The document discusses the extraction of metals from ores. It begins by explaining that metals are found either in their free state or combined as compounds in minerals and ores. It then outlines some common metal ores such as bauxite (Al2O3.2H2O) for aluminum, zinc blende (ZnS) for zinc, and hematite (Fe2O3) for iron. Finally, it notes that the steps in extracting metal from ore depend on the reactivity of the metal. Highly reactive metals require more processing steps since they must be extracted from their ionic compounds in the ore. Less reactive metals like gold and silver are sometimes found in their free state.
Chapter 3.metals and non metals priya jhaPriya Jha
An element is the simplest form of matter that cannot be split into simpler substances or built from simpler substances by any ordinary chemical or physical method. There are 118 elements known to us, out of which 92 are naturally occurring, while the rest have been prepared artificially. Elements are further classified into metals, non-metals, and metalloids based on their properties, which are correlated with their placement in the periodic table.Metals
With the exception of hydrogen, all elements that form positive ions by losing electrons during chemical reactions are called metals. Thus metals are electropositive elements with relatively low ionization energies. They are characterized by bright luster, hardness, ability to resonate sound and are excellent conductors of heat and electricity. Metals are solids under normal conditions except for Mercury.Nonmetals
Elements that tend to gain electrons to form anions during chemical reactions are called non-metals. These are electronegative elements with high ionization energies. They are non-lustrous, brittle and poor conductors of heat and electricity (except graphite). Non-metals can be gases, liquids or solids.Metalloids
Metalloids have properties intermediate between the metals and nonmetals. Metalloids are useful in the semiconductor industry. Metalloids are all solid at room temperature. They can form alloys with other metals. Some metalloids, such as silicon and germanium, can act as electrical conductors under the right conditions, thus they are called semiconductors. Silicon for example appears lustrous, but is not malleable nor ductile (it is brittle - a characteristic of some nonmetals). It is a much poorer conductor of heat and electricity than the metals. The physical properties of metalloids tend to be metallic, but their chemical properties tend to be non-metallic. The oxidation number of an element in this group can range from +5 to -2, depending on the group in which it is located.
Topics Included
• Introduction
• Metals
→ Physical properties of metals
→ Chemical Properties of metals
• Non-metals
→ Physical properties of non-metals
→ Chemical Properties of metals
• Difference between metals and non-metals
• Reaction with Acids
• Reaction with Bases
Chapter 3.metals and non metals priya jhaPriya Jha
An element is the simplest form of matter that cannot be split into simpler substances or built from simpler substances by any ordinary chemical or physical method. There are 118 elements known to us, out of which 92 are naturally occurring, while the rest have been prepared artificially. Elements are further classified into metals, non-metals, and metalloids based on their properties, which are correlated with their placement in the periodic table.Metals
With the exception of hydrogen, all elements that form positive ions by losing electrons during chemical reactions are called metals. Thus metals are electropositive elements with relatively low ionization energies. They are characterized by bright luster, hardness, ability to resonate sound and are excellent conductors of heat and electricity. Metals are solids under normal conditions except for Mercury.Nonmetals
Elements that tend to gain electrons to form anions during chemical reactions are called non-metals. These are electronegative elements with high ionization energies. They are non-lustrous, brittle and poor conductors of heat and electricity (except graphite). Non-metals can be gases, liquids or solids.Metalloids
Metalloids have properties intermediate between the metals and nonmetals. Metalloids are useful in the semiconductor industry. Metalloids are all solid at room temperature. They can form alloys with other metals. Some metalloids, such as silicon and germanium, can act as electrical conductors under the right conditions, thus they are called semiconductors. Silicon for example appears lustrous, but is not malleable nor ductile (it is brittle - a characteristic of some nonmetals). It is a much poorer conductor of heat and electricity than the metals. The physical properties of metalloids tend to be metallic, but their chemical properties tend to be non-metallic. The oxidation number of an element in this group can range from +5 to -2, depending on the group in which it is located.
Topics Included
• Introduction
• Metals
→ Physical properties of metals
→ Chemical Properties of metals
• Non-metals
→ Physical properties of non-metals
→ Chemical Properties of metals
• Difference between metals and non-metals
• Reaction with Acids
• Reaction with Bases
CBSE Class 8 / VIII General Ccience Power Point Presentation
Prepared By
Praveen M Jigajinni
DCSc & Engg,PGDCA,ADCA,MCA,MSc(IT),MTech(IT), M.Phil (Comp Sci)
For Any Queries Please feel free to contact:
Email Id : praveenkumarjigajinni@gmail.com
Cell No: 9431453730
This presentation describes lots about the metals and non-metals. It also talks about the periodic tabe, physical and chemical properties of metals and non-metals and usses of them. Go ahead and learn beyond the Earth's crust as scientists still continue to dicover new things around the earth. After going through this presentation you will have complete understanding about the metals and non-metals.
Enjoy!!
What are the acids? examples, where to find?
What are the bases? examples, where to find?
Neutralization concept and examples
all easy to understand and remember.
The following power point discusses about the Chemical Effects of Electric Current. In this, we study about how electricity is conduced in liquids, electrolysis and the uses and applications of it
CBSE Class 8 / VIII General Ccience Power Point Presentation
Prepared By
Praveen M Jigajinni
DCSc & Engg,PGDCA,ADCA,MCA,MSc(IT),MTech(IT), M.Phil (Comp Sci)
For Any Queries Please feel free to contact:
Email Id : praveenkumarjigajinni@gmail.com
Cell No: 9431453730
This presentation describes lots about the metals and non-metals. It also talks about the periodic tabe, physical and chemical properties of metals and non-metals and usses of them. Go ahead and learn beyond the Earth's crust as scientists still continue to dicover new things around the earth. After going through this presentation you will have complete understanding about the metals and non-metals.
Enjoy!!
What are the acids? examples, where to find?
What are the bases? examples, where to find?
Neutralization concept and examples
all easy to understand and remember.
The following power point discusses about the Chemical Effects of Electric Current. In this, we study about how electricity is conduced in liquids, electrolysis and the uses and applications of it
Metals and Non-Metals form a fundamental classification of elements, playing a pivotal role in understanding the diverse world of chemistry. In Class 10, students delve into the distinct characteristics, properties, and reactions that define these two broad categories. Metals, with their conductivity and malleability, stand in stark contrast to the non-metals, which exhibit varying physical and chemical traits. These notes provide a concise exploration of the essential attributes of metals and non-metals, offering a foundational understanding for students to navigate the complexities of chemical interactions and classifications in the realm of science.
This is a summary of the topic "metals" in the GCE O levels subject: Chemistry. Students taking either the combined science (chemistry/physics) or pure chemistry will find this useful. These slides are prepared according to the learning outcomes required by the examinations board.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Multi-source connectivity as the driver of solar wind variability in the heli...
Metals & non metals
1.
2. There are 118 elements known at present .
All elements can broadly classified as metals
and nonmetals.
A majority of elements are metals ,except
mercury which is liquid at room temperature.
There are 22 non metals :10- solid , 1 liquid i.e.
bromine and 11 gases
INTRODUCTION
4. The left hand side of periodic table and in the
centre are placed the metals .
It may be noted that hydrogen (H) is an
exception because it is nonmetal but placed
on left side of the table.
The elements close to the zig zag line show
the property of both metals and nonmetals .
These are called metalloids. Commom
example are Boron(B), silicon(S),
germanium(Ge), arsenic(As), antimony(Sb).
POSITION OF METALS AND NON
METALS IN PERIODIC TABLE
5. Continued
Metallic character decreases from left to right
Increases from top to bottom
Left extreme are most metallic and right
extreme are least metallic.
6. All metals are solid at room temperature.
Exception : Mercury (liquid)
Most metals are malleable i.e. can be
hammered into thin sheets without breaking.
Gold, Silver, Aluminum etc. are some highly
malleable metals
Metals are ductile, it means metals can be
drawn into thin wires. About 2 km length can
be drawn from one gram gold.
Physical properties of metals
7. Metals are good conductors of heat. The
conduction of heat is called thermal conductivity.
Silver is the best conductor of heat. Lead is poorest
conductor of heat . Mercury is also a good
conductor
Metals are also good conductors of electricity .
The electrical and thermal conductivities are due to
presence of free electrons . Silver is again the best
conductor of electricity. But since silver is
expensive , therefore copper and aluminum are
commmonly used.
Physical properties of metals
8. Metals are lustrous.
Metals have high densities. Eg. Mercury has
high density (13.6 g/cm3 ). Sodium and
potassium are exceptions.
Metals are generally hard . Sodium and
potassium are exception which can be cut with
a knife
Metals have high melting and boiling points.
Tungsten has the highest 34100C
Physical properties of metals
9. Metals are rigid.
Metals are sonorous.
Physical properties of metals
10. When a metal has been kept exposed to air for
long time, its appearance becomes dull due to
formation of layer of oxide, hydroxide, carbonate
of the metal by slow action of moisture and gases
present in the air. This process is termed as
corrosion. This the reason why further reaction
between Al and air is not possible( though a thin
layer of Al2O3 forms)
Why metal article on rubbing becomes
brighter?
11. Non-Metals are brittle.
Non-Metals are not ductile.
Non-Metals are bad conductors of heat and
electricity(Except Graphite due to free electrons)
Non-Metals may be solid , liquid or gas at STP.
Non-Metals are generally soft.(Exception: Diamond)
Non-Metals have low melting and boiling
points(Exception: Diamond and Graphite)
Non-Metals have low densities( Exception: Iodine).
Physical properties of non-metals
12. Metal atoms have usually 1,2 or 3 electrons in their
outermost shells.These outermost electrons are loosely
held by the nuclei.As a consequence they can easily loose
electrons to form positively charged ions.
Na Na+ + e-
Mg Mg2+ + 2e-
Al Al3+ + 3e-
As a result metals are called electropositive elements.
Chemical Properties Of Metal
13. Metals react with Oxygen to form Metal
Oxides.These oxides are basic in nature.When
these oxides are dissolved in water they give
alkaline solutions.
Eg:4Na + O2 2Na2O
2Na2O + H2O NaOH
ReactionWith Oxygen
14. All metals do not react with Oxygen at
equal ease.
Reactivity with oxygen depends upon
the nature of metal.
Reactivity of metals towards Oxygen:
15. 1.Metals like Sodium, Potassium
and Calcium react with Oxygen
even at room temperature to form
oxides.
4Na(s) + O2(g) 2Na2O(s)
4K(s) + O2(g) 2K2O(s)
2Ca(s) + O2(g) 2CaO(s)
16. 2.Metals like Magnesium donot react with
oxygen at Room temperature.They burn in air
on heating to form correspondind oxides.
2Mg(s) + O2(g) + Heat 2MgO(s)
3.Metals like Zinc react with oxygen only on
strong heating.
2Zn(s) + O2(g) + Heat 2ZnO(s)
17. 4.Metals like Iron and Copper do not
burn in air in strong heating. They react
with oxygen only on prolonged heating.
2Cu(s) + O2(g) + Heat 2CuO(s)
3Fe(s) + 2O2(g) + Heat Fe3O4(s)
18. Metals react with water to form metal oxide/metal hydroxide and
hydrogen.The reactivity of the metal depends upon the nature.
1. Sodium and Potassium react vigorously with cold water to form
respective hydroxides and hydrogen gas is liberated.The reaction is
so vigorously that hydrogen gas catches fire.
2Na(s) + 2H2O(l) 2NaOH(aq) + H2(g)
2K(s) + 2H2O(l) 2KOH(aq) + H2(g)
2. Calcium reacts with cold water to form calcium hydroxide but the
reaction I less violent.
Ca(s) + 2H2O(l) Ca(OH)2(aq) + H2(g)
Reaction With Water
19. 3. Magnesium reacts very slowly with cold water
but reacts rapidly with hot boiling water forming
Magnesium oxide and hydrogen.
Mg(s) + H2O(l) MgO(s) + H2(g)
4. Metals like zinc and aluminium react with
steam to form oxides and hydrogen.
Zn(s) + H2O(g) ZnO(s) + H2(g)
2Al(s) + H2O(g) Al2O3(s) + 3H2(g)
20. 5. Iron reacts with water only when steam is
passed over red hot iron. The products are
Iron(II,III) Oxide and hydrogen.
3Fe(s) + 4H2O(g) Fe2O4(aq) + 4H2(g)
6.Metals like Copper, Gold and Silver do not react
with water even under strong conditions.
21. 1.Sodium, Magnesium and Calcium react violently with Hydrochloric
Acid(HCl) or dilute Sulphuric Acid (H2SO4) liberating hydrogen gas and
metal salt.
2Na(s) + 2HCl (aq) 2NaCl(aq) + H2(g)
2Na(s) + H2SO4 (aq) Na2SO4(aq) + H2(g)
2.Alumunium and Zinc react with dilute HCl or dilute H2SO4 liberating
hydrogen gas and corresponding metal salt.
2Al(s) + 6HCl (aq) 2AlCl3(aq) + 3H2(g)
2Al(s) + 3H2SO4 (aq) Al2(SO4)3(aq) + 3H2(g)
2Zn(s) + 2HCl (aq) ZnCl2(aq) + H2(g)
2Zn(s) + H2SO4 (aq) ZnSO4(aq) + H2(g)
Reaction with Dilute Acids
22. 3.Iron reacts slowly with dilute HCl or dil.H2SO4.
Fe(s) + 2HCl (aq) FeCl2(aq) + H2(g)
Fe(s) + H2SO4 (aq) FeSO4(aq) + H2(g)
4.Copper does not react with these acids.
Fe(s) + HCl (aq) no reaction
Fe(s) + H2SO4 (aq) no reaction
Dilute Nitric acid(HNO3) is an oxidizing agent but doesnot
produce hydrogen with metals.Exception in this case are
Mg & Mn.
23. When a more reactive metal is placed in a salt solution of a
less reactive metal,then the more reactive metal displaces the
less reactive metal from its salt solution.
Zn(s) + CuSO4(aq) ZnSO4 (aq) + Cu(s)
However a less reactive metal cannot displace a more reactive
metal.
Cu(s) + ZnSO4(aq) no reaction
Many metals react with dilute acids and liberate hydrogen
gas. Only less reactive metals such as Copper, Silver, Gold etc.
do not liberate hydrogen from dilute acids.
Reaction of metals with Salt solutions
24. Some metals are very reactive while others are very less
reactive.
On this basis they are arranged in decreasing order of their
reactivities.
This arrangement is called reactivity series.
REACTIVITY SERIES OF METALS
26. In the series of metals, the basis of reactivity is
the tendency of metals to lose electron. If a metal
loses electron easily to form a positive ion
(cation), it will react readily with other
substances. Therefore it will be more reactive
metal.
Eg: Alkali metals like sodium and potassium are
highly reactive metals.
Reasons for different Reactivities
27. All metals above hydrogen in the reactivity series(i.e.
more active than hydrogen) like Zn,Mg,Ni etc. can
liberate hydrogen from acids like HCl and
H2SO4.These metals have greater tendency to lose e-
from hydrogen.
All metals below hydrogen in the reactivity series(i.e.
Less active than hydrogen) like Au,Ag and Cu etc.
cannot liberate hydrogen from acids like HCl and
H2SO4.These metals have lesser tendency to lose e-
from hydrogen.Therefore they cannot give electron
to H+ ions.
Displacement of Hydrogen from Acids
by Metals:
28. In general,a more reactive metal(placed higher in
the activity series) can displace the less reactive
metal from its salt solution.
Eg: Zn(s) + CuSO4(aq) ZnSO4 (aq) + Cu(s)
Reactivity Series and Displacement
Reactions:
29. According to octet rule “an atom whose
outermost shell contains 8 electrons(octet) is
stable.But in case of small atoms like He and H in
which presence of 2 electrons in the outermost
shell is considered to be the condition of stability.
Interaction Of Metals and Non-Metals
31. Atoms combine with another to form inert gas
electron arrangement. An atom can achieve inert
gas configuration in the following ways:
I ) By losing one or more electrons
II) By gaining one or more electrons
III) By sharing one or more electrons
Note : noble gases do not usually form bonds with
other elements because they are stable.
36. Ionic compounds form crystals.
Ionic compounds form crystal latticce rather than
amorphous solids. Although molecular compounds form
crystals, they frequently take other forms plus molecular
crystals typically are softer than ionic crystals.
Ionic compounds have high melting points and high
boiling points.
High temperatures are required to overcome the
attraction between the positive and negative ions in ionic
compounds.Therefore, a lot of energy is required to melt
ionic compounds or cause them to boil.
Properties of ionic compounds
37. Ionic compounds have higher enthalpies of fusion and vaporization
than molecular compounds.
Just as ionic compounds have high melting and boiling points, they
usually have enthalpies of fusion and vaporization that may be 10 to 100
times higher than those of most molecular compounds. The enthalpy of
fusion is the heat required melt a single mole of a solid under constant
pressure. The enthalpy of vaporization is the heat required for vaporize
one mole of a liquid compound under constant pressure.
Ionic compounds are hard and brittle.
Ionic crystals are hard because the positive and negative ions are
strongly attracted to each other and difficult to separate, however, when
pressure is applied to an ionic crystal then ions of like charge may be
forced closer to each other. The electrostatic repulsion can be enough to
split the crystal, which is why ionic solids also are brittle.
Properties of ionic compounds
38. Ionic compounds conduct electricity when they are
dissolved in water.
When ionic compounds are dissolved in water the
dissociated ions are free to conduct electric charge
through the solution. Molten ionic compounds (molten
salts) also conduct electricity.
Ionic solids are good insulators.
Although they conduct in molten form or in aqueous
solution, ionic solids do not conduct electricity very well
because the ions are bound so tightly to each other.
Properties of ionic compounds
40. All metals are present in the earth’s crust either in
the free state or in the form of compounds.
Aluminium metal is the most abundant metal I
the earths crust. The second is iron and the third
is calcium.
Occurrence of metals
41. The natural substance in which metals or their componds
occur either in native state or combined state are called
minerals.
The minerals are not pure and contain different types of
other impurities.The impurities associated with minerals
are collectively known as gangue or matrix.The mineral
from which the metal can be conveniently and profitably
extracted is called ore.
For example : aluminium occurs in the earths crust in the
form of two minerals , bauxite(Al2O3.2H2O)and clay
(Al2O3.2SiO2.2H2O). out of these two , aluminium can be
profitably extracted from bauxite.Thus , bauxite is an ore
of aluminium.
Minerals And Ores
42. The most common ores of metals are oxides,
sulphides, halides, etc.
Very unreactive are present I free state.
Slightly reactive metals occur as sulphides
Reactive metals occur as oxides.
Most reactive metals occur as salts as carbonates,
sulphates, halides,etc.
Types Of Ores
46. Based upon reactivity series metals can be grouped as follows:
Metals of Low Reactivity:These metals are often found in free state in
nature.
Eg:Gold,Silver,Platinum
Metals of Medium Reactivity:The ores of these metals are found mainly in
oxides,sulphates and carbonates form.They are usually reduced using
carbon.
Eg:Zinc,Iron,Lead
Metals of High Reactivity:Metals at the top of the reactivity series are
never found in free state in nature.These are purified by electrolysis.
Extraction Of Metals:
47. Ores mined from earth are contaminated
with large amount of impurities called
gangue.The gangue is removed based on
differences of physical and chemical
particles of gangue and ore.
Enrichment Of Ores:
48. Metals low in the activity series are very unreactive.Their oxide
ore can be reduced to metals by heating alone.
Eg:Cinnabar(HgS) is an ore of mercury.It is first converted to
Mercuric oxide which on further heating gives Mercury.Similar is
the case for Copper too.The reactions involved are.
For Mercury:2HgS(s)+3O2(g)+Heat 2HgO(s) + 2SO2(g)
2HgO(s) +Heat Hg(l) + O2(g)
For Copper: 2Cu2S(s)+3O2(g)+Heat 2 Cu2O(s) + 2SO2(g)
2 Cu2O(s) + 2Cu2S(s)+Heat 6 Cu(s) + SO2(g)
Extracting Metals Low in the Activity
Series:
49. Metals in the middle of the activity series are usually present in sulphides and carbonates. It
is easier to obtain a metal from its oxide ore than sulphides or carbonates.
The sulphide ores are converted to oxide ore by strongly heating in the presence of excess
air. This process is known as roasting.
Eg: 2ZnS(s) + 3O2(g)+Heat 2ZnO(s) + 2SO2 (g)(Roasting)
The carbonate ore is strongly heated in the presence of limited air. This process is known as
Calcination.
Eg:ZnCO3 (s) ZnO(s)+ CO2(g) (Calcination)
The metal oxides are then reduced to the metals using suitable agents such as
carbon.Obtaining metals from their ores is a reduction process.
Eg:ZnO(s) + C(s) Zn(s) + CO(g)
Extracting Metals Middle in the Activity
Series:
50. The reactive metals such as Sodium, Calcium and
Aluminium etc. are used as reducing agents
because they can displace metals of lower
reactivity to produce metals.
Eg:3MnO2(s) + 4Al(s) 3Mn(l) + 2Al2O3 + Heat
The reactions are highly exothermic and hence
the required metals are produced in liquid state.
Eg:Fe2O3 (s) + 2Al (s) 2Fe(l) + 2Al2O3(s)+ Heat
(Thermit Reaction-Used to join railway tracks or
cracked machine parts)
51. The metals like Na,K,Mg,Ca,Al have more affinity to oxygen
than carbon.Hence their oxides can’t be reduced.These
metals are obtained only by Electrolytic reduction.These
metals are obtained mostly from their halide ores.The
metals are deposited at the cathode whereas the halogen
at anode.
Eg:At Cathode: Na+ + e- Na
At Anode: 2Cl- Cl2 + 2e-
Extracting Metals at theTop of Reactivity
Series:
52. The most widely used process for refining metals is
electrolytic refining.
Electrolytic Refining: In this process the impure metal is
made the anode and a strip of pure metal the cathode.A
solution of the metal salt is udes as electrolyte.On passing
electricity,pure metal from anode dissolves into the
electrolyte.An equivalent amount of metal from the
electrolyte is deposited on the cathode.The soluble
impurities go into the solution,whereas,the insoluble
impurities settle down at the bottom and is known as
anode mud.
Refining of Metals:
53. Corrosion is a natural process, which
converts refined metal to their more stable
oxide. It is the gradual destruction of
materials (usually metals) by chemical
reaction with their environment. In the
most common use of the word, this means
electrochemical oxidation of metal in
reaction with an oxidant such as oxygen.
Corrosion
55. Galvanization is the process of protecting steel
and iron from rusting by coating them with a thin
layer of zinc.
Galvanization
56. An alloy is a material composed of two or more metals or a
metal and a nonmetal. An alloy may be a solid solution of the
elements (a single phase), a mixture of metallic phases (two or
more solutions) or an intermetallic compound with no distinct
boundary between the phases. It helps in prevention of
corrosion.
Stainless Steel is an Alloy of Iron along with small amounts of
Manganese, Nickel, Chromium and Carbon.
Brass ia an alloy of Copper and Zinc.
Bronze is an alloy of Copper andTin.
If in an alloy one of the component is Mercury thn it is known as
Amalgam.
Solder is an alloy ofTin and Lead.
Alloys
