Applied Chemistry 2 Marks Questions (with Answers) PDF

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This document contains 2 marks questions and answers related to applied chemistry. It covers topics including chemical bonding, catalysts, and metallic properties. This is suitable for undergraduate chemistry students.

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PARUL INSTITUTE OF ENGINEERING & TECHNOLOGY(DS-1ST SHIFT) SUBJECT: APPLIED CHEMISTRY ASSIGNMENT Short Question – Answers CHAPTER -1 CHEMICAL BONDING AND CATALYSIS 1. Define Ionic bonding and covalent bonding. Ans: Ionic Bond - The bond formed by transfer of electrons due to which cation and ani...

PARUL INSTITUTE OF ENGINEERING & TECHNOLOGY(DS-1ST SHIFT) SUBJECT: APPLIED CHEMISTRY ASSIGNMENT Short Question – Answers CHAPTER -1 CHEMICAL BONDING AND CATALYSIS 1. Define Ionic bonding and covalent bonding. Ans: Ionic Bond - The bond formed by transfer of electrons due to which cation and anion are formed is called Ionic Bonding. Covalent Bonding: The bond formed by sharing of electrons is called Covalent bonding. 2. Define Coordinate covalent bonding. Ans: The bond in which both the electrons are shared by only one atom (lone pair of electrons are shared) is called Coordinate covalent bonding. 3. Define Orbit and Orbital. Ans: Orbit : The circular path around the nucleus in which the electrons are continuously rotating is called Orbit. It is the main energy shell where the electrons are present. Orbital: The probable space around the nucleus where the probability of finding the electrons are maximum is called as Orbital. 4. State the four Quantum number. Ans: The Four Quantum number are as follows: 1. Principal Quantum Number 2. Angular or orbital Quantum Number 3. Magnetic Quantum number 4. Spin Quantum number 5. Define Metallic bonding. Ans: The bond formed as a result of simultaneous attraction of an electron by two o r more than two positive ions of the metal is called as metallic bond and they are electrostatic in nature. 6. Define Hydrogen bonding. Ans: The force of attraction between one covalently bonded hydrogen atom of one molecule and one electronegative atom of another molecule is called as Hydrogen Bonding which is denoted by Dotted line. 7. State the Different properties of Metals. Ans: Metals exhibit certain characteristic properties which are as follows: (i) High thermal and electrical conductivity. (ii) High melting and boiling points. (iii) High density and mechanical strength. (iv) High ductility and malleability. (v) Metallic lustre. 8. What is polar and non-polar covalent bonding? 1. Ans: When two atoms of the same element involves in a covalent bond to form a molecule, the shared pair of electrons will be at the exact midway between the two atoms non polar covalent bond is formed. 2. A covalent bond formed between two different atoms is known as Polar covalent bond. 9. Draw the structure of FCC, BCC and HCP. Ans: FCC BCC HCP 10. Define: Catalytic Promoter, Catalytic Inhibitor and Catalytic Poisons. Ans: Catalytic Promotor: Substances which themselves are not catalysts, but when mixed in small quantities with the catalysts increase their efficiency are called as promoters or activators. For example - (i) In Haber’s process for the synthesis of ammonia, traces of molybdenum increases the activity of finely divided iron which acts as a catalyst. Catalytic Inhibitor: The Foreign substance which are not catalyst but they hinders the catalyst activity are called as catalytic inhibitor. Catalytic poisons : Substances which destroy the activity of the catalyst by their presence are known as catalytic poisons. For Example - The presence of traces of arsenious oxide in the reacting gases reduces the activity of platinized asbestos which is used as catalyst in contact process for the manufacture of sulphuric acid. 11. Name the element which are having FCC, BCC and HCP structure. Ans: The Substance having FCC structure are -ALUMINIUM (Al), COPPER (Cu), GOLD (Au). The substances having BCC structure are - IRON (Fe), TUNGSTON (W), CHROMINIUM (Cr). The substances having HCP structure are - CADMIUM (Cd), MAGNESIUM (Mg), ZINC (Zn). 12. Draw the shapes of s, p ,d Orbitals Ans: 13. Define Catalysis, Positive catalyst, negative catalyst Autocatalyst.  Ans: Positive catalyst : When the rate of the reaction is accelerated by the addition of the catalyst, it is said to be a positive catalyst.  Negative catalyst : There are certain, substance which, when added to the reaction mixture, retard the reaction rate instead of increasing it. These are called negative catalyst or inhibitors.  Auto-catalysis In certain reactions, one of the product acts as a catalyst. In the initial stages the reaction is slow but as soon as the products come into existences the reaction rate increases. This type of phenomenon is known as auto-catalysis. 14. Why metals are malleable and ductile. Ans: Metals are malleable and ductile. The delocalized electrons in the 'sea' of electrons in the metallic bond, enable the metal atoms to roll over each other when a stress is applied. 15. Define Catalyst and Catalysis. Ans: “A substance which changes the reaction rate without affecting the overall energetic of the reaction is termed as a catalyst and the phenomenon is known as catalysis.” 16. State the Characteristic of Ionic compound 1. Ans: They are generally hard crystalline in nature. 2. Ionic bonds are unidirectional and rigid. 3. They have high melting point and high boiling point because of the strong electrostatic force of attraction. 4. They are generally non-conductor of electricity but in aqueous medium they are good conductors of electricity. 5. They are soluble in water but insoluble in organic solvent. 17. State the characteristic of Covalent compound. Ans: 1. They have low melting and boiling points. 2. The covalent compounds are generally amorphous in nature. 3. They exist mostly as solid, gases or liquids. 3. They are poor conductors 4. They are insoluble in water but soluble in organic solvent. 5. The covalent bond is directional and as such there is a possibility of position isomerism and stereo isomerism amongst these compounds. 18. State the different types of hydrogen bonding. Ans: Intermolecular Hydrogen Bonding ---Hydrogen bond between the molecules Intramolecular Hydrogen bonding ---Hydrogen bond within the same one molecule 19. State the different application of catalyst. Ans: Process Catalyst Making ammonia Iron Making synthesis gas (carbon monoxide and Nickel hydrogen) Catalytic cracking of gas oil Zeolite Platinum and rhenium on Reforming of naphtha alumina Making epoxyethane Silver on alumina Making sulfuric acid Vanadium(V) oxide on silica Making nitric acid Platinum and rhodium UNIT II CONCEPT OF ELECTROCHEMISTRY 1. Define Degree of Ionization. Ans: The fraction of the total number of molecules ionized in the electrolytic solution is known as Degree of Ionization. ions = 2. What is Reference Eletrode?  Ans: The Electrode which have standard Potential value and with which we can compare the potential of an other electrodes is called a Reference Electrode. 3. Name the Factors affecting degree of Ionization. Ans: The factors affecting degree of Ionization are – Nature of Electrolyte, Temperature, Dilution of solvent and Nature of Solvent. 4. What is Electrochemical Cell? Ans: The device which changes the chemical energy into electrical energy is called Electrochemical Cell. 5. What is Buffer solution? Give Example Ans: The solution which the resist the change in pH of the solution is called buffer solution. For Example the solution of Acetic Acid and salt of Acetic acid behave as Acidic Buffer. 6. What is pH? Draw the pH scale. Ans: The negative logarithm of 3 + ion to the base 10 is called pH of the solution. It is the measure of acidity and alkalinity of a solution. The pH value ranges from 0 to 14. 7. What is Electrode and give example. Ans: An Electrode is a conductor which passes or allow to flow the electrons from one end to other end. The Electrode can be defined as “A metal strip or rod dipped in an electrolytic solution of its own ions and on whose surface the oxidation and reduction reaction takes place is called electrode. They are mainly of three types: a. Active Metal Electrode: Zn, Cu, etc. b. Inert Electrode of metal or non metal: Pt, Graphite, etc. c. Gaseous Electrode: H2, Cl2, etc. 8. What is Half Cell? Ans: The Electrode and the solution in which it is dipped is collectively known as Half cell. The Half cell is constructed by dipping the metal or non metal strip into an electrolytic solution of its own ion. The representation of the half cell is shown by inserting single vertical line between an electrode and active ions. 9. What is Electrolysis? Ans: The Chemical Change caused by the passage of an electric current through a solution of an electrolyte is called Electrolysis. OR The process in which an electric current is passed through the solution of an electrolyte and due to the passage of electric the cations and anions moves towards their respective electrodes is called Electrolysis. 9. What is Eletrorefining? Ans: The metals are purified by electrolysis method which is called electrorefining. 10. What is Electroplating? Ans: The process of coating an inferior metal with a superior metal by electrolysis is known as electroplating. 11. State the Faradays law of Electrolysis. Ans: Faraday’s First Law of Electrolysis : In electrolysis, when an electric current is passed through an electrolyte, then the amount of the mass of an element deposited on the cathode, is directly proportional to the amount of current passed, Q, through the electrolytic solution; and the equivalent weight (atomic weight) of the metal. W∝ W ∝ × W = E× × where I = the current in amperes (A), t = time in second E = a constant of proportionality called electrochemical equivalent of the substance. Faraday’s Second Law of Electrolysis : When the same quantity of charge is passed through the different series of electrolytic cell containing different electrolytes, then the amount of products obtained at the different electrodes are directly proportional to their equivalent weights. Hence according to first law = × Then Q= 96500 Coulomb, W becomes gram equivalent mass that is E ∴ = × 96500 = 96500 1 1 ∴ = 2 2 12. State the Nernst Equation for single electrode. Ans: The equation showing relation be the potential of the non standard electrochemical cell and the concentration of the solution is known as Nernst Equation. 13. Give the standard condition of a cell. Ans: Temperature – 25oC , Concentration – 1M and Pressure – 1 atm 14. Draw the diagram of an Electrochemical Cell. Ans: 15. Calculate the pH of 0.002 M HCl solution. 16. Calculate the pH of 0.001 H2SO4 Solution. 17. Calculate the pH of0.05 M NaOH solution. UNIT III CORROSION AND ITS PREVEMTION 1. What is Corrosion? Give example. Any Process of deterioration (or destruction) and consequent loss of a solid metallic material, through an unwanted chemical or electrochemical attack by its environment starting at its surface is called corrosion. 2. What are the different factors affecting corrosion? Ans: The factors affecting corrosion rate are – Nature of Oxide film formed on the surface of the metal, Temperature, pH, Moisture content and Area of Cathode. 3. What is metal cladding? Ans: A process which involves binding of dense and homogeneous layer of coating material to the base metal on one or both the sides. 4. What is metal spraying? Ans: The metal spray process is basically the spraying of molten metal onto a surface to provide a coating. Material in wire form is melted in a flame (oxy-acetylene flame most common) and atomized using compressed air to form a fine spray. 5. Why do metals corrode? Ans: Most metals (Except Gold, Platinum) exist in nature in combined forms as their oxides, Chlorides, Sulphides, carbonates, etc. The combined form of the metal are called as minerals or ores which are reduced to their metallic states during extraction process. 6. State the different types of oxide layer formed due to corrosion? Ans: Stable film: Adheres tightly to the metal surface and impervious in nature and prevents further corrosion. Unstable film: Decomposes back into metal and oxygen. So, oxidation corrosion is not possible. Volatile film: Film gets volatilizes, thereby leaving the underlying metal surface exposed for further corrosion. Porous Film: Sometimes the oxide film have pores or cracks. Hence diffusion of oxygen takes place through these pores leading to further corrosion 7. What is Crevice corrosion? Ans: This type of corrosion is produced at the region of contact of metals with the metals or non- metals in presence of impurities lying between the contact area. 8. What is pitting corrosion? Ans: It is a localized corrosion resulting in formation of pits or cavities in the metals. 9. What is waterline corrosion? Ans: Corrosion takes place along a line just beneath the level of the water meniscus. The area above the waterline (highly oxygenated) act as cathode and surface below act as anode (less oxygenated). Hence corroded. 10. Why L, T and U shape are avoided for designing the shape of article? Ans: The Number of angles, corners, edges in any design should be avoided so that we can Minimize the accumulation of dirt, dust particles, etc. in the corners or joints formed due to L T and U Shaped. 11. What is Galvanizing? Ans: The process of coating of Zinc on the base metal to protect it from corrosion is called Galvanizing. 12. What is Tinning? Ans: The process of coating of Tin on the base metal to protect it from corrosion is called Tinning. 13. State the different types of coating method of Articles. Ans: The Different types of Coating method are – 1. Galvanizing 2. Tinning 3. Metal Spraying 4. Metal Cladding 5. Sheradizing 6. Electroplating 7. Use of Inhibitor on the surface of Metal UNIT IV WATER TREATMENT 1. State the different types of impurities present in water. Ans: The different Types of Impurities present in water- 1. Susspended impurities, 2. Colloidal Impurities 3. Dissolved Impurities and 4. Microorganism and Pathogenic Bacteria. 2. State the different sources of water. Ans: Rain water, Ground Water and Surface water. 3. Define Hard water and soft water. Ans: Hard Water - The water which does not produce good lather and contains impurities is called Hard water. Soft. Water: The water Which produces good lather and does not contain any impurities is called soft water. 4. State the difference between Temporary and Permanent Hardness. Sr. Temporary Hardness Permanent hardness No. 1 It can be removed by simple boiling the It cannot be removed by boiling the water water but require chemical treatment. 2 It is due to the presence of carbonate It is due to the presence of Sulphate and bicarbonate salts of calcium and and chloride salt of calcium and magnesium magnesium. 5. Name the different salts producing hardness in water. Ans: Calcium Bicarbonate, Magnesium Carbonate and Magnesium Bicarbonate, Calcium chloride and Magnesium chloride, Calcium sulphate and Magnesium sulphate, Calcium silicate, etc. 6. Convert 243 ppm into degree French and degree clark. 7. Convert 2.5 oCl to ppm and degree French. 8. Name some coagulant used to remove colloidal impurities from water. Ans: Alum, Copperas(Ferrous Sulphate) and Copper Aluminate 9. Give the full form of EDTA and EBT. Ans: EDTA – Ethylene diamine Tetra Acetic acid and EBT – Eriochrome Black T 10. Name the different analysis of water sample. Ans: The different analysis carried out for water sample are – COD, BOD, Water Hardness, Total dissolved solids, alkalinity of water, Dissolved Oxygen and carbon dioxide test and Free chlorine test. 11. What is Softening of water? Ans: The Process of removing of dissolved imprities from hard water and making it soft through chemical treatment is called softening of water. 12. What is Screening in treatment of water? Ans: Screening : The process of removing the floating impurities from water by passing it from different screen is called screening. 13. What is Sedimentation? Ans: Sedimentation: The process of removing the suspended impurities from water by allowing the water to be kept undisturbed for several hours in a tank is called sedimentation. 14. What is Coagulation? Ans: Coagulation is the Process of removing the colloidal impurities by addition of requisite amount of chemical which is called as coagulants, to water before sedimentation. 15. What is Sterilization of water? Ans: The Process of removing the disease-causing bacteria and microorganism from water and making the water safe for its use is called sterilization of water. 16. What is Scale and Sludge? Ans: Scales are hard, adhering precipitates formed on the inner walls of the boilers. Scales are stick very firmly on to the inner walls of the boiler. It is removed with chisel and hammer. Scales are formed by decomposition of calcium bicarbonate in low pressure boilers. Sludge is a soft, loosy and slimy precipitate formed within the boiler. It is formed at comparatively colder portions of the boiler and collects in the area where flow rate is slow. Ex: MgCO3, MgCl2, CaCl2, MgSO4. 17. What is Priming and Foaming? Ans: Priming : When a boiler produces steam rapidly, some particles of the liquid water are carried along with the steam. This process of "Water-steam" formation is called priming. Foaming is the production foam or bubbles in boilers, which do not break easily. Foaming is due to presence of substances like oil. 18. What is Caustic Embrittlement? Caustic embrittlement is a phenomenon that occurs in boilers where caustic substances accumulate in boiler materials. This occurs at temperatures of 200°-250°C as a result of local deposition of concentrated hydroxide. 19. What is Boiler Corrosion? Ans: The Decay of Boiler material due to the chemical or electrochemical attack of the environment of boiler is called as boiler corrosion. 20. What are the causes of Boiler corrosion? Ans: The Causes of Boiler Corrosion are  Presence of Dissolved Oxygen in boiler water.  Presence of Dissolved Carbon Dioxide in boiler water  Unbalanced pH of boiler water.  No periodic maintenance. UNIT V LUBRICANT AND LUBRICATION 1. What is Lubricant? Ans: Lubricant is a material that reduces the friction arising due to sliding/gliding/rolling/moving of two different surfaces in contact with each other. 2. What is Lubrication? Ans: Lubrication is the process or technique to reduce wear of one or both surfaces in close proximity and moving relative to each other, by interposing a substance called as lubricant between the surfaces to carry or to help carry the load between the opposing forces. 3. What is Meant by Flash point and Fire point? Ans: Flash point: The lowest temperature at which the oil begins to give enough vapors which give momentary flash of light when a flame is applied to it. Fire Point: The minimum temperature at which the oil gives enough which vapors which catch fire and burns continuously at least for 5 seconds when flame is applied to it. 4. What is Viscosity Index? Ans: “The rate of change of viscosity of a liquid (oil) with change in temperature is known as Viscosity index.” 5. Define Neutralization number and emulsification Number. Ans: The number in milligrams of KOH required to neutralize free acid in one gram of oil is called Neutralization number. Emulsification is the property of oils to get intimately mixed with water, forming a mixture called emulsion. 6. What is Boundary Lubrication? Ans: Boundary lubrication is defined as that in which the sliding surfaces are separated by a very thin molecular film of lubricant, so that the chemical and physical natures of the surfaces and the lubricant are of major importance. 7. What is meant by Thick film lubrication? Ans: Thick film lubrication: It is the condition of lubrication where two surfaces of the bearings are completely separated by the film of liquid, in this type of lubrication, the load is taken completely by the oil film. 8. Give Classification of Lubricants with example. Ans: 9. Name some Synthetic liquid lubricant. Ans: Cup Grease, Soda Based Grease, Lithium soap base grease, Axle grease 10. What is Saponification Value? Ans: : It is the number of milligrams of KOH required to saponify fatty material present in 1 gm of the oil. 11. Define pour point and cloud point. Ans: Cloud point: The temperature at which oil becomes cloudy in appearance is called its cloud point. Pour Point: The temperature at which the liquid no longer flow (ceases to flow) on cooling. 12. Give names of semisolid Lubricant. Ans: Cup Grease, Soda Based Grease, Lithium soap base grease, Axle grease UNIT VI POLYMERS, ELASTOMERS AND ADHESIVES 1. What are monomers and polymer? Ans: Polymers the macromolecules of high molecular weight which is built up by linking together of a large number of small molecules called as monomers. Monomer is the Simple organic molecules which can form polymers by linking together with chemical bonding. 2. State the condition required by monomer to form polymer. Ans: The condition required to forma polymer is 1. monomer should contain double bond or triple bond 2. Monomer should have functional groups 3. Give classification of Polymers. 4. What is Elastomer? Ans: A Polymer substance in which its original length can be increased by 10 to 15%,without breaking it on applying force on it and after removal of the external force, retains its original shape and volume is called elastomers. 5. What is Vulcanization of rubber? Ans: Vulcanization or vulcanization is a chemical process for converting rubber or related polymers into more durable materials via the addition of sulfur or other equivalent "curatives" or "accelerators". These additives modify the polymer by forming crosslinks (bridges) between individual polymer chains. Vulcanized materials are less sticky and have superior mechanical properties. 6. Give full form of PE, PTFE, PVC and PS. Ans: PE- Polyethylene, PTFE – PolytetraFluoro Ethylene, PVC – Poly Vinyl Chloride and PS – PolyStyrene 7. Give example of Thermoplastic. Ans: PE- Polyethylene, PTFE – PolytetraFluoro Ethylene, PVC – Poly Vinyl Chloride and PS – PolyStyrene, PET – Poly Terphthalate, Poly Acrylonitrile 8. Give Example of Thermosetting plastics. Ans: Bakelite, Epoxy Resin, Melamine and silicone 9. What are Adhesives? Ans; An adhesive is a material that can adhere (stick) to other materials and help attach them together. 10. Give classification of Adhesives with examples. Ans: UNIT VII FUELS AND COMBUSTION 1. What are Fuels? Ans: Any substance which upon combustion produces a usable amount of energy is known as fuel. For example wood, coal, biogas, LPG, petrol, diesel etc. 2. What is Calorific Value? Ans: Calorific value is the amount of heat energy present in food or fuel and which is determined by the complete combustion of specified quantity at constant pressure and in normal conditions. 3. Give Classification of Fuels with examples. 4. State the Dulong Formula./. State the HCV and LCV formula.

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