence which shows decreasing order of the ionic radii of the elements is
Al3+ > Mg2+ > Na+ > F- > O2-
Na+ > Mg2+ > Al3+ > O2- > F-
Na+ > F- > Mg2+ > O2- > Al3+
Na+ > F- > Mg2+ > O2- > Al3+
The set representing the correct order of ionic radius is
Li+> Be2+> Na+> Mg2+
Na+>Li+>Mg2+> Be2+
Li+>Na+ > Mg2+ > Be2+
Li+>Na+ > Mg2+ > Be2+