CBSE
Identify [A] and [B] in the following
Po, Rn
Th, Po
Ra, Th
Th, Ra
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
In haemoglobin, the metal ion present is
Fe2+
Zn2+
Co2+
Cu2+
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
Which element has highest electronegativity ?
F
He
Ne
Na
Which of the following statements about the interstitial compounds is incorrect?
They retain metallic conductivity
They are chemically reactive
They are much harder than the pure metal
They have higher melting points than the pure metal
Which of the following orders regarding ionisation energy is correct?
N > O > F
N < O < F
N > O < F
N < O < F
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
Identify the least stable ion amongst the following.
Li-
Be-
B-
C-
The electronic configuration 1s2, 2s22p6, 3s23p63d9 represents a
metal atom
non metal atom
non-metallic anion
metallic cation