The atomic numbers of elements A, B, C and D are Z - 1; Z; Z + 1 and Z + 2, respectively. If 'B' is a noble gas, choose the correct answers from the following statements-
1) 'A' has higher electron affinity.
(2) 'C' exists in +2 oxidation state.
(3) 'D' is an alkaline earth metal.
(1) and (2)
(2) and (3)
(1) and (3)
(1), (2) and (3)
The correct order of reducing abilities of hydrides of V group elements is
NH3 < PH3 < AsH3 < SbH3 < BiH3
NH3 > PH3 > AsH3 > SbH3 > BiH3
NH3 < PH3 > AsH3 > SbH3 > BiH3
SbH3 > BiH3 > AsH3 > NH3 > PH3
A radioactive substance 88X228 (IIA) emit 3α and 3β particles to form "Y". To which group of long form of the periodic table does "Y" belong ?
IVA
VA
VIA
VIIA
Which one of the following order is correct for the first ionisation energies of the elements?
B < Be < N < O
Be < B < N < O
B < Be < O < N
B < O < Be < N
Which one of the following is correct order of second ionisation potential of Na, Ne, Mg and Al?
Al < Na < Mg < Ne
Ne < Al < Na < Mg
Mg < Al < Ne < Na
Na < Mg < Ne < Al
Identify the most acidic oxide among the following oxides based on their reaction.
SO3
P4O10
Cl2O7
N2O5
Match the following:
List - I | List - II |
A. Rubidium | 1. Germanium |
B. Platinum | 2. Radioactive chalcogen |
C. Eka-silicon | 3. s-block element |
D. Polonium | 4. Atomic number 78 |
A - 4; B - 3; C - 2; D - 1
A - 3; B - 4; C - 1; D - 2
A - 2; B - 1; C - 4; D - 3
A - 4; B - 3; C - 1; D - 2
Identify the correct statement.
Lead forms compounds in +2 oxidation state due to inert pair effect.
All halogens show only negative oxidation state.
Catenation property increases from boron to oxygen.
Oxadation state of oxygen is - 1 in ozonides.
An element has [Ar] 3d1 configuration in its +2 oxidation state. Its position in the periodic table is
period - 3, group - 3
penod - 3, group - 7
period - 4, group - 3
period - 3, group - 9
C.
period - 4, group - 3
Electronic configuration of the element in +2 oxidation state is [Ar] 3d1. This electronic configuration is obtained after losing 2 electrons.
Atomic number of the element
= Atomic number of Ar + 1 + 2
= 18 + 1 + 2
= 21
Thus, element is Scandium. It is a d-block element. The electronic configuration of Sc = [Ar] 3d1 4s2.
Here, n = 4; therefore, it belongs to 4th period.
Group = Total number of valence shell electrons = 3
So, the element belongs to period - 4 and group - 3.