Nitrogen combines with oxygen to generate nitrogen oxides in a variety of forms. Its oxides have distinct oxidation states, ranging from +1 to +5. Nitrogen oxides with a greater oxidation state are more acidic than those with a lower oxidation state.
Nitrogen Oxides are a combination of gases that include both nitrogen and oxygen. Nitric oxide (NO) and nitrogen dioxide (NO2) are two of the most toxicologically important chemicals. Nitrogen monoxide (or nitrous oxide, N2O) and nitrogen pentoxide are two more gases in this category (NO5).
The following are examples of nitrogen oxides:
Name of the Oxides of Nitrogen
Formula
Oxidation state of Nitrogen
Physical Appearance and Chemical Nature
Dinitrogen Oxide
N2O
+1
Colourless gas, neutral
Nitrogen monoxide
NO
+2
Colourless gas, neutral
Dinitrogen trioxide
N2O3
+3
Blue solid, acidic
Nitrogen dioxide
NO2
+4
Brown gas, acidic
Dinitrogen tetroxide
N2O4
+4
Colourless solid/liquid, acidic
Dinitrogen Pentoxide
N2O5
+5
Colourless solid, acidic
Table of Contents
Nitrogen Dioxide (NO2)
NO2 is the chemical name for Nitrogen dioxide, a highly poisonous gas. Nitrogen (IV) oxide of nitrogen is another name for it. It is a major atmospheric pollutant that absorbs UV light and prevents it from reaching the earth’s surface. Nitrogen (IV) oxide is a yellowish-brown liquid or a reddish-brown gas in its compressed form. When compared to air, its vapours are heavier.
Sources of Nitrogen dioxide
Over 98 % of man-made nitrogen emissions are caused by combustion, with the majority originating from stationary sources. Combustion-generated nitrogen oxides are primarily emitted as nitric oxide, a relatively harmless gas that is rapidly converted in the atmosphere to toxic nitrogen dioxide. Nitrogen dioxide is a detriment to human respiratory functions, and prolonged exposure can lead to an increase in the occurrence of respiratory ailments. Nitrogen dioxide is also a precursor in the formation of nitrate aerosols and nitrosamines, both of which are being studied for their potential health effects.
Uses of NO2
In the production of nitric acid, nitrogen dioxide is produced as a byproduct.
It is used in the production of oxidised cellulose compounds.
As a catalyst, it is used.
As an intermediate in the synthesis of sulphuric acid.
It is used as an oxidizer in rocket fuels.
It’s a nitrating agent.
It is used to bleach flour.
As an oxidising agent, it is used.
Used in the manufacture of explosives.
Health Hazards of NO2
Severe nitrogen deutoxide exposure can be fatal. When it comes into contact with it, it causes a burning sensation in the eyes and on the skin. It causes frostbite when it is liquid. It has been reported that it reacts with the blood to form methemoglobin. When heated to decompose, it emits toxic nitrogen oxide fumes. At high concentrations, nitrogen dioxide is an irritant gas that causes inflammation of the airways. NO2 primarily affects respiratory conditions that cause severe airway inflammation. Long-term exposure reduces lung capacity, increases the likelihood of respiratory problems, and heightens allergy response. NO2 also contributes to the formation of small particles (PM) and ozone at ground level, both of which have negative environmental consequences.
Nitric Acid (HNO3)
Nitric acid, with the chemical formula HNO3, is a strong acid. It’s also referred to as the spirit of nitre and aqua fortis. It is colourless in its pure form, but as it ages, it takes on a yellow cast. This colour is produced by the decomposition of nitric acid into nitrogen oxides and water. It’s extremely corrosive and toxic. It burns the skin severely. When it reacts with hydroxides, metals, and oxides, it generates nitrate salts.
HNO3 is a powerful oxidizing agent. It can be produced through the catalytic oxidation of ammonia. It is a common reagent used in laboratories as well as an important chemical used in the production of explosives and fertilizers.
Structure of HNO3 Molecules
Nitric acid molecules are made up of three oxygen atoms, one nitrogen atom, and one hydrogen atom. One of the oxygen atoms in HNO3 molecules is doubly bonded to the central nitrogen atom. Another oxygen atom is singly bonded to the central nitrogen atom as well as to a hydrogen atom. The nitric acid molecule’s final oxygen atom has a charge of -1 and is singly bonded to the central nitrogen atom. Because the nitrogen atom in the molecule’s centre is involved in four covalent bonds (with three oxygen atoms), it has a charge of +1. As a result, the net charge on the nitric acid molecule is zero (the positive charge on the nitrogen atom and the negative charge on the oxygen atom cancel each other out). It should be noted that the charges in these molecules can become delocalized as a result of resonance.
Laboratory Preparation of Nitric Acid
A less volatile acid can displace a more volatile acid from its salt. This is the fundamental principle underlying the laboratory preparation of nitric acid. Nitric acid, which is more volatile than sulphuric acid, is displaced from metal nitrates by sulphuric acid. In a round bottom flask, combine 50gm potassium nitrate (KNO3) and 25ml concentrated sulfuric acid (H2SO4). The reactants are heated to around 200 degrees Celsius, being careful not to exceed this temperature.
KNO3 + H2SO4 → KHSO4 + HNO3
Properties of Nitric Acid
Nitric acid is a very strong acid that causes blue litmus to turn red.
On standing, nitric acid decomposes to form brown nitrogen dioxide. This is why it turns brownish over time, despite the fact that fresh nitric acid is colourless.
Nitric acid reacts with metals above hydrogen in the metal activity series to produce hydrogen gas.
Uses of Nitric Acid
It is used to make ammonium nitrates, which are then used to make plastic, dye, and fertilizers.
It is used in the production of explosives such as TNT.
It is used as an oxidizer in liquid-fueled rockets.
It is used to remove warts in their purest form.
It is used in electrochemistry as a chemical doping agent.
Nitrous Oxide (N2O)
Nitrous oxide (N2O), generally known as laughing gas, is a regularly used anaesthetic and so has a wide range of medical applications. At room temperature, this organic molecule is colourless and non-flammable. It’s also known as laughing gas or nitrous oxide.
Properties of Nitrous Oxide (N2O)
This chemical is insoluble in water and, at higher temperatures, acts as a potent oxidant.
It smells slightly pleasant and appears as a colourless gas.
It produces exhilaration and hilarity when inhaled in little amounts.
It is the world’s most used inhaled anaesthetic because it relieves pain quickly.
At greater doses, it can have a narcotic effect and cause death by suffocation.
Preparation of Nitrous Oxide (N2O)
Nitrous oxide is always produced from ammonia nitrate. The cleanliness of the salt must be considered since it should not contain any hydrochlorate or ammonia.
It is made by mixing pounded ammonia carbonate with pure nitric acid, which has been diluted with half its volume of water so long as there is effervescence and a tiny amount of carbonate is left in the liquor at the end.
The solution has concentrated to the point that its boiling point exceeds 250 degrees Celsius and a drop of it solidifies on a cool glass plate
To produce nitrous oxide, a quantity of this salt is placed in a retort and heated with a charcoal coffee, the diffused heat of which is preferable to the heat of the lamp.
The salt boils at a temperature of fewer than 340 degrees Celsius and begins to decompose, releasing nitrous oxide and water.
Because cold water absorbs much of this gas, nitrous oxide should be collected in a gasometer or a gas holder filled with water that is about 90 degrees. The entire salt decomposes in the same way, and nothing is left in the retort.
Nitrous oxide is also created when the salt nitrogen sulphate of ammonia is dissolved in weak nitric acid, however, the following steps do not provide the gas in a pure state.
Uses of Nitrous Oxide (N2O)
As an oxidizer, it is utilised in rocket motors.
It’s used as a food ingredient and as a propellant for aerosol sprays.
It’s a material utilised in the production of semiconductors.
It is used as an analgesic and anaesthetic in medicine.
It is employed as a flavouring agent.
It is used as a fuel additive in motorsports.
It’s a dental filling.
It is used in the production of chemicals.
It’s a surgical instrument.
Nitric oxide (NO)
Nitric oxide, also known as NO, is a colourless gas.
It is one of the most important nitrogen oxides. Nitric oxide is a free radical, meaning it contains an unpaired electron. Nitric oxide is also a heteronuclear diatomic molecule, a type of molecule studied in the early modern period that gave rise to theories of chemical bonding.
Preparation of Nitric oxide (NO)
In the Ostwald process, nitric oxide is produced commercially by oxidizing ammonia at 750–900 °C with platinum as a catalyst:
4NH3 + 5O2 → 4NO + 6H2O
Commercially, nitric oxide is produced by oxidizing ammonia at 750–900 °C with platinum as a catalyst in the Ostwald process:
N2 + O2 → 2NO
Sample Questions (FAQs)
Question 1: What does nitric acid taste like?
Answer:
Nitric acid is a strong acid with acidic properties. A pH of less than 7, a bitter taste, and sometimes a violent reaction to other metals are examples of such properties. HNO3 is the chemical formula for nitric acid. Nitric acid is a colourless, white liquid that is extremely corrosive.
Question 2: What metals will nitric acid dissolve?
Answer:
Nitric acid oxidises some metals and alloys; however, gold and platinum are not oxidised when struck by concentrated nitric acid, and certain metals are passivated. These metals can be dissolved using an acid mixture or a dilute nitric solution.
Question 3: What does nitrogen dioxide do?
Answer:
The main effect of breathing in high levels of nitrogen dioxide is an increased risk of respiratory disorders. Nitrogen dioxide irritates the lungs’ lining, lowering immunity to lung infections. Wheezing, coughing, colds, pneumonia, and bronchitis can all result from this.
Question 4: Does nitrogen dioxide cause global warming?
Answer:
The two most toxic and dangerous nitrogen oxides are nitric oxide and nitrogen dioxide. Nitrous oxide, also known as “laughing gas,” is a greenhouse gas that contributes to global warming.
Question 5: Is nitrogen dioxide heavier than air?
Answer:
Nitric oxide is quickly oxidised in the air at high concentrations to produce nitrogen dioxide. Expositions. Because nitrogen dioxide is heavier than air, it can cause asphyxiation in poorly ventilated, sealed, or low-lying areas. At room temperature, the gases are nitrogen dioxide and nitric oxide.
Neeraj Anand, Param Anand
Er. Neeraj K.Anand is a freelance mentor and writer who specializes in Engineering & Science subjects. Neeraj Anand received a B.Tech degree in Electronics and Communication Engineering from N.I.T Warangal & M.Tech Post Graduation from IETE, New Delhi. He has over 30 years of teaching experience and serves as the Head of Department of ANAND CLASSES. He concentrated all his energy and experiences in academics and subsequently grew up as one of the best mentors in the country for students aspiring for success in competitive examinations.
In parallel, he started a Technical Publication "ANAND TECHNICAL PUBLISHERS" in 2002 and Educational Newspaper "NATIONAL EDUCATION NEWS" in 2014 at Jalandhar. Now he is a Director of leading publication "ANAND TECHNICAL PUBLISHERS", "ANAND CLASSES" and "NATIONAL EDUCATION NEWS".
He has published more than hundred books in the field of Physics, Mathematics, Computers and Information Technology. Besides this he has written many books to help students prepare for IIT-JEE and AIPMT entrance exams. He is an executive member of the IEEE (Institute of Electrical & Electronics Engineers. USA) and honorary member of many Indian scientific societies such as Institution of Electronics & Telecommunication Engineers, Aeronautical Society of India, Bioinformatics Institute of India, Institution of Engineers. He has got award from American Biographical Institute Board of International Research in the year 2005.
CBSE Class 11 Chemistry Syllabus is a vast which needs a clear understanding of the concepts and topics. Knowing CBSE Class 11 Chemistry syllabus helps students to understand the course structure of Chemistry.
Unit-wise CBSE Class 11 Syllabus for Chemistry
Below is a list of detailed information on each unit for Class 11 Students.
UNIT I – Some Basic Concepts of Chemistry
General Introduction: Importance and scope of Chemistry.
Nature of matter, laws of chemical combination, Dalton’s atomic theory: concept of elements, atoms and molecules.
Atomic and molecular masses, mole concept and molar mass, percentage composition, empirical and molecular formula, chemical reactions, stoichiometry and calculations based on stoichiometry.
UNIT II – Structure of Atom
Discovery of Electron, Proton and Neutron, atomic number, isotopes and isobars. Thomson’s model and its limitations. Rutherford’s model and its limitations, Bohr’s model and its limitations, concept of shells and subshells, dual nature of matter and light, de Broglie’s relationship, Heisenberg uncertainty principle, concept of orbitals, quantum numbers, shapes of s, p and d orbitals, rules for filling electrons in orbitals – Aufbau principle, Pauli’s exclusion principle and Hund’s rule, electronic configuration of atoms, stability of half-filled and completely filled orbitals.
UNIT III – Classification of Elements and Periodicity in Properties
Significance of classification, brief history of the development of periodic table, modern periodic law and the present form of periodic table, periodic trends in properties of elements -atomic radii, ionic radii, inert gas radii, Ionization enthalpy, electron gain enthalpy, electronegativity, valency. Nomenclature of elements with atomic number greater than 100.
UNIT IV – Chemical Bonding and Molecular Structure
Valence electrons, ionic bond, covalent bond, bond parameters, Lewis structure, polar character of covalent bond, covalent character of ionic bond, valence bond theory, resonance, geometry of covalent molecules, VSEPR theory, concept of hybridization, involving s, p and d orbitals and shapes of some simple molecules, molecular orbital theory of homonuclear diatomic molecules(qualitative idea only), Hydrogen bond.
UNIT V – Chemical Thermodynamics
Concepts of System and types of systems, surroundings, work, heat, energy, extensive and intensive properties, state functions. First law of thermodynamics – internal energy and enthalpy, measurement of U and H, Hess’s law of constant heat summation, enthalpy of bond dissociation, combustion, formation, atomization, sublimation, phase transition, ionization, solution and dilution. Second law of Thermodynamics (brief introduction) Introduction of entropy as a state function, Gibb’s energy change for spontaneous and nonspontaneous processes. Third law of thermodynamics (brief introduction).
UNIT VI – Equilibrium
Equilibrium in physical and chemical processes, dynamic nature of equilibrium, law of mass action, equilibrium constant, factors affecting equilibrium – Le Chatelier’s principle, ionic equilibrium- ionization of acids and bases, strong and weak electrolytes, degree of ionization, ionization of poly basic acids, acid strength, concept of pH, hydrolysis of salts (elementary idea), buffer solution, Henderson Equation, solubility product, common ion effect (with illustrative examples).
UNIT VII – Redox Reactions
Concept of oxidation and reduction, redox reactions, oxidation number, balancing redox reactions, in terms of loss and gain of electrons and change in oxidation number, applications of redox reactions.
UNIT VIII – Organic Chemistry: Some basic Principles and Techniques
General introduction, classification and IUPAC nomenclature of organic compounds. Electronic displacements in a covalent bond: inductive effect, electromeric effect, resonance and hyper conjugation. Homolytic and heterolytic fission of a covalent bond: free radicals, carbocations, carbanions, electrophiles and nucleophiles, types of organic reactions.
UNIT IX – Hydrocarbons
Classification of Hydrocarbons Aliphatic Hydrocarbons: Alkanes – Nomenclature, isomerism, conformation (ethane only), physical properties, chemical reactions. Alkenes – Nomenclature, structure of double bond (ethene), geometrical isomerism, physical properties, methods of preparation, chemical reactions: addition of hydrogen, halogen, water, hydrogen halides (Markovnikov’s addition and peroxide effect), ozonolysis, oxidation, mechanism of electrophilic addition. Alkynes – Nomenclature, structure of triple bond (ethyne), physical properties, methods of preparation, chemical reactions: acidic character of alkynes, addition reaction of – hydrogen, halogens, hydrogen halides and water.
Aromatic Hydrocarbons:
Introduction, IUPAC nomenclature, benzene: resonance, aromaticity, chemical properties: mechanism of electrophilic substitution. Nitration, sulphonation, halogenation, Friedel Craft’s alkylation and acylation, directive influence of functional group in monosubstituted benzene. Carcinogenicity and toxicity.
To know the CBSE Syllabus for all the classes from 1 to 12, visit the Syllabus page of CBSE. Meanwhile, to get the Practical Syllabus of Class 11 Chemistry, read on to find out more about the syllabus and related information in this page.
CBSE Class 11 Chemistry Practical Syllabus with Marking Scheme
In Chemistry subject, practical also plays a vital role in improving their academic scores in the subject. The overall weightage of Chemistry practical mentioned in the CBSE Class 11 Chemistry syllabus is 30 marks. So, students must try their best to score well in practicals along with theory. It will help in increasing their overall academic score.
CBSE Class 11 Chemistry Practical Syllabus
The experiments will be conducted under the supervision of subject teacher. CBSE Chemistry Practicals is for 30 marks. This contribute to the overall practical marks for the subject.
The table below consists of evaluation scheme of practical exams.
Evaluation Scheme
Marks
Volumetric Analysis
08
Salt Analysis
08
Content Based Experiment
06
Project Work
04
Class record and viva
04
Total
30
CBSE Syllabus for Class 11 Chemistry Practical
Micro-chemical methods are available for several of the practical experiments. Wherever possible such techniques should be used.
A. Basic Laboratory Techniques 1. Cutting glass tube and glass rod 2. Bending a glass tube 3. Drawing out a glass jet 4. Boring a cork
B. Characterization and Purification of Chemical Substances 1. Determination of melting point of an organic compound. 2. Determination of boiling point of an organic compound. 3. Crystallization of impure sample of any one of the following: Alum, Copper Sulphate, Benzoic Acid.
C. Experiments based on pH
1. Any one of the following experiments:
Determination of pH of some solutions obtained from fruit juices, solution of known and varied concentrations of acids, bases and salts using pH paper or universal indicator.
Comparing the pH of solutions of strong and weak acids of same concentration.
Study the pH change in the titration of a strong base using universal indicator.
2. Study the pH change by common-ion in case of weak acids and weak bases.
D. Chemical Equilibrium One of the following experiments:
1. Study the shift in equilibrium between ferric ions and thiocyanate ions by increasing/decreasing the concentration of either of the ions. 2. Study the shift in equilibrium between [Co(H2O)6] 2+ and chloride ions by changing the concentration of either of the ions.
E. Quantitative Estimation i. Using a mechanical balance/electronic balance. ii. Preparation of standard solution of Oxalic acid. iii. Determination of strength of a given solution of Sodium hydroxide by titrating it against standard solution of Oxalic acid. iv. Preparation of standard solution of Sodium carbonate. v. Determination of strength of a given solution of hydrochloric acid by titrating it against standard Sodium Carbonatesolution.
F. Qualitative Analysis 1) Determination of one anion and one cation in a given salt Cations‐ Pb2+, Cu2+, As3+, Al3+, Fe3+, Mn2+, Ni2+, Zn2+, Co2+, Ca2+, Sr2+, Ba2+, Mg2+, NH4+ Anions – (CO3)2‐ , S2‐, NO2‐ , SO32‐, SO2‐ , NO ‐ , Cl‐ , Br‐, I‐, PO43‐ , C2O2‐ ,CH3COO‐ (Note: Insoluble salts excluded)
2) Detection of ‐ Nitrogen, Sulphur, Chlorine in organic compounds.
G) PROJECTS Scientific investigations involving laboratory testing and collecting information from other sources.
A few suggested projects are as follows:
Checking the bacterial contamination in drinking water by testing sulphide ion
Study of the methods of purification of water.
Testing the hardness, presence of Iron, Fluoride, Chloride, etc., depending upon the regional variation in drinking water and study of causes of presence of these ions above permissible limit (if any).
Investigation of the foaming capacity of different washing soaps and the effect of addition of Sodium carbonate on it.
Study the acidity of different samples of tea leaves.
Determination of the rate of evaporation of different liquids Study the effect of acids and bases on the tensile strength of fibres.
Study of acidity of fruit and vegetable juices.
Note: Any other investigatory project, which involves about 10 periods of work, can be chosen with theapproval of the teacher.
Practical Examination for Visually Impaired Students of Class 11
Below is a list of practicals for the visually impaired students.
A. List of apparatus for identification for assessment in practicals (All experiments) Beaker, tripod stand, wire gauze, glass rod, funnel, filter paper, Bunsen burner, test tube, test tube stand, dropper, test tube holder, ignition tube, china dish, tongs, standard flask, pipette, burette, conical flask, clamp stand, dropper, wash bottle • Odour detection in qualitative analysis • Procedure/Setup of the apparatus
B. List of Experiments A. Characterization and Purification of Chemical Substances 1. Crystallization of an impure sample of any one of the following: copper sulphate, benzoic acid B. Experiments based on pH 1. Determination of pH of some solutions obtained from fruit juices, solutions of known and varied concentrations of acids, bases and salts using pH paper 2. Comparing the pH of solutions of strong and weak acids of same concentration.
C. Chemical Equilibrium 1. Study the shift in equilibrium between ferric ions and thiocyanate ions by increasing/decreasing the concentration of eitherions. 2. Study the shift in equilibrium between [Co(H2O)6]2+ and chloride ions by changing the concentration of either of the ions.
D. Quantitative estimation 1. Preparation of standard solution of oxalic acid. 2. Determination of molarity of a given solution of sodium hydroxide by titrating it against standard solution of oxalic acid.
E. Qualitative Analysis 1. Determination of one anion and one cation in a given salt 2. Cations – NH+4 Anions – (CO3)2-, S2-, (SO3)2-, Cl-, CH3COO- (Note: insoluble salts excluded) 3. Detection of Nitrogen in the given organic compound. 4. Detection of Halogen in the given organic compound.
Note: The above practicals may be carried out in an experiential manner rather than recording observations.
We hope students must have found this information on CBSE Syllabus useful for their studying Chemistry. Learn Maths & Science in interactive and fun loving ways with ANAND CLASSES (A School Of Competitions) App/Tablet.
Frequently Asked Questions on CBSE Class 11 Chemistry Syllabus
Q1
How many units are in the CBSE Class 11 Chemistry Syllabus?
There are 9 units in the CBSE Class 11 Chemistry Syllabus. Students can access various study materials for the chapters mentioned in this article for free at ANAND CLASSES (A School Of Competitions).
Q2
What is the total marks for practicals examination as per the CBSE Class 11 Chemistry Syllabus?
The total marks for the practicals as per the CBSE Class 11 Chemistry Syllabus is 30. It includes volumetric analysis, content-based experiment, salt analysis, class record, project work and viva.
Q3
Which chapter carries more weightage as per the CBSE Syllabus for Class 11 Chemistry?
The organic chemistry chapter carries more weightage as per the CBSE Syllabus for Class 11 Chemistry.
Anand Technical Publishers
Buy Products (Printed Books & eBooks) of Anand Classes published by Anand Technical Publishers, Visit at following link :
