The p-Block Elements

Definition of P Block

Elements having a place within the group 13 (i.e. group IIIA) to group 17 (i.e. group VIIA) of the periodic table alongside the group 18 i.e. the zero group elements together frame the p-block of the periodic table.
 

Position of P Block Elements in the Periodic Table

In the elements of p-block, the last electron enters the furthest p orbital. They have 3 to 8 electrons in the peripheral shell. As we realize that the quantity of p orbitals is three and, therefore, the most extreme number of electrons that can be obliged in an arrangement of p orbitals is six. Consequently, there are six groups of p-block elements in the periodic table numbering from 13 to 18.

First group: group IIIA called as Boron group

Second group: group IVA called as Carbon group.

Third group: group VA called as Nitrogen group.

Fourth group: group VIA called as Chalcogens.

Fifth group: group VIIA called as Halogens.

Sixth group: zero group or group 18 called as Inert or Noble gasses group.

In the p-block, all the three sorts of elements are available, i.e. the Metals, Non-Metals, and Metalloids.The crisscross line in the p-block isolates every one of the elements that are metals from those that are non-metals. Metals are found on the left of the line, and non-metals are those on the right. Along the line, we discover the metalloids. Because of the nearness of a wide range of elements, the p-block demonstrates a great deal of variety in properties.

Fig. 1: Position of P block in the periodic table

Elements in the p-block of the Periodic Table

The elements in the p-block of the periodic table comprises of a wide range of elements i.e. metals, non-metals and metalloids.

• Metals:

1. Aluminium

2. Gallium

3. Indium

4. Thallium

5. Tin

6. Lead

7. Bismuth

• Non-Metals:

1. Helium

2. Carbon

3. Nitrogen

4. Oxygen

5. Fluorine

6. Neon

7. Phosphorus

8. Sulphur

9. Chlorine

10. Argon

11. Selenium

12. Bromine

13. Krypton

14. Iodine

15. Xenon

16. Radon

• Metalloids

1. Boron

2. Silicon

3. Germanium

4. Arsenic

5. Antimony

6. Tellurium

7. Polonium

8. Astatine
    

Characteristic Properties of Elements in p-Block of Modern Periodic Table

Electronic Configuration

The general valence shell electronic design of p-block elements is ns 2 np^1-6 (with the exception of He). The internal core of the electronic arrangement may although contrast.

The general electronic configuration appeared by elements from group13 to 18 of p-block is as given underneath:-

Group 13 (Boron family) :- ns² np¹

Group 14 (Carbon family) :- ns² np²

Group 15 (Nitrogen family) :- ns² np³

Group 16 (Oxygen family) :- ns² np⁴

Group 17 (Halogen family) :- ns ² np⁵

Group 18 (Noble gases) :- ns² np⁶ (except Helium)

The general electronic configuration of Helium is 1s². Because of their particular electronic configuration p-block elements demonstrate a great deal of variety in properties.
 

Metallic Character

As stated before p-block contains a wide range of elements i.e. metals, non-metals, and metalloids. The p-block is the main locale of the periodic table to contain metalloids.The nonmetallic character diminishes down the group though there is a progressive increment in non-metallic character from left to right in the p-block. The metallic character tends to increment down every group while it diminishes as we go from left to right over a period. As a matter of fact, the heaviest element in every p-block group is the most metallic in nature.
 

Fig. 2: Above figure shows the metals, non metals and the metalloids in P- Block 

Atomic Density

The Atomic Density of elements in p-block increments down the group, this is because of increment in the atom's size down the group. Though it diminishes as we move from left to right over the period, this is because of the lessening in nuclear size of all elements in the p-block over the period. Of the considerable number of elements, aluminum is of low density and is generally utilized as a structural material.

Melting and Boiling Points

The Melting and Boiling points slowly increment down the group in light of the fact that the atomic mass increments down the group and thus the intermolecular forces also increase.

Fig. 3: The structural variation leads to irregular trends in group 13-16.

In the other sides, the melting point of group 17 and 18 increase as down the group due to stronger intermolecular forces (van der Waals interaction).
 

Oxidation State

The p-block elements demonstrate a variable oxidation state. The oxidation states increments as we move from left towards right in the periodic table. The greatest oxidation state appeared by a p-block element is equivalent to the aggregate number of valence electrons. As indicated by this, the oxidation states appeared by different groups are as per the following:

Boron family (Group 13): - + 3

Carbon family (Group 14): - + 4

Nitrogen family (Group 15): - + 5

Oxygen family (Group 16): - + 6

Halogen family (Group 17): - + 7

Noble gases (Group 18): - + 8

In any case, notwithstanding these p-block elements may likewise indicate other oxidation states which typically may differ from an aggregate number of valence electrons by a unit of two. The other oxidation state two units not exactly the group oxidation state appeared by different groups are as per the following:

Boron family (Group 13): - + 1

Carbon family (Group 14):- + 2, -4

Nitrogen family (Group 15):- + 3, -3

Oxygen family (Group 16): - + 4, + 2, -2

Halogen family (Group 17): - + 5, + 3, + 1, -1

Noble gases (Group 18): - + 6, + 4, + 2

In any case, the relative inertness of these two oxidation states i.e. the group oxidation state and the other oxidation state two unit less than the group oxidation state, may shift from group to group.

Atomic and Ionic Radii

As we move down the group in the p-block one additional shell than the previous element gets included into the following element. This at last increases the nuclear and the ionic radius of each next element down the group, which at last demonstrates that the nuclear and the ionic radii increment down the group. The pattern is not same over the period. As we move towards right in a period the Atomic radii and the Ionic radii of p-block elements diminishes. The atomic radius increases enormously from Boron to Aluminum. This expansion is because of more prominent screening impact created by the eight electrons exhibited in the penultimate shell.

Fig. 4: Atomic radius of p block elements

Fig. 5: Trend in atomic radius in p block elements

Fig. 6: Trends in ionic radius in p block elements

Electrode Potential

The p-block elements by and large have a positive anode potential. It, for the most part, decreases down the groups.

For e.g. Consider the anode possibilities of the halogen group:

Fluorine = 2.87 V

Chlorine = 1.36 V

Bromine = 1.09 V

Iodine = 0.53 V

From the above scientific data, we can state that the anode potential in the p-block diminishes down the groups.

IonizationEnergies

There are high ionization possibilities in p-block elements. The ionization energies of p-block elements increase towards right in a period because of effectively expanding atomic charge.

As indicated by the general patterns the ionization energy values diminishes down the group yet don't diminish smoothly. Ionization Energies in Non-metals is higher than metals. It is most extreme for a noble gas since noble gasses have totally filled configuration. A few elements at the base of a group like Lead, Tin, Thallium, Bismuth, and so forth acts nearly as a metal with low ionization energies.

Fig. 7: Trends of Ist ionization energy

Magnetic Properties

The p block elements Radon, Astatine, Iodine, and Polonium are Non-Magnetic in nature. Only Tin is Paramagnetic and the rest all elements of the p-block are Diamagnetic in nature.

Complex Formation

The small size and the more noteworthy charge of the elements of various groups of p-block empower them to have a more prominent propensity to form complexes as compared to the s-block elements. This tendency of forming complex diminishes down the group as the size of the atoms increments down the group.

Chemical Reactivity

The Chemical Reactivity of elements in the p-block increments as we move towards right in a period. Be that as it may, as we move down in a group the chemical reactivity of elements declines down the group.

i) Reactivity of Noble Gases: 

All the orbitals of the noble gasses are totally filled by electrons and it is exceptionally hard to break their stability in any way whether it is the removal of electrons or addition of electrons. Hence the noble gasses show low compound reactivity. In light of their low reactivity noble gasses, are regularly utilized when a nonreactive climate is required, for example, in welding.

Going before the noble gas family there are two chemically essential groups of non-metals. They are the halogens (Group 17) and the chalcogens (Group 16). These two groups of elements have high electron gain enthalpies and can promptly include one to two electrons framing an anion to achieve the steady noble gas configuration in this way indicating great chemical reactivity.

Further Reading: Group 18 elements

ii) Reactivity of Halogens:

a) All halogens are normally found in a combined form.

b) Fluorine reacts promptly with any substance interacting with it.

c) Chlorine, Bromine, and Iodine are dynamically less reactive yet at the same time frame compounds with most different elements, particularly metals.

d) All the halogens are solid oxidizing agents. The halogens oxidize different Substances, yet themselves get reduced.

e) All halogens react straightforwardly with sodium to frame sodium halides.

f) All halogens react with red phosphorus to shape phosphorus halides.

g) Halogens react promptly with alkali metals shaping salts.

h) Chlorine, Bromine, and Iodine presence can be identified by the treatment of acidified silver nitrate solution.

Further Reading: Group 17 elements

iii) Reactivity of group VIA Elements (Chalogens):

a) As we reach to deal with the right-hand side of the periodic table, likenesses among the elements inside a group get to be distinctly more noteworthy. This is valid for the group VIA except for polonium which is not considered in any discussions due to its radioactivity.

b) All individuals from the group VIA shape X^2– particles when reacted with exceedingly electropositive metals.

c) The propensity to be diminished to the - 2 oxidation state diminishes essentially as we move down.

d) At normal pressure and temperature, oxygen is a gas. It exists in both of the two allotropic structures: O₂, which makes up 21 percent of the world's air, or O₃ (ozone), which gradually decays to O₂.

e) The ozone itself ingests longer-wavelength ultraviolet radiations, keeping these harmful beams away from reaching the world's surface which would in some way or another expand the likelihood of human skin malignancy and can likewise bring about other environment related issues.

f) The Compounds of selenium and tellurium are of minimal business significance as they are dangerous.

Further Reading: Group 16 elements

iv) Reactivity of Metalloids:

a) The synthetic reactivity of the metalloids relies upon the substance with which it is reacting. For instance: - Boron acts as a nonmetal when reacting with sodium, however, it goes about as a metal when reacting with fluorine.

b) Thus, from the above illustration, we can state that Metalloids demonstrate variable chemical properties.

c) They act like non-metals when they react with metals though they act like metals when they react with non-metals.

d) Due to their low electro negativity, they are normally oxidized in reactions. The oxides of metalloids are generally amphoteric.

v) Reactivity of group VA Elements:

a) All the group VA elements upon reaction with hydrogen form trihydrides.

b) The reactivity diminishes down the group.

c) The elements in the group VA either frame trioxides or pentoxides when reacted with oxygen.

d) Also, they shape trihalides or pentahalides when reacted with halogens.

e) All the group VA elements react with metals to shape binary compounds.

f) The most vital compounds of the group VA elements are those of nitrogen and phosphorus.

g) Nitrogen and phosphorus are most generally utilized as manure.

Further Reading: Group 15 elements

vi) Reactivity of group IIIA Elements:

a) Dissimilar to groups IA and IIA, none of the group IIIA elements react specifically with hydrogen to frame hydrides.

b) Also, all the group IIIA elements react with halogens to shape trihalides rather than essentially halides like group IA and IIA elements.

Further Reading: Group 13 elements

vii) Reactivity of group IVA Elements:

a) Carbon has a capacity to shape solid bonds with other carbon molecules and along these lines frame an enormous assortment of organic compounds

b) In the +4 oxidation state lead goes about as a solid oxidizing agent, increasing two electrons and subsequent to picking up electrons it gets reduced to the +2 oxidation state.

c) Also in the +4 oxidation state lead frames covalent compounds and bonds firmly to carbon.

d) Besides the metals, themselves, some tin and lead mixes are of business significance. For Example: - Tin (II) fluoride (stannous fluoride) is added to some toothpaste to repress dental considerations.

e) Lead is likewise found in two principle business applications. One, the lead-acid storage batteries used to begin autos and the other is in the vehicle fuel.

Further Reading: Group 14 elements

Conductivity: - The conductivity of elements in p-block increments down the group. The metals present in the p-block are good conductors of electricity and heat while the non-metals are poor conduits of electricity and heat. The conductivity of metalloids lies in the middle of the metals and non-metals.
 

Color

Color of group IIIA elements:

All elements are silvery solids except boron which is brown solid.

Color of group IVA elements:

Carbon: black in color

Silicon and germanium: reddish brown or dull grey or black color

Lead: bluish-white color 

Color of group VA elements:

Nitrogen: colorless

Phosphorus: white and red

Arsenic: yellow and grey solid form

Antimony: amorphous grey form

Bismuth: silvery white

Color of group 16 elements:

Oxygen: is a colorless gas

Sulphur: pale yellow

Tellurium: silvery-white

All the Halogens are colored. They have following colors:

Fluorine: - Pale yellow.

Chlorine: - Greenish yellow.

Bromine: - Reddish brown.

Iodine: - Violet black.

Noble Gases have following colors:

Helium: Red

Neon: Orange

Krypton: Purple

Xenon: White

Radon: Colorless
 

Flame Coloration

Not everything except rather a couple of p-block elements grant characteristic color to the flame.

Boron imparts Bright green color

Copper (I) impart Blue color

Copper (II) (non-halide) impart Green color

Copper (II) (halide) impart Blue- green color

Indium and selenium impart Blue color

Phosphorus impart Pale bluish green color

Lead impart Blue/White color

Antimony and Tellurium impart Pale green color

Thallium imparts pure green color

Fig. 8: Summary of the trends in properties of p block elements
 

Frequently Asked Questions (FAQs)

Q1. What do elements in the P block have in common?

Sol. The p-block is the range of the periodic table containing segments 3A to section 8A (segments 13-18), excluding helium. There are 35 p-block elements, all of which have valence electrons in the p orbital. The p-block elements are an exceptionally differing group of elements with an extensive variety of properties.

Q2. What is the name of p block elements? 

Sol. Representative Elements.

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