In Periodic Table, the basic character of oxides
increases from left to right and decreases from top to bottom
decreases from right to left and increases from top to bottom
decreases from left to right and increases from top to bottom
decreases from left to right and increases from bottom to top
Which of the following orders regarding ionisation energy is correct?
N > O > F
N < O < F
N > O < F
N < O < F
The electronic configuration 1s2, 2s22p6, 3s23p63d9 represents a
metal atom
non metal atom
non-metallic anion
metallic cation
In a given shell the order of screening effect is
s > p > d > f
s > p > f > d
f > d > p > s
s < p < d < f
The ionisation energy of hydrogen atom is 13.6eV. What will be the ionisation energy of He+?
13.6 eV
54.4 eV
122.4 eV
Zero
The correct order of radii is
N <Be <B
F-<O2-<N3-
Na< Li< K
Fe3+< Fe2+< Fe4+
B.
F-<O2-<N3-
These are isoelectronic species and their radii decreases with increasing their atomic number due to increasing effective nuclear charge (Zeff).
where, Zeff = effective nuclear charge, Z= atomic number and = screening constant. For F-, O2- and N3-, the value of is the constant due to equal number of electron. So order of Zeff is F > O2-> N3-, hence, order of radii is