Amit Kumar, a class 12 student, thanks the principal, chemistry teacher, parents, and classmates for their support and guidance in completing his chemistry project on the analysis of alloys. The project involved qualitative analysis experiments to identify the components of brass and bronze samples. The brass sample was found to contain copper and zinc as the main constituents, while the bronze sample contained copper and tin as expected.
This document provides an acknowledgment and thanks to a chemistry teacher, Mr. Rakesh K., for his guidance and support in completing a school project. It expresses deep gratitude and obligation to the teacher for inspiring enthusiasm and instilling dynamism. The document then covers the topics of alloys, including common alloys like brass, bronze, and amalgam. It discusses the composition and properties of these alloys and includes examples like dental fillings and artisanal mining. An experiment section and bibliography are also included at the end.
Chemistry Investigatory project on "Study of constituents of an alloy"Swaroop Somanna
This is a CBSE class 12 Chemistry Investigatory Project on the topic "Study of constituents of an alloy".
THIS PROJECT HAS ALREADY BEEN SUBMITTED TO THE RESPECTIVE SCHOOL BY THE AUTHOR AND MUST NOT BE COPIED.
This project must only be used for idea gaining and reference purpose.
chemistry project on constituents of alloysMILANSOOD1
This document is a student's chemistry project on the study of alloy constituents. It consists of an introduction to alloys, examples of common alloys like brass and bronze, how alloys are prepared and analyzed. It also describes two experiments - qualitative analysis of a brass sample and qualitative analysis of a bronze sample. Both samples were found to contain their main constituents of copper and zinc for brass, and copper and tin for bronze. The project concludes with some uses of alloys.
This document summarizes several common metal alloys, including their typical compositions and common uses. It discusses amalgams, brass, bronze, pewter, and nickel silver. For each alloy, it provides the main metals used in the composition as well as some historical and current applications where the alloys are employed.
Chemistry project on study of constituents of alloyspranav1645
- The document is a chemistry project report submitted by Pranav Parashar analyzing the constituents of alloys.
- It includes an acknowledgement, index of sections, and sections on common alloys like brass and bronze, preparation of alloys, analysis of an alloy, two experiments conducted, and uses of alloys.
- The experiments involve qualitative analysis of samples of brass and bronze to identify the main metal constituents of copper and zinc in brass, and copper and tin in bronze.
Chemistry project-study of constituents of an alloy himanshu rawat
This document describes a chemistry project to analyze the constituents of two alloys - brass and bronze. The project aims to increase understanding of alloy analysis through hands-on experience. Specific objectives are to analyze the constituents of brass, which contains copper and zinc, and bronze, which contains copper and tin. The document outlines the required materials, relevant theory, procedure and observations for testing samples of each alloy to identify the present metals through formation of characteristic precipitates and color changes.
- The document is a chemistry project submitted by a student named Tarun Malhotra analyzing samples of brass and bronze through qualitative analysis.
- It thanks various teachers and administrators for their support and contains an index of sections including introductions to alloys, common alloys like brass and bronze, how to prepare alloys, and descriptions of the qualitative analysis experiments performed on samples of brass and bronze.
- The experiments aimed to identify the metal constituents in the samples through chemical tests to detect copper and zinc in brass and tests for copper and tin in bronze.
This document provides an acknowledgment and thanks to a chemistry teacher, Mr. Rakesh K., for his guidance and support in completing a school project. It expresses deep gratitude and obligation to the teacher for inspiring enthusiasm and instilling dynamism. The document then covers the topics of alloys, including common alloys like brass, bronze, and amalgam. It discusses the composition and properties of these alloys and includes examples like dental fillings and artisanal mining. An experiment section and bibliography are also included at the end.
Chemistry Investigatory project on "Study of constituents of an alloy"Swaroop Somanna
This is a CBSE class 12 Chemistry Investigatory Project on the topic "Study of constituents of an alloy".
THIS PROJECT HAS ALREADY BEEN SUBMITTED TO THE RESPECTIVE SCHOOL BY THE AUTHOR AND MUST NOT BE COPIED.
This project must only be used for idea gaining and reference purpose.
chemistry project on constituents of alloysMILANSOOD1
This document is a student's chemistry project on the study of alloy constituents. It consists of an introduction to alloys, examples of common alloys like brass and bronze, how alloys are prepared and analyzed. It also describes two experiments - qualitative analysis of a brass sample and qualitative analysis of a bronze sample. Both samples were found to contain their main constituents of copper and zinc for brass, and copper and tin for bronze. The project concludes with some uses of alloys.
This document summarizes several common metal alloys, including their typical compositions and common uses. It discusses amalgams, brass, bronze, pewter, and nickel silver. For each alloy, it provides the main metals used in the composition as well as some historical and current applications where the alloys are employed.
Chemistry project on study of constituents of alloyspranav1645
- The document is a chemistry project report submitted by Pranav Parashar analyzing the constituents of alloys.
- It includes an acknowledgement, index of sections, and sections on common alloys like brass and bronze, preparation of alloys, analysis of an alloy, two experiments conducted, and uses of alloys.
- The experiments involve qualitative analysis of samples of brass and bronze to identify the main metal constituents of copper and zinc in brass, and copper and tin in bronze.
Chemistry project-study of constituents of an alloy himanshu rawat
This document describes a chemistry project to analyze the constituents of two alloys - brass and bronze. The project aims to increase understanding of alloy analysis through hands-on experience. Specific objectives are to analyze the constituents of brass, which contains copper and zinc, and bronze, which contains copper and tin. The document outlines the required materials, relevant theory, procedure and observations for testing samples of each alloy to identify the present metals through formation of characteristic precipitates and color changes.
- The document is a chemistry project submitted by a student named Tarun Malhotra analyzing samples of brass and bronze through qualitative analysis.
- It thanks various teachers and administrators for their support and contains an index of sections including introductions to alloys, common alloys like brass and bronze, how to prepare alloys, and descriptions of the qualitative analysis experiments performed on samples of brass and bronze.
- The experiments aimed to identify the metal constituents in the samples through chemical tests to detect copper and zinc in brass and tests for copper and tin in bronze.
The document is an acknowledgement and introduction to a student project on the study of alloy constituents. It acknowledges the student's guide and others who provided support and encouragement. It provides an introduction to what an alloy is comprised of and some common alloys like brass, bronze, and duralumin along with their typical compositions. It also outlines the objectives of the project to qualitatively analyze the metals present in a sample alloy through experimentation.
The document describes experiments performed to identify an unknown inorganic salt. Key observations indicated the salt was blue in color and soluble in water. Tests confirmed the presence of copper cations and sulfate anions. Specifically, the salt produced a bluish-green flame, turned white when heated, and gave a white precipitate with barium chloride and dilute hydrochloric acid, identifying it as copper sulfate.
The document summarizes key information about d-block and f-block elements. It discusses:
- The d-block elements have their d orbitals progressively filled in each period, while the f-block elements have their 4f and 5f orbitals filled in the latter two periods.
- Transition metals exhibit a variety of oxidation states, melting points, atomic radii, and magnetic properties due to their incompletely filled d orbitals.
- Properties vary periodically across each series as the nuclear charge increases, with factors like ionization energies and electronegativity influencing stability and reactivity.
This document contains a dissertation submitted by Himanshu Kumar on the topic "Effect of Metal Coupling on Rusting of Iron". The 3-page summary includes an introduction, aim, materials, theory, procedure, observations, results, conclusions and bibliography. The student investigated how coupling different metals (iron, aluminum, brass and zinc) affects the rusting rate of iron in acidic and basic solutions. The results showed brass had the highest corrosion rate while aluminum had the lowest. In acidic solutions, iron coupled with aluminum corroded fastest while iron coupled with zinc corroded slowest. In basic solutions, the rates followed the order of brass coupled with aluminum corroding fastest and brass coupled with zinc corroding slowest. The conclusions
Ppt1 Introduction To Qa & Tests For Gasessitinurbaiyah
The document discusses qualitative analysis, which is a process chemists use to identify unknown substances. It involves performing chemical tests to determine the cations and anions present, allowing identification of the substance. Common tests include observing the appearance of solids and solutions, determining solubility, observing gases produced from heating or adding acids/alkalis. Gases can be identified using tests like their reaction with litmus, ability to relight a glowing splint, or forming precipitates with reagents. The goal is to perform experiments and make inferences to identify an unknown salt or mixture.
The meter bridge is an instrument used to measure unknown resistances based on the Wheatstone bridge principle. It consists of a 1 meter long wire of uniform cross-section attached to a wooden block, along with metal strips, a galvanometer, and a movable contact point called a jockey stick. To measure an unknown resistance, the meter bridge circuit is balanced by sliding the jockey stick along the wire until a null point is detected by the galvanometer. Using the length at the balance point, the formula R=X(l/(100-l)) can be used to calculate the unknown resistance R based on the known standard resistance X.
Chemistry class 12 project on study of Constituents of AlloyHarsh Kumar
Harsh Kumar submitted a chemistry project on analyzing the constituents of alloys. He thanked his teacher, principal, parents, and friends for their support and guidance. The project included an introduction to alloys like brass, bronze, and duralumin. It described how to prepare and analyze alloys. The experiment involved qualitatively analyzing a bronze sample by dissolving it in nitric acid and testing the solution to identify copper and tin.
CBSE Class 12 Chemistry Chapter 3 (Electrochemistry) | Homi InstituteHomi Institute
1. Electrochemistry is the study of chemical processes involving the movement of electrons, which can generate electricity through oxidation-reduction reactions.
2. A salt bridge is a device used in electrochemical cells to connect the half cells and maintain electrical neutrality, preventing the accumulation of charges that would stop the reaction.
3. Common reference electrodes include the standard hydrogen electrode and silver-silver chloride electrode, but the standard hydrogen electrode is difficult to assemble and maintain precisely.
Qualitative analysis is used to identify substances present in a mixture without determining quantities. Salts can be identified by their physical and chemical properties like color and solubility. Various tests are used to identify cations like Group I and II metals that form white precipitates with sodium hydroxide, and anions like carbonates from effervescence with acid and chloride with silver nitrate precipitation. Color changes also indicate ions present like blue for copper and green/brown for iron.
These are the class 12 practicals held in cbse schools and it contains all the inorganic and organic salt tests in a simplified way and all the other experiments
The document discusses the hard and soft acid and base (HSAB) theory introduced by Pearson in 1963. It explains that hard acids prefer to coordinate with hard bases, and soft acids prefer soft bases, due to their relative polarizabilities. Hard acids and bases are less polarizable, while soft species are more polarizable and form stronger bonds through electron sharing. The HSAB concept is used to understand stability, reactions, and reaction mechanisms based on qualitative descriptions of predominant factors like polarizability.
The document discusses the lanthanide series of f-block elements. It provides the electronic configurations of the lanthanide elements from Lanthanum to Lutetium. It describes the lanthanide contraction effect where atomic and ionic radii decrease across the series. Key effects of lanthanide contraction include decreased basicity and similar ionic radii of post-lanthanide elements to those in the previous period. The document also briefly introduces the actinide series and notes their similar properties to lanthanides but with 5f electrons instead of 4f.
• Corrosion is a serious problem of some metal like iron, zinc, aluminium and alloys like brass which are commonly used in day to day life.
• Apart from reducing the life of articles made up of these metals or alloys the chemical substances formed out of corrosion have serious public health problems.
• Replacement of machines or their parts and many other articles in industrial and public dealing lead to huge expenditure.
• Hence, how to reduce or avoid corrosion of articles made up of metals or alloys has been a major subject in field of chemistry and electro-chemistry.
(1) A student conducted an experiment to test for the presence of oxalate ions in raw, semi-ripe, and ripe guava samples.
(2) Oxalate ions were extracted from crushed guava pulp and titrated against a potassium permanganate solution.
(3) The results showed that the concentration of oxalate ions increased with the ripening of the guava, from 0.58 g/L in raw guava to 0.61 g/L in ripe guava.
1. Coordinate compounds are complexes where a central metal ion is coordinated to surrounding ligands. Coordination compounds can be ionic or molecular and the ligands are attached to the central ion via coordinate bonds.
2. The ligands directly attached to the central metal ion make up its coordination sphere. The total number of ligands is the coordination number. Bidentate and tridentate ligands that attach at multiple points contribute more than one to the coordination number.
3. Coordinate compounds can exhibit several types of isomerism including ionization isomerism from interchange of ligands and ions, coordination isomerism from interchange of complex ions, and geometrical isomerism from different spatial arrangements of ligands.
The document discusses the physical and chemical properties of alkali metals and alkaline earth metals. It provides details about their ionization energies, reactivity, reactions with water and other substances, and color imparted to flames. Alkali metals have low melting points due to weak metallic bonding. Their reactivity increases down the group as ionization energy decreases. Alkaline earth metals have higher melting points than alkali metals due to smaller atomic size and stronger metallic bonds. Their reactivity is also less than alkali metals.
This document describes a chemistry project investigating the presence of oxalate ions in guava fruit at different stages of ripening. The project involves extracting oxalate ions from guava pulp using dilute sulfuric acid and then titrating the solution with potassium permanganate. Observations recorded the volume of potassium permanganate needed to reach the endpoint for fresh, semi-ripened, and ripened guava. Calculations determined the strength of oxalate ions increased with ripening from 0.58 g/L for fresh guava to 0.61 g/L for ripened guava. The conclusions were that the content of oxalate ions in guava was close to literature values and increased with the fruit's ripening
This document lists the appearances of various chemical powders and solids. It describes 18 different chemicals including metals like zinc, lead, cadmium, iron, copper and aluminum as well as their oxides. For each chemical, it provides the chemical name and describes its visual appearance such as color and physical state as either a powder, crystal or solid metal.
Chapter 12 aldehydes ketones and carboxylic_acidssuresh gdvm
This document contains sample questions and answers about aldehydes, ketones, and carboxylic acids from Class XII Chemistry Chapter 12. The questions cover defining and giving examples of reaction types, naming compounds using IUPAC nomenclature, drawing structures of derivatives, predicting reaction products, and converting between related compounds.
This document discusses Cadbury's products, prices, places of production and sale, and methods of promotion. It lists some of Cadbury's popular products like Dairy Milk, Celebrations, Bournvita, and Oreo cookies. It notes that Cadbury offers convenient pricing for all products and that price is a factor in consumer purchases. It also describes that Cadbury produces chocolate in Birmingham and sells to shops worldwide, exporting to over 200 countries. Finally, it outlines Cadbury's promotional strategies through television, print media, posters, and taglines to attract customers.
The document outlines an online law bookstore project that aims to create a digital platform for customers to directly purchase books in real-time without intermediaries. It describes problems with existing manual systems being time-consuming and labor-intensive with a lack of coordination. The goals of the new system are to maximize search options by author, book title, and subject while providing book reading facilities, delivery to customers' doors, and time savings. It will include administrative modules to manage book and order details and user modules for registration, login, address updates, book searches, notifications, and feedback.
The document is an acknowledgement and introduction to a student project on the study of alloy constituents. It acknowledges the student's guide and others who provided support and encouragement. It provides an introduction to what an alloy is comprised of and some common alloys like brass, bronze, and duralumin along with their typical compositions. It also outlines the objectives of the project to qualitatively analyze the metals present in a sample alloy through experimentation.
The document describes experiments performed to identify an unknown inorganic salt. Key observations indicated the salt was blue in color and soluble in water. Tests confirmed the presence of copper cations and sulfate anions. Specifically, the salt produced a bluish-green flame, turned white when heated, and gave a white precipitate with barium chloride and dilute hydrochloric acid, identifying it as copper sulfate.
The document summarizes key information about d-block and f-block elements. It discusses:
- The d-block elements have their d orbitals progressively filled in each period, while the f-block elements have their 4f and 5f orbitals filled in the latter two periods.
- Transition metals exhibit a variety of oxidation states, melting points, atomic radii, and magnetic properties due to their incompletely filled d orbitals.
- Properties vary periodically across each series as the nuclear charge increases, with factors like ionization energies and electronegativity influencing stability and reactivity.
This document contains a dissertation submitted by Himanshu Kumar on the topic "Effect of Metal Coupling on Rusting of Iron". The 3-page summary includes an introduction, aim, materials, theory, procedure, observations, results, conclusions and bibliography. The student investigated how coupling different metals (iron, aluminum, brass and zinc) affects the rusting rate of iron in acidic and basic solutions. The results showed brass had the highest corrosion rate while aluminum had the lowest. In acidic solutions, iron coupled with aluminum corroded fastest while iron coupled with zinc corroded slowest. In basic solutions, the rates followed the order of brass coupled with aluminum corroding fastest and brass coupled with zinc corroding slowest. The conclusions
Ppt1 Introduction To Qa & Tests For Gasessitinurbaiyah
The document discusses qualitative analysis, which is a process chemists use to identify unknown substances. It involves performing chemical tests to determine the cations and anions present, allowing identification of the substance. Common tests include observing the appearance of solids and solutions, determining solubility, observing gases produced from heating or adding acids/alkalis. Gases can be identified using tests like their reaction with litmus, ability to relight a glowing splint, or forming precipitates with reagents. The goal is to perform experiments and make inferences to identify an unknown salt or mixture.
The meter bridge is an instrument used to measure unknown resistances based on the Wheatstone bridge principle. It consists of a 1 meter long wire of uniform cross-section attached to a wooden block, along with metal strips, a galvanometer, and a movable contact point called a jockey stick. To measure an unknown resistance, the meter bridge circuit is balanced by sliding the jockey stick along the wire until a null point is detected by the galvanometer. Using the length at the balance point, the formula R=X(l/(100-l)) can be used to calculate the unknown resistance R based on the known standard resistance X.
Chemistry class 12 project on study of Constituents of AlloyHarsh Kumar
Harsh Kumar submitted a chemistry project on analyzing the constituents of alloys. He thanked his teacher, principal, parents, and friends for their support and guidance. The project included an introduction to alloys like brass, bronze, and duralumin. It described how to prepare and analyze alloys. The experiment involved qualitatively analyzing a bronze sample by dissolving it in nitric acid and testing the solution to identify copper and tin.
CBSE Class 12 Chemistry Chapter 3 (Electrochemistry) | Homi InstituteHomi Institute
1. Electrochemistry is the study of chemical processes involving the movement of electrons, which can generate electricity through oxidation-reduction reactions.
2. A salt bridge is a device used in electrochemical cells to connect the half cells and maintain electrical neutrality, preventing the accumulation of charges that would stop the reaction.
3. Common reference electrodes include the standard hydrogen electrode and silver-silver chloride electrode, but the standard hydrogen electrode is difficult to assemble and maintain precisely.
Qualitative analysis is used to identify substances present in a mixture without determining quantities. Salts can be identified by their physical and chemical properties like color and solubility. Various tests are used to identify cations like Group I and II metals that form white precipitates with sodium hydroxide, and anions like carbonates from effervescence with acid and chloride with silver nitrate precipitation. Color changes also indicate ions present like blue for copper and green/brown for iron.
These are the class 12 practicals held in cbse schools and it contains all the inorganic and organic salt tests in a simplified way and all the other experiments
The document discusses the hard and soft acid and base (HSAB) theory introduced by Pearson in 1963. It explains that hard acids prefer to coordinate with hard bases, and soft acids prefer soft bases, due to their relative polarizabilities. Hard acids and bases are less polarizable, while soft species are more polarizable and form stronger bonds through electron sharing. The HSAB concept is used to understand stability, reactions, and reaction mechanisms based on qualitative descriptions of predominant factors like polarizability.
The document discusses the lanthanide series of f-block elements. It provides the electronic configurations of the lanthanide elements from Lanthanum to Lutetium. It describes the lanthanide contraction effect where atomic and ionic radii decrease across the series. Key effects of lanthanide contraction include decreased basicity and similar ionic radii of post-lanthanide elements to those in the previous period. The document also briefly introduces the actinide series and notes their similar properties to lanthanides but with 5f electrons instead of 4f.
• Corrosion is a serious problem of some metal like iron, zinc, aluminium and alloys like brass which are commonly used in day to day life.
• Apart from reducing the life of articles made up of these metals or alloys the chemical substances formed out of corrosion have serious public health problems.
• Replacement of machines or their parts and many other articles in industrial and public dealing lead to huge expenditure.
• Hence, how to reduce or avoid corrosion of articles made up of metals or alloys has been a major subject in field of chemistry and electro-chemistry.
(1) A student conducted an experiment to test for the presence of oxalate ions in raw, semi-ripe, and ripe guava samples.
(2) Oxalate ions were extracted from crushed guava pulp and titrated against a potassium permanganate solution.
(3) The results showed that the concentration of oxalate ions increased with the ripening of the guava, from 0.58 g/L in raw guava to 0.61 g/L in ripe guava.
1. Coordinate compounds are complexes where a central metal ion is coordinated to surrounding ligands. Coordination compounds can be ionic or molecular and the ligands are attached to the central ion via coordinate bonds.
2. The ligands directly attached to the central metal ion make up its coordination sphere. The total number of ligands is the coordination number. Bidentate and tridentate ligands that attach at multiple points contribute more than one to the coordination number.
3. Coordinate compounds can exhibit several types of isomerism including ionization isomerism from interchange of ligands and ions, coordination isomerism from interchange of complex ions, and geometrical isomerism from different spatial arrangements of ligands.
The document discusses the physical and chemical properties of alkali metals and alkaline earth metals. It provides details about their ionization energies, reactivity, reactions with water and other substances, and color imparted to flames. Alkali metals have low melting points due to weak metallic bonding. Their reactivity increases down the group as ionization energy decreases. Alkaline earth metals have higher melting points than alkali metals due to smaller atomic size and stronger metallic bonds. Their reactivity is also less than alkali metals.
This document describes a chemistry project investigating the presence of oxalate ions in guava fruit at different stages of ripening. The project involves extracting oxalate ions from guava pulp using dilute sulfuric acid and then titrating the solution with potassium permanganate. Observations recorded the volume of potassium permanganate needed to reach the endpoint for fresh, semi-ripened, and ripened guava. Calculations determined the strength of oxalate ions increased with ripening from 0.58 g/L for fresh guava to 0.61 g/L for ripened guava. The conclusions were that the content of oxalate ions in guava was close to literature values and increased with the fruit's ripening
This document lists the appearances of various chemical powders and solids. It describes 18 different chemicals including metals like zinc, lead, cadmium, iron, copper and aluminum as well as their oxides. For each chemical, it provides the chemical name and describes its visual appearance such as color and physical state as either a powder, crystal or solid metal.
Chapter 12 aldehydes ketones and carboxylic_acidssuresh gdvm
This document contains sample questions and answers about aldehydes, ketones, and carboxylic acids from Class XII Chemistry Chapter 12. The questions cover defining and giving examples of reaction types, naming compounds using IUPAC nomenclature, drawing structures of derivatives, predicting reaction products, and converting between related compounds.
This document discusses Cadbury's products, prices, places of production and sale, and methods of promotion. It lists some of Cadbury's popular products like Dairy Milk, Celebrations, Bournvita, and Oreo cookies. It notes that Cadbury offers convenient pricing for all products and that price is a factor in consumer purchases. It also describes that Cadbury produces chocolate in Birmingham and sells to shops worldwide, exporting to over 200 countries. Finally, it outlines Cadbury's promotional strategies through television, print media, posters, and taglines to attract customers.
The document outlines an online law bookstore project that aims to create a digital platform for customers to directly purchase books in real-time without intermediaries. It describes problems with existing manual systems being time-consuming and labor-intensive with a lack of coordination. The goals of the new system are to maximize search options by author, book title, and subject while providing book reading facilities, delivery to customers' doors, and time savings. It will include administrative modules to manage book and order details and user modules for registration, login, address updates, book searches, notifications, and feedback.
This document contains the resume of S. Ghousullah. It summarizes his contact information, career objective, skills, qualifications, work experience and technical skills. Ghousullah has over 5 years of experience as an electrical engineer, working on projects involving PLC, SCADA, HMI, electrical design and automation. He is proficient in AutoCAD Electrical, various PLC platforms including Allen Bradley, Siemens and has experience conducting energy audits and setting up motor testing labs.
This document defines probable maximum loss (PML) and discusses its application. PML is defined as an estimate of the maximum monetary loss insurers could experience from a single event at a insured location. The document outlines the elements used to calculate PML, including construction type, occupancy, protection systems, and exposures. It provides examples of applying PML guidelines to different asset classes and construction types. While PML is useful for underwriters, the document notes it requires judgment and care, as actual losses could exceed estimates if PML is assessed too low.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise boosts blood flow and levels of serotonin and endorphins which elevate mood and may help prevent mental illness.
This document discusses cyber liability insurance. It begins by defining cyber risk as any risk of financial loss, disruption, or damage to an organization's reputation from a failure of its information technology systems. It then discusses the types of damages that can occur, including non-physical damages like data corruption or theft and physical damages like system manipulation. It notes that all companies have cyber risk. It discusses how industries like energy are particularly exposed to risks like power grid hacking. The document outlines common insurable cyber risks, underwriting considerations for pricing cyber policies, and ways organizations can manage their cyber risks.
1) Epítopo é a menor parte de um antígeno capaz de estimular resposta imunológica. Epigenética engloba modificações hereditárias do DNA que alteram expressão gênica sem mudar sequências. A teoria do conflito se baseia no conflito de interesses entre pais em relação à prole.
Un transformador permite aumentar o disminuir el voltaje en un circuito eléctrico de corriente alterna manteniendo la frecuencia, y está compuesto por un núcleo de hierro con bobinas primarias y secundarias. Un motor eléctrico transforma energía eléctrica en mecánica a través de interacciones electromagnéticas, y algunos pueden funcionar también como generadores. Un generador eléctrico transforma energía mecánica en eléctrica mediante la acción de un campo magnético sobre conductores elé
A Winter Project Report on Production Department Analysis of "Italia Ceramics...Bhavik Parmar
The ceramic tile industry has experienced global growth and transformation. While consumption declined in advanced western economies during the 2009 financial crisis, consumption in Asia, the Gulf region, Latin America, and North Africa continued to grow strongly. Within regions, consumption varied between neighboring countries. Today, ceramic tile production is highly automated and used widely in residential and commercial buildings globally due to its durability and aesthetic appeal. Ceramic tiles have become accessible for most consumers.
El documento describe diferentes tipos de ensayos, incluyendo ensayos argumentativos, científicos y literarios. Explica que los argumentos son la parte más importante de todo ensayo y que no hay reglas estrictas para escribir uno, permitiendo al autor desarrollar el tema de manera libre y personal.
Project report on just in time productionProjects Kart
This document provides background information on Cipla Ltd., an Indian pharmaceutical company. It details the company's history, including being founded in 1935 by Khwaja Abdul Hamied in Mumbai. Cipla aided India during World War 2 by providing essential medicines when supplies were low. The company has grown to be a global leader in generic drugs and exports to many countries. It operates manufacturing facilities approved by regulatory bodies in the US, UK, Australia, South Africa and other nations. Cipla continues to grow and develop new drugs, helping address healthcare needs around the world.
Implementing OpenID for Your Social Networking SiteDavid Keener
There are thousands of social networking sites, each with their own unique sign-on systems. How many user names and passwords do you really want to remember? Wouldn't it be nice if you could have a single sign-on that you could use on all of the sites that you frequent? OpenID is an open-source, decentralized sign-on technology that promises this and more. Find out how to implement OpenID for a web site using Ruby on Rails.
Southeast Asia's Top 75 FinTech Startups ReportTechsauce Media
The document provides an overview of the top 75 fintech companies in Southeast Asia in 2017. It begins with an introduction to fintech trends in the region and outlines the selection criteria used to identify the top companies. The selection criteria focused on total capital raised, business expansion to other countries, and being a market leader or having a innovative business model. It then provides breakdowns of fintech company densities by country and category. The remainder of the document consists of profiles for each of the top 75 fintech companies, providing details on each company's business model, investments, and operating countries.
Uma turma de crianças pequenas realizou várias experiências para entender por que o gelo derrete. Eles descobriram que o gelo derrete quando está quente, iluminado ou em movimento, mas permanece sólido no congelador. As crianças celebraram estas descobertas fazendo pinturas com gelo colorido e assistindo ao filme Frozen.
10 Ways Your Boss Kills Employee MotivationOfficevibe
This document outlines 10 ways that bosses can kill employee motivation, including micromanaging employees, focusing only on mistakes, dismissing new ideas, holding useless meetings, making empty promises, telling inappropriate jokes, not keeping their word, measuring employee success in the wrong way, setting unrealistic deadlines, and playing favorites. The document encourages bosses to listen to employee concerns to better motivate them.
Recovery: Job Growth and Education Requirements Through 2020CEW Georgetown
Recovery: Job Growth and Education Requirements Through 2020: Projections of jobs and education requirements through 2020. This report shows where the jobs will be by education level, occupation and industry. Recovery 2020 is an update to our Help Wanted: Projections of Jobs and Education Requirements Through 2018.
The document is a student's project report on analyzing alloys. It thanks various teachers and classmates for their support and guidance. It provides background on alloys such as brass, bronze, and amalgam. It describes the process of preparing alloys and qualitatively analyzing samples of brass and bronze. The objectives are to identify the metals in samples of brass and bronze using chemical tests and reagents. Qualitative analysis identifies copper and zinc in brass and copper and tin in bronze.
This document discusses casting alloys used in dentistry. It begins with a brief history of casting alloys and their evolution since the 1900s. It then covers the key properties casting alloys must have including biocompatibility, corrosion resistance, hardness, castability and bonding to ceramics. The document classifies casting alloys and discusses commonly used types such as gold alloys, silver-palladium alloys, cobalt-chrome alloys and titanium alloys. It provides details on the composition and characteristics of different alloy groups.
Copper and its alloys are classified according to the Copper Development Association. Wrought alloys include unalloyed copper, brass, and bronze. Unalloyed copper includes electrolytic tough-pitch copper, oxygen-free copper, and phosphorus deoxidized copper. Brass is a copper-zinc alloy that may also contain tin, aluminum, or lead. Bronze is primarily a copper-tin alloy but may also contain aluminum, nickel, phosphorus, or other elements. Copper and its alloys have many applications due to their electrical and thermal conductivity, corrosion resistance, strength and other properties.
The document describes an experiment studying the effect of metal coupling on corrosion rates in acidic and basic solutions. It finds that brass has the highest corrosion rate while aluminum has the lowest, and that corrosion rates generally decrease when metals are coupled compared to individually. The purpose is to better understand corrosion of common metals and alloys in order to reduce costs from replacement of corroded materials.
Copper manufacturing process
Content
What is copper
History of copper
General property of copper
Physical properties of copper
Manufacturing process of copper
Application of copper
This above all content are available in this presentation
This document outlines the chemical and physical properties of tin, its alloys, and applications. It discusses how tin forms alloys with many metals like copper to create bronze, an important material in early civilization. It also summarizes tin-based solder alloys that are important in electronics, replacing lead-based solders. The document concludes that tin is a key element in bronze and that most tin today is used to produce solders for electronics applications.
This document describes an experiment to determine the optimal zinc sample for plating copper to create brass alloy. The experiment tested zinc acetate, zinc sulfate, zinc dust, zinc strips, and a no zinc control. Copper strips were placed in heated mixtures of each zinc sample and then heated again to form brass. Zinc dust produced the highest brass yield, followed by zinc acetate, zinc sulfate, zinc strips, and no zinc control. Quantitative results showed zinc dust had the greatest average change in mass, indicating it plates the most zinc onto copper and produces the most brass. Therefore, zinc dust is the most effective zinc sample for industrial brass production.
This document discusses the physical properties and reactions of metals and non-metals. Metals are solid, malleable, and good conductors of heat and electricity, while non-metals can be solid, liquid, or gas and are not malleable. Metals react differently with oxygen, water, and metal salt solutions depending on their reactivity. Most metals are found naturally as ores and must be extracted from impurities. Corrosion of metals can be prevented through various coatings and by forming alloys.
Metals react with oxygen, water, and acids to form metal oxides, hydroxides, or salts. They lose electrons and become positively charged ions. Non-metals react with oxygen to form non-metal oxides, generally do not react with water or acids, and gain electrons to become negatively charged ions. Corrosion occurs as metals react with substances like oxygen and water, forming coatings like rust. Corrosion can be prevented by applying protective coatings like oil, paint, zinc plating, or by alloying metals.
Metals react with oxygen, water, and acids to form metal oxides, hydroxides, or salts. They lose electrons and become positively charged ions. Non-metals react with oxygen to form non-metal oxides, gaining electrons and becoming negatively charged ions. Corrosion occurs as metals react with substances like oxygen and water in the air, forming coatings or rust. Corrosion can be prevented by applying protective coatings like oil, paint, zinc plating, or by alloying metals.
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The document discusses the extraction of metals from their ores. It begins by describing where metals are found in nature based on their reactivity. Very reactive metals like calcium are found in the sea, while less reactive metals like aluminum and zinc are found as oxides and sulfides. The least reactive metals like gold and silver are found as free elements.
It then provides examples of metal ores found in Tanzania like copper, tin, iron, gold and uranium. The extraction process involves purifying the ore through processes like dressing, calcination and roasting. Metals are then extracted through electrolysis or chemical reduction. Common extraction methods for sodium, aluminum and iron are described. Finally, the document outlines some physical and chemical
CBSE Class 8 Science _Metals and non metalschandkec
- The document discusses substances found in nature which can be categorized as natural or artificial/man-made substances. Natural substances such as coal and petroleum are further divided into metals and non-metals. Artificial substances are those made by humans like chairs and tables.
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The document discusses non-ferrous alloys, beginning with an introduction on the limitations of ferrous alloys and advantages of using non-ferrous alloys. It then covers various non-ferrous metals and their alloys including copper and copper alloys like brass and bronze, aluminum and aluminum alloys, magnesium and magnesium alloys, and titanium and its alloys. For each metal/alloy, it describes common compositions, properties, and applications. It also discusses bearing materials and includes detailed information on composition and uses of various copper, aluminum, and magnesium alloys.
Chapter 4 materials metals and non metals.pptxAbhisesSingh
This document discusses the properties and classification of elements as metals and non-metals. It provides examples of common metals like iron, copper, and aluminum and non-metals like carbon and oxygen. It describes the physical properties of malleability, ductility, conductivity, luster, strength, and sonority that distinguish metals from brittle non-metals. It also discusses the chemical properties of metals like oxidation and reactions with water and acids, as well as uses of metals and non-metals.
The document discusses metals, minerals, ores, and metallurgy. It describes how metals are found naturally, either in their free elemental state or combined as minerals and ores. Metallurgy is the process of extracting metals from ores and purifying them. Metals are categorized based on their reactivity, and extracted using different methods like electrolysis or heating with carbon or in air. The document also discusses alloying, corrosion, and methods to prevent corrosion like coating and alloying with other metals.
This document discusses properties and uses of metals and non-metals. It begins by stating that most metals are found combined as oxides, sulfides, etc, while some non-metals exist freely. Metallurgy involves extracting metals from ores through concentration, reduction, and refining processes. Metals are malleable, ductile conductors while non-metals vary in state, are brittle, and conduct poorly. The document then covers chemical reactions of metals and non-metals and an activity series, before discussing uses of common metals and non-metals as well as alloys and corrosion prevention.
Copper and its alloys have many applications due to their high electrical and thermal conductivity, corrosion resistance, and machinability. Common copper alloys include brass, which is copper mixed with zinc, and bronze, which is copper mixed with tin. Copper is extracted from mineral ores through mining, grinding, concentration, smelting, and refining. The document outlines the key steps in extracting and processing copper from its mineral ores into its pure and alloyed forms.
When I was asked to give a companion lecture in support of ‘The Philosophy of Science’ (https://shorturl.at/4pUXz) I decided not to walk through the detail of the many methodologies in order of use. Instead, I chose to employ a long standing, and ongoing, scientific development as an exemplar. And so, I chose the ever evolving story of Thermodynamics as a scientific investigation at its best.
Conducted over a period of >200 years, Thermodynamics R&D, and application, benefitted from the highest levels of professionalism, collaboration, and technical thoroughness. New layers of application, methodology, and practice were made possible by the progressive advance of technology. In turn, this has seen measurement and modelling accuracy continually improved at a micro and macro level.
Perhaps most importantly, Thermodynamics rapidly became a primary tool in the advance of applied science/engineering/technology, spanning micro-tech, to aerospace and cosmology. I can think of no better a story to illustrate the breadth of scientific methodologies and applications at their best.
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.
Current Ms word generated power point presentation covers major details about the micronuclei test. It's significance and assays to conduct it. It is used to detect the micronuclei formation inside the cells of nearly every multicellular organism. It's formation takes place during chromosomal sepration at metaphase.
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
ANAMOLOUS SECONDARY GROWTH IN DICOT ROOTS.pptxRASHMI M G
Abnormal or anomalous secondary growth in plants. It defines secondary growth as an increase in plant girth due to vascular cambium or cork cambium. Anomalous secondary growth does not follow the normal pattern of a single vascular cambium producing xylem internally and phloem externally.
Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...Travis Hills MN
Travis Hills of Minnesota developed a method to convert waste into high-value dry fertilizer, significantly enriching soil quality. By providing farmers with a valuable resource derived from waste, Travis Hills helps enhance farm profitability while promoting environmental stewardship. Travis Hills' sustainable practices lead to cost savings and increased revenue for farmers by improving resource efficiency and reducing waste.
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...Sérgio Sacani
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
The debris of the ‘last major merger’ is dynamically youngSérgio Sacani
The Milky Way’s (MW) inner stellar halo contains an [Fe/H]-rich component with highly eccentric orbits, often referred to as the
‘last major merger.’ Hypotheses for the origin of this component include Gaia-Sausage/Enceladus (GSE), where the progenitor
collided with the MW proto-disc 8–11 Gyr ago, and the Virgo Radial Merger (VRM), where the progenitor collided with the
MW disc within the last 3 Gyr. These two scenarios make different predictions about observable structure in local phase space,
because the morphology of debris depends on how long it has had to phase mix. The recently identified phase-space folds in Gaia
DR3 have positive caustic velocities, making them fundamentally different than the phase-mixed chevrons found in simulations
at late times. Roughly 20 per cent of the stars in the prograde local stellar halo are associated with the observed caustics. Based
on a simple phase-mixing model, the observed number of caustics are consistent with a merger that occurred 1–2 Gyr ago.
We also compare the observed phase-space distribution to FIRE-2 Latte simulations of GSE-like mergers, using a quantitative
measurement of phase mixing (2D causticality). The observed local phase-space distribution best matches the simulated data
1–2 Gyr after collision, and certainly not later than 3 Gyr. This is further evidence that the progenitor of the ‘last major merger’
did not collide with the MW proto-disc at early times, as is thought for the GSE, but instead collided with the MW disc within
the last few Gyr, consistent with the body of work surrounding the VRM.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
3. I wish to express my deep gratitude and
sincere thanks to the Principal MR AVDESH
DUBEY, Kendriya Vidyalaya Sec 2 RK Puram
New Delhi for his encouragement and for all
the facilities that he provided for this project
work. I sincerely appreciate this magnanimity
by taking me into her fold for which I shall
remain indebted to her. I extend my hearty
thanks to Mr. AK SHARMA, Chemistry teacher
,who guided me to the successful completion
of this project. I take this opportunity to express
my deep sense of gratitude for him invaluable
guidance, constant encouragement , immense
motivation , which has sustained my efforts at
all the stages of this project work…I can’t
forgot to offer my sincere thanks to parents
and also to my classmates who helped me to
carry out this project work successful and for
their valuable advice and support , which I
received from them time to time….
4. certificate
Department of Chemistry
Kendriya vidyalaya
Sec 2 RK Puram New Delhi
This is to certify that AMIT KUMAR of class XII B has prepared the Investigatory
chemistry project entitled “ study of constituents of Alloys ”. Under the guidance of
Mr AK SHARMA .
The project is the result of his efforts and endeavours. This project is genuine and
does not indulge in plagiarism of any kind. The refrences taken in making this
project have been declared at the end of this project.
signature of external examiner signature of teacher
5. 1-- Introduction
2-- Some Common Alloys
3-- Preparation of alloys
4-- Analysis of an alloy
5-- Experiment 1
to analyze a sample of brass
qualitative
6-- Experiment 2
to analyze a sample of bronze
qualitatively
7-- Uses of Alloy
8-- Bibliography……
6. An Alloy is a homogenous mixture of two or more metals or a non-metal.
An alloy of mercury with another metal is called amalgam.
Alloys are usually harder than their components but very often less ductile and
less malleable. Thus the hardness of gold is increased by addition of copper to it.
The melting point of an alloy is always lower than the melting points of the
constituent metals. Other properties such as reactivity towards atmospheric
oxygen and moisture, mechanical strength, ductility, colour etc. also under goes
a change when an alloy is made from its constituents (metals). This change of
properties is very useful and makes an alloy beneficial.
Some of the alloys along with their composition is given below.
1. Brass :-
It consists copper-50-90%.
Zinc. : 20-40%
and small amounts of tin, lead and iron.
2. Bronze : It consists copper 60-90%.
3. Tin : 5-35%
and also contains small amounts of lead, iron and zinc.
Duralumin : It consists Al : 95%, Cu = 4%
Mn = 0.5%, Mg = 0.5%
4. Gun Metal : It consists copper 85 - 90%
5. Zinc. : 1-3%
6. Tin : 8-12%
The composition of alloys may differ slightly depending upon the quality of
the alloy though the main components remain the same.
7. Amalgam
Any alloy of mercury is called an amalgam. Most metals are
soluble in mercury, but some (such as iron)are not. Amalgams are
commonly used in dental fillings because they have been relatively
cheap, easy to use, and durable. In addition, until recently, they
have been regarded as safe. They are made by mixing mercury
with silver ,copper ,tin , and other metals. The mercury content of
dental fillings has recently stirred controversy, based on the
potentially harmful effects of mercury.
Mercury amalgams have also been used in the process of mining
gold and silver, because of the ease with which mercury
amalgamates with them. In addition , thallium amalgam is used as the liquid
material in thermometers, because it freezes at -58°C,whereas pure mercury
freezes at -38°C.
Brass
A decorative brass paperweight (left), along with zinc and copper
samples.
Brass is the term used for alloys of copper and zinc in a solid
solution. It has a yellow color, somewhat similar to gold. It was
produced in prehistoric times, long before zinc was discovered, by
melting copper with calamine, a zinc ore.
The amount of zinc in brass varies from 5 to 45 percent, creating
a range of brasses, each with unique properties. By comparison,
bronze is principally an alloy of copper and tin.
8. Despite this distinction, some types of brasses are called bronzes.
Brass is relatively resistant to tarnishing and is often used for
decorative purposes. Its malleability and acoustic properties have
made it the metal of choice for musical instruments such as the
trombone, tuba, trumpet, and euphonium. Although saxophones
And harmonicas are made out of brass, the saxophone is a
woodwind instrument, and the harmonica, a free reed aero phone.
In organ pipes designed as "reed" pipes, brass strips are used as
the "reed."
Aluminum makes brass stronger and more corrosion-resistant. It
forms a transparent, self-healing, protective layer of aluminum
oxide (A𝑙2O3) on the surface. Tin has a similar effect and finds its
use especially in seawater applications (naval brasses).
Combinations of iron, aluminum, silicon, and manganese make brass
resistant to wear and tear.
Bronze
Bronze refers to a broad range of copper alloys, usually with tin
as the main additive, but sometimes with other element s such as
phosphorus,manganese,aluminum, or silicon. Typically, bronze is
about 60 percent copper and 40 percent tin. The use of bronze
was particularly significant for early civilizations, leading to the name "Bronze
Age." Tools, weapons,
armor, and building materials such as decorative tiles were made
of bronze, as they were found to be harder and more durable
than their stone and copper predecessors.
9. In early use, the natural impurity arsenic sometimes created a superior
natural
alloy, called "arsenical bronze."
Though not as strong as steel, bronze is superior to iron in nearly
every application. Bronze develops a patina (a green coating on
the exposed surface), but it does not oxidize beyond the surface.
It is considerably less brittle than iron and has a lower casting
temperature. Several bronze alloys resist corrosion (especially by
seawater) and metal fatigue better than steel; they also conduct
Heat and electricity better than most steels.
Bronze has myriad uses in industry. It is widely used today for
springs, bearings, bushings, and similar fittings, and is particularly
common in the bearings of small electric motors. It is also widely
used for cast metal sculpture and is the most popular metal for
top-quality bells and cymbals.
Commercial bronze, otherwise known as brass, is 90 percent
copper and 10 percent zinc. It contains no tin
10. Preparation of Alloys
Alloys are prepared from the techniques of fusion, compression or
simultaneous electro - deposition. Generally the components are mixed
together in proper properties in a fuse clay crucible, melted and stirred with a
piece of charcoal to avoid oxidation. The molten mixture is now allowed to
cool. When an alloy is obtained e.g. brass is prepared by above melted.
Analysis of an alloy
The complete analysis of an alloy involves two steps.
1. Qualitative Analysis :
This involves identification of the components of the alloys.
2. Quantitative Analysis :
This involves determination of the components of the alloy. It involves the
separation of the components from the alloy quantitatively followed by
determination of percentage of each component volumetrically or
gravimetrically.
In this project we will carry out qualitative analysis only.
Objectives of Project :
In this project, our aim is to know the various metals present in the given
sample of alloy.
11.
12. Requirements : China dish, test-tube funnel, filter paper and common laboratory
reagents.
Theory :
Brass is an alloy of copper and zinc. with the following.
Composition :
Cu = 60-90% and Zn. = 10-40%.
Thus Cu and Zn. form the main constituents of brass. Both these metals dissolved in 50%
of nitric acid due to formation of nitrates which are soluble.
3Cu + 8HNO3(Dil) → 3Cu(NO3)2
+ 2NO + 4H2O
or
Cu + 8H+
+ 2NO3
−
→ 3C 𝑢2+
+ 2NO + 4H2O
4Zn + 10HNO3(Dil) → 4Zn(NO2) 2
+ N2O + 5H2O
4Zn + 2NO3
−
+ 10H+
→ 4Z 𝑛2+
+ N2O + 5H2O
The solution is boiled to expel the oxides of nitrogen and the resulting solution is tested for
Cu 2+
and Z 𝑛2+
ions.
Procedure :
1. Place a small piece of brass in a china dish and heat this with minimum
quantity of 50% HN 𝑂3so as to dissolve the piece completely.
2. Continue heating the solution till a dry solid residue is obtained.
3. Dissolve the solid residue in dil. HCl and filter. Add distilled water to the
filtrate.
4. Pass H2S gas through the filtrate. A black precipitate of copper sulphide is
obtained. Separate the black ppt. and keep the filtrate for the test of Zn2+
ions Dissolve black ppt. by heating them with 50% HNO3. To this solution add
ammonium hydroxide solution. Appearance of deep blue coloration in the
solution shows the presence of copper ions in the solution.
5. To test Zn2+
ions, boil the filtrate to remove H2S gas, then add solid
NH4Cl to this and heat to dissolve NH4Cl. Add excess of NH4OH so that a
solution is ammoniacal. Now pass H2S gas through this ammoniacal solution.
Dirty white or grey precipitation indicate zinc. Separate the precipitates and
dissolve it in minimum amount of dil. HCl. Boil to expel H2S gas and add
potassium Ferro cyanide solution, white or bluish white ppt. confirm
Zn2+
ions in the solution.
Result :
The given sample of brass contains copper and zinc. metals as the
main constituents.
13.
14. Requirements : China dish, test-tube funnel, filter paper and common
laboratory reagents.
Theory :
Bronze is an alloy of copper and tin with the following.
Composition :
Cu = 88-96% and Sn. = 4-12%.
Thus copper and zinc. form the main constituents of bronze. Both these
metals dissolved in nitric acid.
3Cu + 8H+
+ 2NO3
−
→ 3Cu2+
+ 2NO + 4H2O
4Sn + NO3
−
+ 10H+
→ 4Sn2+
+ NH4 + 3H2O
(Cold and Dil. Acid)
Sn + 4NO3
−
+ 4H+
→ H2SnO3 + 4NO2 + H2O
(Conc. acid) (Metastannic Acid)
Excess of nitric acid is removed by heating the solution. The resulting solution
now would contain Cu2+
ions and metastannic acid. This solution is acidified
with dil. HCl and H2S gas is passed when the sulphides of copper and tin are
formed.
Cu2+
+ S2- CuS (Black ppt.)
H2SnO3 + 2H2S SnS2 (Black ppt.) + 3H2O
The sulphides are separated by boiling the ppt. with yellow ammonium
sulphide when SnS2goes into solution as thiostannate where as CuS is not
affected.
SnS2 + (NH4) 2S(NH4) 2SnS2 (Soluble)
Ammonium thiostannate.
CuS + + (NH4) 2S CuS (Unaffected)
Black ppt.
The soluble black ppt. is tested for Cu2+
ions and the solution is tested for
Sn2+
ions as in elementary qualitative analysis.
15. Procedure :
1. Take about 1g. of small pieces of bronze in a china dish and add to it 5-10
ml. of dil. HNO3.
2. Heat the contents slowly to dissolve copper and tin completely and then
boil the contents to a paste to remove excess of HNO3. All this is carried out
in cup board.
3. Dissolve this dry mass in distilled water containing HCl (1:1) to get a clear
solution.
4. Transfer the solution in a test tube and pass H2S in excess i.e. till the
precipitation is complete. Filter and reject the filtrate.
5. Take the black ppt. in a test tube and add to it 2-3 ml. of yellow ammonium
sulphide and heat. Filter the contents. Black residue is tested for Cu2+
ions
and filtrate is tested for Sn2+
ions.
6. Analysis of black residue :
Transfer a little of the black ppt. into a test tube. Add to it 2-3 ml. of 50%.
HNO3 and boil the contents of the tube. A light blue or green sol. indicates the
presence of Cu2+
. Divide this sol. into two parts.
(a) To one part add excess of NH4OH a deep blue coloration confirms the
presence of Cu2+
ions.
(b) Acidify the second part with acetic acid and add K4[Fe (CN)6] i.e.
potassium ferrocyanide solution. A reddish brown ppt. confirms the presence
of Cu2+
ions.
7. Analysis of filtrate :
Boil the filtrate with 1 ml. of dil. HCl. A yellow ppt. is obtained. Dissolve in 1
ml. conc. HCl. To this solution add 0.5 g. of zinc. dust and boil it for 2-3
minutes. Filter and to filtrate add 1-2 ml. of mercuric chloride solution. A white
ppt. turning grey on standing confirms the presence of Sn4+
ions.
Result :
The given sample of bronze contains - Cu and Sn as the main constituents.
16. i) To modify chemical reactivity :-
When sodium is used as reducing agent it is too reactive to be used but its
allay with mercury, called sodium amalgam can be safely used as reducing
agent.
ii) To increase hardness :-
Hardness of gold is increased by adding copper to it. Also zinc is added to
copper to make copper hard in form of brass.
iii) To increase tensile strength :-
Nickeloy, an alloy of Nickel (1%), Copper (4%) and aluminium (95%) has high
tensile strength.
iv) To lower the melting point :-
Solder metal which is an alloy of Sn(30%) and Pb(70%) has very less meting
point as compared to melting points of Sn and Pb.
v) To modify the colour :-
Aluminium bronze an alloy of Cu and Al has beautiful golden colour.
vi) To resist corrosion:-
Iron gets rusted and corroded. Its corrosion takes place with time but
stainless steel, an alloy of iron and carbon get not rusted the composition of
stainless steel is :
Iron - 98%
Carbon - 2%
17. 1. XII class Chemistry NCERT Books
2.XII class Chemistry Practical Book
3.Photos from Google images.
4.More Information from Wikipedia..
THE END !