Transition And Inner Transition Elements Flashcards
What is the oxidation state of manganese in?
i) MnO4 2-
ii)MnO4 -
i)+6
ii)+7
Give uses of KMnO4
1)an Antiseptic
2) for unsaturation test in laboratory
3) in volumetric analysis of reducing agents
4) for detecting halides in qualitative analysis
5) powerful oxidizing agent in laboratory and industry.
Why salts of Sc3+, Ti4+, V5+ are colourless?
Sc3+ salts are colorless
The electronic configuration of 21Sc [Ar] 3d1 4s2 and s³+ [ArJd0.
Ti4+ salts are colorless
The e.c of 22 Ti [Ar] 3d² 4s² Ti⁴+ [Ar]d0
V⁵+ salts are colorless
The e.c of 23 V [Ar]3d³ 4s² & V⁵+[Ar]3d0.
Since there are no unpaired electrons in 3d subshell, d—-d transition is not possible.
Therefore, Sc³+,Ti⁴+, V⁵+ions do not absorb the radiation in the visible region. Hence salts of Sc³+ Ti⁴+ and V⁵+ are colourless.
Which steps are involved in manufacture of potassium dichromate from chromite ore?
Steps in manufacture of potassium dichromate from chromate ore are
1) concentration of chromite ore
2) conversion of chromite or into sodium chromate
3) conversion of sodium chromate into sodium dichromate
4) conversion of sodium dichromate into potassium dichromate
Stable oxidation state of plutonium cerium manganese Europium
Plutonium - +3 to +7
Cerium - +3, +4
Manganese - +2, +4, +6, +7
Europium - +2, +3
Write electronic configuration of chromium and copper
24Cr : 1s2 2s2 2p6 3s2 3p6 3d5 4s1
29 Cu : 1s2 2s2 2p6 3s2 3p6 3d10 4s1
What is meant by shielding of electrons in an atom?
The inner shell electron in an atom screen or shield outermost electron from nuclear attraction. This effect is called shielding effect. The magnitude of shielding effect depends upon the number of inner electrons.
Explain the trends in atomic radii of d block elements
The atomic radii of elements of transition elements are intermediate between those of s block and p block elements of the same period.
Atomic radii of transition elements decrease with increase in atomic number.
In transition elements the last electron enters (n - 1) d subshell. when the d electrons after poor screening effective nuclear charge increases.
Hence atomic radii decrease with increase in atomic number.
The decrease in atomic radii is less. There is slight increase in atomic radius of last two elements Cu and Zn.
What are the difference between cast iron and brought iron and steel?
1)Cast iron
Hard and brittle
Contains 4% carbon
Used for making pipes, manufacturing automotive parts, pots, pan, utensils.
2) Wrought iron
Very soft
Contains less than 0.2% carbon
Used for making pipes, bars for stay bolts, engine bolts and rivelts
3) steel
Neither too hard not too soft
Contains 0.2 to 2% carbon
Used in building infrastructure, tools, ship ,automobile ,weapon etc.
Give the similarities and differences in elements of 3d, 4d and 5d series.
Similarity
1) they are place between s block and p block of the periodic table
2) all elements are metals showing metallic character
3) some are paramagnetic
4) most of them give coloured compounds
5) they have catalytic property
6) they form complexes
7) they have variable oxidation State.
Differences
1) in 4D and 5D series lanthanide and actinoid contraction is observed. In 3D series atomic size changes are less mark.
2) 4D and 5D elements have high coordination numbers compared to 3D elements.
3) 4D and 5D series have similar properties whereas 3D series have different properties.
What is meant by diamagnetic and paramagnetic metal? Give an example of diamagnetic and paramagnetic transition metal and lanthanoid metal
Paramagnetic metal
When a magnetic field is applied, substance which are attracted towards the applied magnetic field are called paramagnetic substances
Example and Ni2+, Pr4+
Diamagnetic metal
When a magnetic field is applied, substance which are repel by the magnetic field are called diamagnetic substance
Example Zn2+, La3+
Write steps involved in metallurgical process
The various steps and principles involved in the extraction of pure metals from their ores are as follows
1) concentration of ores in which impurities (gangue) are removed
2) conversion of ores into oxides or other reducable compounds of metals
3) reduction of ores to obtain crude metal
4) refining of metals giving pure metals.
