This document provides information about atoms and molecules:
1) It summarizes Dalton's atomic theory, including that atoms are indivisible and combine in small whole number ratios to form compounds.
2) It describes what atoms and molecules are, noting atoms are the smallest particle of an element and molecules are groups of atoms held together.
3) Key terms like atomic mass, molecular mass, ions, and the mole concept are defined to explain the mass and structure of substances at the atomic level.
AkWrite about different classes of people on the clothes Aman Pathak:
Conclusion on Trace the train in clothes worn at work,leisure, sports in the early 19th century qnd today in the world and india
Trace the impact of colonization on the handloom workers and industry and compare it with changes in handloom and khadi industry since independence in india with title
Conclusion of
Trace the impact of colonization on the handloom workers and industry and compare it with changes in handloom and khadi industry since independence in indiaAs mentioned earlier, "Chirag" is a two-word short story by Phanishwar Nath Renu. The story goes as follows:
A lamp was burning in a room. A gust of wind blew through the window and extinguished the flame. The end.
The story may seem simple and straightforward, but it has a deeper meaning. The lamp represents life, and the wind represents death. The sudden extinguishing of the lamp symbolizes how life can be snuffed out in an instant. It also emphasizes the fragility of life and how we should cherish every moment we have.
Overall, "Chirag" is a poignant and thought-provoking story that leaves a lasting impact on the reader.Write about different classes of people on the clothes they were when they wear youngAman Pathak:
Conclusion on Trace the train in clothes worn at work,leisure, sports in the early 19th century qnd today in the world and india
Trace the impact of colonization on the handloom workers and industry and compare it with changes in handloom and khadi industry since independence in india with title
Conclusion of
Trace the impact of colonization on the handloom workers and industry and compare it with changes in handloom and khadi industry since independence in indiaBuried Treasure
X: -104 Z: 1,176they were when they wear youngAs mentioned earlier, "Chirag" is a two-word short story by Phanishwar Nath Renu. The story goes as follows:
A lamp was burning in a room. A gust of wind blew through the window and extinguished the flame. The end.
The story may seem simple and straightforward, but it has a deeper meaning. The lamp represents life, and the wind represents death. The sudden extinguishing of the lamp symbolizes how life can be snuffed out in an instant. It also emphasizes the fragility of life and how we should cherish every moment we have.
Overall, "Chirag" is a poignant and thought-provoking story that leaves a lasting impact on the reader.Aman Pathak:
Conclusion on Trace the train in clothes worn at work,leisure, sports in the early 19th century qnd today in the world and india
Trace the impact of colonization on the handloom workers and industry and compare it with changes in handloom and khadi industry since independence in india with title
Conclusion of
Trace the impact of colonization on the handloom workers and industry and compare it with changes in handloom and khadi industry since independence in indiaWrite about different classes of people on the clothes they were when they wear y
AkWrite about different classes of people on the clothes Aman Pathak:
Conclusion on Trace the train in clothes worn at work,leisure, sports in the early 19th century qnd today in the world and india
Trace the impact of colonization on the handloom workers and industry and compare it with changes in handloom and khadi industry since independence in india with title
Conclusion of
Trace the impact of colonization on the handloom workers and industry and compare it with changes in handloom and khadi industry since independence in indiaAs mentioned earlier, "Chirag" is a two-word short story by Phanishwar Nath Renu. The story goes as follows:
A lamp was burning in a room. A gust of wind blew through the window and extinguished the flame. The end.
The story may seem simple and straightforward, but it has a deeper meaning. The lamp represents life, and the wind represents death. The sudden extinguishing of the lamp symbolizes how life can be snuffed out in an instant. It also emphasizes the fragility of life and how we should cherish every moment we have.
Overall, "Chirag" is a poignant and thought-provoking story that leaves a lasting impact on the reader.Write about different classes of people on the clothes they were when they wear youngAman Pathak:
Conclusion on Trace the train in clothes worn at work,leisure, sports in the early 19th century qnd today in the world and india
Trace the impact of colonization on the handloom workers and industry and compare it with changes in handloom and khadi industry since independence in india with title
Conclusion of
Trace the impact of colonization on the handloom workers and industry and compare it with changes in handloom and khadi industry since independence in indiaBuried Treasure
X: -104 Z: 1,176they were when they wear youngAs mentioned earlier, "Chirag" is a two-word short story by Phanishwar Nath Renu. The story goes as follows:
A lamp was burning in a room. A gust of wind blew through the window and extinguished the flame. The end.
The story may seem simple and straightforward, but it has a deeper meaning. The lamp represents life, and the wind represents death. The sudden extinguishing of the lamp symbolizes how life can be snuffed out in an instant. It also emphasizes the fragility of life and how we should cherish every moment we have.
Overall, "Chirag" is a poignant and thought-provoking story that leaves a lasting impact on the reader.Aman Pathak:
Conclusion on Trace the train in clothes worn at work,leisure, sports in the early 19th century qnd today in the world and india
Trace the impact of colonization on the handloom workers and industry and compare it with changes in handloom and khadi industry since independence in india with title
Conclusion of
Trace the impact of colonization on the handloom workers and industry and compare it with changes in handloom and khadi industry since independence in indiaWrite about different classes of people on the clothes they were when they wear y
This presentation is designed for the students of grades 11 and 12. You can know about the importance and scope of chemistry. Atomic mass, the process of naming compounds, acids, the chemical name of substances, and so on.
A PERFECT POWERPOINT PRESENTATION FOR CHAPTER ATOMS AND MOLECULES FOR CLASS 9. IT COVERS ALL THE MAJOR CONCEPTS AND TOPICS OF THE CHAPTER. HOPE YOU LIKE IT.
This presentation is designed for the students of grades 11 and 12. You can know about the importance and scope of chemistry. Atomic mass, the process of naming compounds, acids, the chemical name of substances, and so on.
A PERFECT POWERPOINT PRESENTATION FOR CHAPTER ATOMS AND MOLECULES FOR CLASS 9. IT COVERS ALL THE MAJOR CONCEPTS AND TOPICS OF THE CHAPTER. HOPE YOU LIKE IT.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
(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.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
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.
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.
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.
2. 1) Laws of chemical combination :-
i) Law of conservation of mass :- states that ‘Mass can neither be
created nor destroyed in a chemical reaction’.
This means that during a chemical reaction the sum of the masses of
the reactants and products remain unchanged.
Activity :-
Take some sodium sulphate solution in a conical flask and some
barium chloride solution in an ignition tube. Hang the ignition tube in
the flask by a thread and pot a cork on the flask. Find the mass of the
flask on a balance. Then tilt the flask. A chemical reaction takes place
and sodium chloride and barium sulphate are formed. Then find the
mass of the flask again. It will be seen that the sum of the masses of the
reactants and products remain unchanged.
BaCl2
solution
BaSO4 white
3. ii) Law of constant proportions :- states that ‘ In a chemical
compound the elements are always present in a definite proportion by
mass’.
Eg :- Water ( H2O) always contains two elements hydrogen and oxygen
combined together in the same ratio of 2:16 or 1:8 by mass. If 9 g of
water is decomposed we get 1 g of hydrogen and 8 g of oxygen.
Ammonia (NH3) always contains two elements nitrogen and
hydrogen combined together in the same ratio of 14:3 by mass.
4.
5. 2) Dalton’s atomic theory :-
i) Matter is made up of tiny particles called atoms.
ii) Atoms are indivisible and cannot be created or destroyed
in a chemical reaction
iii) Atoms of a given element are similar in mass and
properties.
iv) Atoms of different elements have different masses and
properties.
v) Atoms combine in small whole number ratios to form
compounds.
vi) In a given compound the relative number and kind of
atoms are constant.
6. 3) Atom :-
An atom is the smallest particle of an element that may or
may not exist independently and retains all its chemical
properties.
Atoms are very small in size and smaller than anything
we can imagine or compare with.
Atomic radius is measured in nanometres (nm)
1 nanometer = 10 -9 m or 1 meter = 109 nm
Eg :- The atomic radius of an atom of hydrogen is 10-10 m.
The radius of a molecule of water is 10-9 m.
7. 4) Symbols of atoms of different elements :-
The symbols of elements are represented by letters.
The symbols of some elements are represented by one letter and the
symbols of some elements are represented by two letters.
If the symbol has only one letter it should be written as capital letter
and if the symbol has two letters then the first letter should be capital
letter and the second letter should be small letter.
Symbols of some common elements :-
Element Symbol Element Symbol Element Symbol
Aluminium Al Copper Cu Nitrogen N
Argon Ar Fluorine F Oxygen O
Barium Ba Gold Au Potassium K
Boron B Hydrogen H Silicon Si
Bromine Br Iodine I Silver Ag
Calcium Ca Iron Fe Sodium Na
Carbon C Lead Pb Sulphur S
Chlorine Cl Magnesium Mg Uranium U
Cobalt Co Neon Ne Zinc Zn
8. 5) Atomic mass :-
Since atoms are very small in size its mass is very small and
determining its mass is very difficult. So the mass of an atom is
compared with the mass of a standard atom.
The atom which is considered as a standard atom for comparing the
masses of other atoms is carbon – 12 atom whose atomic mass is
12 u (atomic mass unit).
One atomic mass unit (u) is the mass of 1/12th the mass of a carbon –
12 atom.
The atomic mass of an element is defined as the average mass of one
atom of the element compared with 1/12th the mass of a carbon – 12
atom.
Atomic masses of some elements :-
Element Atomic mass (u) Element Atomic mass (u)
Hydrogen 1 Magnesium 24
Carbon 12 Aluminium 27
Nitrogen 14 Sulphur 32
Oxygen 16 Chlorine 35.5
Sodium 23 Calcium 40
9. 6) Molecule :-
A molecule is the smallest particle of an element or
compound which exists independently and shows all the
properties of that substance.
A molecule is a group of two or more elements that are
held together by attractive forces.
Atoms of the same element or different elements can join
together to form molecules.
10. i) Molecule of elements :-
Molecule of an element contains atoms of the same element.
Molecules of some elements contain only one atom and molecules of
some elements contain two or more atoms.
Atomicity of an element :- is the number of atoms present in
one molecule of the element.
Atomicity of some elements :-
Type of element Name Atomicity
Non metal Argon Ar 1 – Monoatomic
Non metal Helium He 1 – Monoatomic
Non metal Oxygen O2 2 – Diatomic
Non metal Hydrogen H2 2 – Diatomic
Non metal Nitrogen N2 2 – Diatomic
Non metal Chlorine Cl2 2 – Diatomic
Non metal Phosphorus P4 4 – Phosphorus
Non metal Sulphur S8 Poly atomic
Metal Sodium Na 1 – Monoatomic
Metal Iron Fe 1 – Monoatomic
Metal Aluminium Al 1 – Monoatomic
Metal Copper Cu 1 – Monoatomic
11. ii) Molecule of compounds :-
Molecule of a compound contains atoms of two or more different
types of elements.
Molecules of some compounds :-
Compound Combining elements Number of atoms of each
elements
Water – H2O Hydrogen, Oxygen 2 - Hydrogen, 1 - Oxygen
Ammonia – NH3 Nitrogen, Hydrogen 1 - Nitrogen, 3 - Hydrogen
Carbon dioxide
CO2
Carbon, Oxygen I - Carbon, 2 - Oxygen
Hydrochloric acid
HCl
Hydrogen, Chlorine 1 - Hydrogen, 1 - Chlorine
Nitric acid
HNO3
Hydrogen, Nitrogen, Oxygen 1 - Hydrogen, 1 - Nitrogen,
3 - Oxygen
Sulphuric acid
H2SO4
Hydrogen, Sulphur, Oxygen 2 - Hydrogen, 1 - Sulphur,
4 - Oxygen
12. 7) Ions :-
Compounds containing metal and non metal elements contain
charged particles called ions.
An ion is a charged particle having positive or negative charge. A
positively charged ion is called ‘cation’ and a negatively charged ion is
called ‘anion’.
Valency :- is the combining capacity of an element.
Some common ions and their valencies :-
Valency Name of ion Symbol Name of ion Symbol Name of ion Symbol
1 Sodium Na+ Hydrogen H + Ammonium NH 4
-
1 Potassium K+ Hydride H - Hydroxide OH -
1 Silver Ag+ Chloride Cl - Nitrate NO3
-
1 Copper (I) Cu+ Bromine Br - Hydrogen carbonate HCO3
-
2 Magnesium Mg 2+ Iodine I -
2 Calcium Ca 2+ Oxide O 2- Carbonate CO3
2-
2 Zinc Zn 2+ Sulphide SO3
2-
2 Iron (II) Fe 2+ Sulphate SO4
2-
2 Copper (II) Cu 2+
3 Aluminium Al 3+ Nitrate N 3- Phosphate PO4
3-
3 Iron (iii) Fe 3+
13. 8) Writing chemical formulae :-
i) Write the symbols / formula of the elements or ions so that the
symbol of the metal or positive ion is on the left and symbol / formula
of the non metal or negative ion is on the right.
ii) Write the valencies of the elements or ions below the elements or
ions.
iii) Cross over the valencies of the combining ions.
iv) Polyatomic ions should be enclosed in bracket before writing the
formula.
Examples :-
i) Formula of hydrogen chloride ii) Formula of hydrogen sulphide
Symbol H Cl Symbol H S
Valency 1 1 Valency 1 2
Formula HCl Formula H2S
iii) Formula of Magnesium chloride iv) Formula of Carbon tetrachloride
Symbol Mg Cl Symbol C Cl
Valency 2 1 Valency 4 1
Formula MgCl2 Formula CCl4
14. v) Formula of Calcium oxide vi) Formula of Aluminium oxide
Symbol Ca O Symbol Al O
Valency 2 2 Valency 3 2
Formula Ca2O2 = CaO Formula Al2O3
vii) Formula of Sodium nitrate viii) Formula of Calcium hydroxide
Symbol/ Na NO3 Symbol/ Ca OH
Formula Formula
Valency 1 1 Valency 2 1
Formula NaNO3 Ca(OH)2
ix) Formula of Sodium carbonate x) Formula of Ammonium sulphate
Symbol/ Na CO3 Symbol/ NH4 SO4
Formula Formula
Valency 1 2 Valency 1 2
Formula Na2CO3 (NH4)2SO4
15. 9) Molecular mass / Formula unit mass:-
The molecular mass of a substance is the sum of the
atomic masses of all the atoms in a molecule of the
substance.
Molecular mass is expressed in atomic mass units (u).
Eg:- Molecular mass of water – H2O
Atomic mass of H = I u
Atomic mass of O = 16 u
Molecular mass of H2O = 1x2+10 = 2+16 = 18 u
Molecular mass of Nitric acid – HNO3
Atomic mass of H = 1 u
Atomic mass of N = 14 u
Atomic mass of O = 16 u
Molecular mass of HNO3 = 1+14+16x3 = 1+14+48 = 63 u
16. 10) Mole concept :-
A mole of a substance is that amount of the substance which contains the
same number of particles (atoms, molecules or ions) that are present in 12g of
Carbon – 12.
The number of particles (atoms) present in 12g of Carbon – 12 is
6.022 x 1023 . This number is called Avagadro Number or Avagadro Constant.
A mole represents two things :-
i) It represents a definite number of particles (atoms, molecules or ions) equal to
6.022 x 1023 .
ii) It represents a definite mass of a substance equal to the gram atomic mass of
an element or the gram molecular mass of a compound.
Gram atomic mass of an element :- is its atomic mass expressed in grams.
Eg :- Gram atomic mass of Oxygen = O2 = 16 x 2 = 32g.
Gram molecular mass of a compound :- is its molecular mass expressed in
grams.
Eg :- Gram molecular mass of water = H2O = 1 x 2 + 16 = 2 + 16 = 18g.
Relationship between number of moles (n), mass (m), molar mass (M), Number
of atoms or molecules (N), and Avagadro number (NO).
m N m
n = ---- , n = ---- , m = n x N , M = ---
M NO n