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51.

How Are Vessel Lined With Glass Or How Are They Coated?

Answer»

First, the glass mixture is smelted for FORM the proper recipe based on temperature and pressure requirements of the vessel. Then the glass is ground into tiny particles and suspended in a LIQUID medium CALLED a slip. This mixture is then spayed onto the surface to be coated. The vessel is then heated to 800 0C to bond the glass to the steel (USUALLY carbon steel). The vessel is then SLOWLY cooled.

First, the glass mixture is smelted for form the proper recipe based on temperature and pressure requirements of the vessel. Then the glass is ground into tiny particles and suspended in a liquid medium called a slip. This mixture is then spayed onto the surface to be coated. The vessel is then heated to 800 0C to bond the glass to the steel (usually carbon steel). The vessel is then slowly cooled.

52.

At What Temperature Is Glass Fused To Steel In The Making Of Glass-lined Equipment?

Answer»

The borosilicate glass is TYPICALLY FUSED to carbon STEEL at a temperature of about 800 0C.

The borosilicate glass is typically fused to carbon steel at a temperature of about 800 0C.

53.

What Are Some Typical Applications For Glass-lined Reactors?

Answer»

Glass-lined equipment gives superior protection to all MINERAL acids at all concentration and temperatures. ONE exception is HYDROFLUORIC acid. They are also used is high-purity processes where cleanliness is very important. Using glass-lined equipment HELP eliminate the possibility of metal contamination. A third application is in polymerization. METALLIC vessels sometimes tend to allow the polymer to stick to the walls of the vessels while glass-lined vessels have good anti-stick properties.

Glass-lined equipment gives superior protection to all mineral acids at all concentration and temperatures. One exception is hydrofluoric acid. They are also used is high-purity processes where cleanliness is very important. Using glass-lined equipment help eliminate the possibility of metal contamination. A third application is in polymerization. Metallic vessels sometimes tend to allow the polymer to stick to the walls of the vessels while glass-lined vessels have good anti-stick properties.

54.

Is There Any Way To Slow Coke Formation In Ethylene Furnaces?

Answer»

Westaim Corporation has a commercial PROCESS for applying a special coating to the tubes used in ethylene furnaces. Westaim claims that coke buildup is reduced to one-forth to one-tenth of the normal rate. The coating consists of a combination of METAL, ceramic powder, and a polymer. Once the coating is applied, the tubes are then heat-treated and REACTED with an unspecified gas. WELDS cannot be coated with this process.

Westaim Corporation has a commercial process for applying a special coating to the tubes used in ethylene furnaces. Westaim claims that coke buildup is reduced to one-forth to one-tenth of the normal rate. The coating consists of a combination of metal, ceramic powder, and a polymer. Once the coating is applied, the tubes are then heat-treated and reacted with an unspecified gas. Welds cannot be coated with this process.

55.

What Information Is Needed To Specify A Mixer?

Answer»
  1. Specific Gravity
  2. Fluid Viscosity
  3. Phase to be dispersed
  4. Solid-liquid SYSTEMS

The settling VELOCITIES of the 10, 50, and 90 percent weight fractions of the particle size distribution should be available. 5. For gas systems, the standard and ACTUAL flow RATES will be needed.

The settling velocities of the 10, 50, and 90 percent weight fractions of the particle size distribution should be available. 5. For gas systems, the standard and actual flow rates will be needed.

56.

How Can Viscosity Affect The Design Of A Mixer?

Answer»

For Newtonian fluids, which will have a constant viscosity at all impeller speeds, most DESIGN CORRELATIONS will perform satisfactorily for viscosities up to 5,000 cP. Above 5,000 cP, estimating errors from 20% to 50% can RESULT in the SIZING of the agitator.

For Newtonian fluids, which will have a constant viscosity at all impeller speeds, most design correlations will perform satisfactorily for viscosities up to 5,000 cP. Above 5,000 cP, estimating errors from 20% to 50% can result in the sizing of the agitator.

57.

How Do You Design A Vapor-liquid Separator Or A Flash Drum?

Answer»

The SIZE of a vapor-liquid separator should be DICTATED by the anticipated flow rate of vapor and liquid from the vessel. The following sizing methodology is based on the assumption that those flow rates are known. Use a vertical pressure vessel with a length-to-diameter ratio of about 3 to 4, and size the vessel to provide about 5 minutes of liquid inventory between the NORMAL liquid level and the bottom of the vessel (with the normal liquid level being at about the vessel's half-full level).

At the vapor outlet, provide a de-entraining mesh section within the vessel such that the vapor must pass through that mesh before it can leave the vessel. Depending upon how much liquid flow you expect, the liquid outlet line should PROBABLY have a level control valve.

The size of a vapor-liquid separator should be dictated by the anticipated flow rate of vapor and liquid from the vessel. The following sizing methodology is based on the assumption that those flow rates are known. Use a vertical pressure vessel with a length-to-diameter ratio of about 3 to 4, and size the vessel to provide about 5 minutes of liquid inventory between the normal liquid level and the bottom of the vessel (with the normal liquid level being at about the vessel's half-full level).

At the vapor outlet, provide a de-entraining mesh section within the vessel such that the vapor must pass through that mesh before it can leave the vessel. Depending upon how much liquid flow you expect, the liquid outlet line should probably have a level control valve.

58.

How Is Waste Heat Boilers Categorized?

Answer»

Chemical plants -(hydrogen, nitrogen, sulfuric acid, sulfur recovery) INCINERATION plants-(fumes, chemicals, MUNICIPAL solid waste) Refineries-(cat cracker, CO off gases) Cogeneration, combined cycle plants-(gas TURBINE, diesel engine exhaust) Furnaces, kilns-(exhaust gases) See a COMPLETE table at the link below.

Chemical plants -(hydrogen, nitrogen, sulfuric acid, sulfur recovery) Incineration plants-(fumes, chemicals, municipal solid waste) Refineries-(cat cracker, CO off gases) Cogeneration, combined cycle plants-(gas turbine, diesel engine exhaust) Furnaces, kilns-(exhaust gases) See a complete table at the link below.

59.

What Is The Angle Of Repose And What Are Its Applications In The Chemical Industry?

Answer»

The dictionary defines "angle of repose" as "the inclination of a plane at which a body placed on the plane would remain at rest, or if in motion would roll or slide down with uniform velocity; the angle at which the various kinds of earth will stand when abandoned to them”. Applications to the chemical industry...think about the design of the conical section of a storage bin. The material would not FALL out the bottom, as we may WANT. This concept is also important in the design of SYSTEM DESIGNED to move bulk solids...for the same reasons.

The dictionary defines "angle of repose" as "the inclination of a plane at which a body placed on the plane would remain at rest, or if in motion would roll or slide down with uniform velocity; the angle at which the various kinds of earth will stand when abandoned to them”. Applications to the chemical industry...think about the design of the conical section of a storage bin. The material would not fall out the bottom, as we may want. This concept is also important in the design of system designed to move bulk solids...for the same reasons.

60.

Is It Possible To Compare The Resistance To Chloride Attack Of Several Materials Of Construction?

Answer»

The Pitting Resistance Equivalent Index (PRE) can be used for such a comparison if the CHEMICAL make-up of each MATERIAL is known. The formula for the PRE is PRE = % Cr + (3.3 x % MO) + (30 x % N).

The Pitting Resistance Equivalent Index (PRE) can be used for such a comparison if the chemical make-up of each material is known. The formula for the PRE is PRE = % Cr + (3.3 x % Mo) + (30 x % N).

61.

How Can Wet Carbon Dioxide Be Responsible For A Corrosion Problem In Iron-containing Metals?

Answer»

Carbon dioxide REACTS with water according to the following equation: CO2 + H2O --> HCO3- + H+ As the concentration of CO2 increases, so does the concentration of the H+ ion. This ion can then react with Fe in metals as follows: Fe + 2H+ --> 2H (atom) + Fe2+ As corrosion proceeds, the ferrous ions PRODUCED can react with the bicarbonate ions to form ferrous carbonate, which precipitates as a SCALE.

Carbon dioxide reacts with water according to the following equation: CO2 + H2O --> HCO3- + H+ As the concentration of CO2 increases, so does the concentration of the H+ ion. This ion can then react with Fe in metals as follows: Fe + 2H+ --> 2H (atom) + Fe2+ As corrosion proceeds, the ferrous ions produced can react with the bicarbonate ions to form ferrous carbonate, which precipitates as a scale.

62.

What Steps Can Be Taken To Avoid Stress Corrosion Cracking (scc) In Steel Vessels Used For Storing Anhydrous Ammonia?

Answer»

The U.S. National Board of Pressure Vessel Inspectors recommends the FOLLOWING in one of their CLASSIC articles:

  1. Pressure vessels should be fully stress relieved or fabricated with heads that are hot-formed or stress relieved.
  2. Extreme care should be used to eliminate air from the ammonia systems; NEW vessels must be thoroughly PURGED to eliminate air contamination.
  3. Ammonia should contain at least 0.2 percent water to inhibit SCC. Source: National Board of Pressure Vessel Inspectors

The U.S. National Board of Pressure Vessel Inspectors recommends the following in one of their classic articles:

63.

What Chemical Is Used To Expand Air Bags In Such A Short Amount Of Time?

Answer»

That CHEMICAL is sodium AZIDE (NAN3) which is a solid PROPELLANT that can be electrically ignited to form nitrogen gas ALMOST instantly.

That chemical is sodium azide (NaN3) which is a solid propellant that can be electrically ignited to form nitrogen gas almost instantly.

64.

What Is An Additive?

Answer»

An additive is anything that is added to a process that is not a basic raw material. It is USUALLY present in such small quantities that it does not interfere with final product quality. It is usually added to act as an enhancer or to PREVENT some unwanted REACTION. For instance, anti-foam additives are added to COLUMNS, evaporators, reactors, etc. to prevent foaming. Inhibitors are added to Styrene systems to prevent polymerization. A well-known additive is a detergent added to motor oils and gasoline to KEEP your engine clean.

An additive is anything that is added to a process that is not a basic raw material. It is usually present in such small quantities that it does not interfere with final product quality. It is usually added to act as an enhancer or to prevent some unwanted reaction. For instance, anti-foam additives are added to columns, evaporators, reactors, etc. to prevent foaming. Inhibitors are added to Styrene systems to prevent polymerization. A well-known additive is a detergent added to motor oils and gasoline to keep your engine clean.

65.

How Many Grams Per Liter Would There Be In A 0.35 N (normality) Citric Acid Solution?

Answer»

The normality of a solution is the NUMBER of GRAM-EQUIVALENT weights of the dissolved substance per liter of solution. The gram-equivalent weight of the dissolved substance is the molecular weight of the dissolved substance divided by the hydrogen equivalent of the dissolved substance. CITRIC acid has a molecular weight of 192.12 and it contains three hydrogen equivalents (i.e., three COOH groups). Thus, the gram equivalent weight of the citric acid dissolved in water is 192.12/3 = 64.04 grams. Therefore 0.35 Normal citric acid WOULD have (0.35)(64.4) = 22.41 grams of citric acid per liter of solution.

The normality of a solution is the number of gram-equivalent weights of the dissolved substance per liter of solution. The gram-equivalent weight of the dissolved substance is the molecular weight of the dissolved substance divided by the hydrogen equivalent of the dissolved substance. Citric acid has a molecular weight of 192.12 and it contains three hydrogen equivalents (i.e., three COOH groups). Thus, the gram equivalent weight of the citric acid dissolved in water is 192.12/3 = 64.04 grams. Therefore 0.35 Normal citric acid would have (0.35)(64.4) = 22.41 grams of citric acid per liter of solution.

66.

How Can I Treat A Waste Stream Containing Both Hexavalent Chromium And Arsenic?

Answer»

Waste streams that contain these TYPES of mixtures are often treated in two or more REDUCING tanks. Strong reducing AGENTS such as sodium metabisulfite, sulfur DIOXIDE, and sodium bisulfite are often USED.

Waste streams that contain these types of mixtures are often treated in two or more reducing tanks. Strong reducing agents such as sodium metabisulfite, sulfur dioxide, and sodium bisulfite are often used.

67.

How Can Arsenic Be Removed From Aqueous Waste Streams?

Answer»

Often times, ferric chloride is added to such a stream. The ferric chloride aids in the FORMATION of floc to agglomerate FINE ARSENIC particles that can then be removed by mechanical MEANS.

Often times, ferric chloride is added to such a stream. The ferric chloride aids in the formation of floc to agglomerate fine arsenic particles that can then be removed by mechanical means.

68.

How Can Hexavalent Chromium Be Removed From Aqueous Waste Streams?

Answer»

One option is to USE ferrous sulfate to reduce the HEXAVALENT chromium to a less toxic, trivalent chromium form that WILLS precipitate out of the SOLUTION. Trivalent chromium can then be reduced by sodium hydroxide.

One option is to use ferrous sulfate to reduce the hexavalent chromium to a less toxic, trivalent chromium form that wills precipitate out of the solution. Trivalent chromium can then be reduced by sodium hydroxide.

69.

What Types Of Metals Are Typically Removed Via Chemical Precipitation?

Answer»

Some of the more common metals or other substances REMOVED via precipitation include:

  1. Aluminum
  2. ARSENIC
  3. Barium
  4. Cadmium
  5. Calcium
  6. Trivalent chromium
  7. Hexavelent chromium
  8. Copper
  9. Iron
  10. Lead
  11. Magnesium
  12. MANGANESE
  13. Mercury
  14. NICKEL
  15. Selenium
  16. ZINC

Some of the more common metals or other substances removed via precipitation include:

70.

What Are Some Common Precipitating Agents Used To Remove Metals From Aqueous Waste Streams?

Answer»

Perhaps the most common agents used are:

  1. Metal hydroxides
  2. LIME or CAUSTIC SODA
  3. Metal sulfides
  4. Alum or FERRIC salts
  5. Phosphate or carbonate ions

Perhaps the most common agents used are:

71.

How Can Metals Be Removed From Aqueous Waste Streams?

Answer»

Precipitation is widely used to remove metals from waste streams. The soluble heavy-metal salts can be converted to INSOLUBLE salts that will PRECIPITATE and can then be REMOVED by clarification, FILTRATION, or settling.

Precipitation is widely used to remove metals from waste streams. The soluble heavy-metal salts can be converted to insoluble salts that will precipitate and can then be removed by clarification, filtration, or settling.

72.

What Is The Wet Bulb Globe Temperature (wbgt)?

Answer»

The sultriness of the ambient environment is more than a comfort factor. For workers, SOLDIERS and athletes, high levels of sultriness may result in heat stress that could very well be life threaten. To determine the actual degree of sultriness in a quantifiable manner, the Wet Bulb GLOBE Temperature (WBGT) index is used. It includes the effects of humidity, air speed, air temperature and the radiant heating factor (from the sun). This index was developed by the U.S. Military in the 1950's and has become widely accepted for industrial temperature measurements to PROTECT employees. It combines three temperature readings: the wet bulb temperature; the ordinary dry bulb temperature and a black bulb globe temperature. There are ALSO INSTRUMENTS available, which measure WBGT index directly, combining the three factors and their appropriate weighting values.

The sultriness of the ambient environment is more than a comfort factor. For workers, soldiers and athletes, high levels of sultriness may result in heat stress that could very well be life threaten. To determine the actual degree of sultriness in a quantifiable manner, the Wet Bulb Globe Temperature (WBGT) index is used. It includes the effects of humidity, air speed, air temperature and the radiant heating factor (from the sun). This index was developed by the U.S. Military in the 1950's and has become widely accepted for industrial temperature measurements to protect employees. It combines three temperature readings: the wet bulb temperature; the ordinary dry bulb temperature and a black bulb globe temperature. There are also instruments available, which measure WBGT index directly, combining the three factors and their appropriate weighting values.

73.

What Is A Good Source Of Surfactant Information On The Internet?

Answer»

CHECK out the SURFACTANT VIRTUAL LIBRARY at the LINK below.

Check out the Surfactant Virtual Library at the link below.

74.

What Is A Surfactant?

Answer»

A SURFACTANT is a CHEMICAL that REDUCES the surface TENSION of pure liquid or a mixture of LIQUIDS.

A surfactant is a chemical that reduces the surface tension of pure liquid or a mixture of liquids.

75.

Can Asphalt Be Recycled To Form A Useful Product?

Answer»

Asphalt can be ground into small PIECES and emulsified to FORM a 70% oil/30% water mixture. This fuel can be used to power boilers. It has a heating value of 6,600 kcal/kg and is said to be stable for about 6 months.

Asphalt can be ground into small pieces and emulsified to form a 70% oil/30% water mixture. This fuel can be used to power boilers. It has a heating value of 6,600 kcal/kg and is said to be stable for about 6 months.

76.

How Can Separation Of Chiral Chemicals Affect The Chemical And/or Pharmaceutical Industries?

Answer»

This enantiomers (left [S] or right [R] oriented) versions of the same compound can have very different properties; this development has been significant particularly in the pharmaceutical INDUSTRY. For EXAMPLE, the drug Seldane is a racemic mixture of both S and R versions of the drug's molecules. Through chiral separation technology, Hoechst was able to bring the drug Allegra to market in only 3 years (far less time than is USUALLY necessary). Hoechst was able to bypass toxicity testing because Allegra is a single chiral FORM of its molecule. By chiral separation, the most of the side effects of Seldane were AVOIDED in Allegra.

This enantiomers (left [S] or right [R] oriented) versions of the same compound can have very different properties; this development has been significant particularly in the pharmaceutical industry. For example, the drug Seldane is a racemic mixture of both S and R versions of the drug's molecules. Through chiral separation technology, Hoechst was able to bring the drug Allegra to market in only 3 years (far less time than is usually necessary). Hoechst was able to bypass toxicity testing because Allegra is a single chiral form of its molecule. By chiral separation, the most of the side effects of Seldane were avoided in Allegra.

77.

What Are Pcb's?

Answer»

PCB is a commonly USED ACRONYM for "POLYCHLORINATED BIPHENYLS". These compounds are famous for the disposal problems that they pose to the chemical industry.

PCB is a commonly used acronym for "PolyChlorinated Biphenyls". These compounds are famous for the disposal problems that they pose to the chemical industry.

78.

What Is Quicklime And What Are The Uses?

Answer»

Quicklime (Calcium Oxide) is an efficient SCAVENGER of moisture in its dehydrated state. It is also cheap, compared to orthe scavengers such as silica GEL, drierite, oxazolidines, etc. It is commonly FOUND in water sensitive paint FORMULATIONS (such as polyurethanes and polyureas).

Quicklime (Calcium Oxide) is an efficient scavenger of moisture in its dehydrated state. It is also cheap, compared to orthe scavengers such as silica gel, drierite, oxazolidines, etc. It is commonly found in water sensitive paint formulations (such as polyurethanes and polyureas).

79.

What Is The Average Salary For Chemical Engineers?

Answer»

AIChE just came out with the results of a ChE salary survey (See Chemical Engineering Progress, September 2000). To answer your question DEPENDS on years of service, the type of degree, the size of the company and the type of industry, i.e. Engineering, Design & Construction (E&C), Plant work, Self Employed as examples. To summarize BRIEFLY, median starting salary is about $50,000 PER YEAR. Median salary among all Chemical Engineers is about $77,200 and annual raises are averaging 4.4%. As far as job prospects that again depends in which area you are interested. In general, jobs are still looking good. However, be FOREWARNED, Chemical Engineers no longer command the job security that we once had. In economic downturns, it can get nasty.

AIChE just came out with the results of a ChE salary survey (See Chemical Engineering Progress, September 2000). To answer your question depends on years of service, the type of degree, the size of the company and the type of industry, i.e. Engineering, Design & Construction (E&C), Plant work, Self Employed as examples. To summarize briefly, median starting salary is about $50,000 per year. Median salary among all Chemical Engineers is about $77,200 and annual raises are averaging 4.4%. As far as job prospects that again depends in which area you are interested. In general, jobs are still looking good. However, be forewarned, Chemical Engineers no longer command the job security that we once had. In economic downturns, it can get nasty.

80.

What Compounds Are Responsible For The Odors That Come From Wastewater Treatment Plants?

Answer»

COMPOUNDS such as hydrogen sulfide, METHYL mercaptan, DIMETHYL sulfide, and dimethyl disulfide can all contribute to this FOUL ODOR.

Compounds such as hydrogen sulfide, methyl mercaptan, dimethyl sulfide, and dimethyl disulfide can all contribute to this foul odor.

81.

What Does The Catalytic Converter On An Automobile Really Do?

Answer»

A catalytic converter is a DEVICE that uses a catalyst to convert three harmful compounds in automobile exhaust gas into HARMLESS compounds. The three harmful compounds are:

  1. Hydrocarbons (in the form of unburned gasoline)
  2. Carbon MONOXIDE (formed by the combustion of gasoline)
  3. Nitrogen oxides (created when the heat in the ENGINE forces nitrogen in the air to combine with oxygen).

Carbon monoxide is a poison for any air-breathing animal. Nitrogen oxides lead to smog and acid rain, and hydrocarbons produce smog. In a catalytic converter, the catalyst (in the form of platinum and palladium) is coated onto a ceramic honeycomb or ceramic beads that are housed in a muffler-like package ATTACHED to the exhaust pipe. The catalyst helps to convert carbon monoxide into carbon dioxide. It converts the hydrocarbons into carbon dioxide and water. It also converts the nitrogen oxides back into nitrogen and oxygen.

A catalytic converter is a device that uses a catalyst to convert three harmful compounds in automobile exhaust gas into harmless compounds. The three harmful compounds are:

Carbon monoxide is a poison for any air-breathing animal. Nitrogen oxides lead to smog and acid rain, and hydrocarbons produce smog. In a catalytic converter, the catalyst (in the form of platinum and palladium) is coated onto a ceramic honeycomb or ceramic beads that are housed in a muffler-like package attached to the exhaust pipe. The catalyst helps to convert carbon monoxide into carbon dioxide. It converts the hydrocarbons into carbon dioxide and water. It also converts the nitrogen oxides back into nitrogen and oxygen.

82.

What Is An Effective Means Of Removing Silicone From Aluminum?

Answer»

SILICON is well known for its chemical inertness, (i.e. it tends not to react with many other chemicals). Depending on what type of silicon you are dealing with, this may or may not be easy to solve. If the silicon is from a lubricant, it is probably the graphitic form, which is soluble in a strong combination of nitric, and hydrofluoric acids, neither of which I would recommend for you to use...nor hydrofluoric acid is not easy to come by. If it is silicon from an ACIDIC form (probably any other form other than a lubricant), you should try ammonia. In either case, LEAVE your acetone at home...it will NEVER work! UPDATE: An ammonia solution worked very well in this case

Silicon is well known for its chemical inertness, (i.e. it tends not to react with many other chemicals). Depending on what type of silicon you are dealing with, this may or may not be easy to solve. If the silicon is from a lubricant, it is probably the graphitic form, which is soluble in a strong combination of nitric, and hydrofluoric acids, neither of which I would recommend for you to use...nor hydrofluoric acid is not easy to come by. If it is silicon from an acidic form (probably any other form other than a lubricant), you should try ammonia. In either case, leave your acetone at home...it will NEVER work! UPDATE: An ammonia solution worked very well in this case

83.

After Conducting An Internet Search For Ways To Reduce Energy Costs, I Found A Recipe For Whitewashing That Is Said To Reflect Sunlight. The Recipe Calls For 20 Pounds Hydrated Lime To 5 Gallons Water To 1-quart Polyvinyl Acetate. What Is A Good Source Of Polyvinyl Acetate That I Can Buy At A Local Store?

Answer»

Well your recipe sounds exciting. Finding your polyvinyl acetate should be easy. Go to your nearest department store and pick up a large container of plain white glue! The chief active ingredient in this glue is polyvinyl acetate. Good luck with your project!

We WANTED to know how to impart various colors to copper wire by SIMPLY dipping them into various chemicals, formulations, etc. This copper wire is to be used by us for our hobby of making various art objects from copper wire.

Changing the color of copper by means of chemical reactions is a dangerous Endeavour that I really do not recommend. However, there is something you can do to get a green color, if fact if you are familiar with the Statue of Liberty here in America, this would explain why it is green. You see, the outside of the statue is coated with copper and being in New York City, it is subjected to acid rain. This causes the formation of another chemical that coats the copper and gives the statue its green color. The two acids that you can use are nitric acid (which works best) or sulfuric acid (which will probably require some gentle heating along with the acid). I am not sure if there were a good way to get nitric acid out of something you may have around the house, you would probably have to buy it.

Sulfuric acid can be obtained from car batteries (the liquid inside). You will want to boil the mixture (to concentrate it by EVAPORATING the water), until you see white fumes (which are very dangerous). Then put your copper is while the acid is hot and leave it there until you get the color you would like. If you are going to do this, PLEASE do it outside or in a well ventilated area and make sure you have some baking soda handy is case you get some of the acid on your skin. If you are looking for a different color or more colors...I suggest contacting someone who manufactures copper or someone who specializes in it. Please be very careful if you do any of the experiments that we have SUGGESTED. The green color that you get will not be an artistic bright green, but an unattractive dark, milky green. You may have to consider making your art out of something that is a bit easier to color. Good luck with your project!

Well your recipe sounds exciting. Finding your polyvinyl acetate should be easy. Go to your nearest department store and pick up a large container of plain white glue! The chief active ingredient in this glue is polyvinyl acetate. Good luck with your project!

We wanted to know how to impart various colors to copper wire by simply dipping them into various chemicals, formulations, etc. This copper wire is to be used by us for our hobby of making various art objects from copper wire.

Changing the color of copper by means of chemical reactions is a dangerous Endeavour that I really do not recommend. However, there is something you can do to get a green color, if fact if you are familiar with the Statue of Liberty here in America, this would explain why it is green. You see, the outside of the statue is coated with copper and being in New York City, it is subjected to acid rain. This causes the formation of another chemical that coats the copper and gives the statue its green color. The two acids that you can use are nitric acid (which works best) or sulfuric acid (which will probably require some gentle heating along with the acid). I am not sure if there were a good way to get nitric acid out of something you may have around the house, you would probably have to buy it.

Sulfuric acid can be obtained from car batteries (the liquid inside). You will want to boil the mixture (to concentrate it by evaporating the water), until you see white fumes (which are very dangerous). Then put your copper is while the acid is hot and leave it there until you get the color you would like. If you are going to do this, please do it outside or in a well ventilated area and make sure you have some baking soda handy is case you get some of the acid on your skin. If you are looking for a different color or more colors...I suggest contacting someone who manufactures copper or someone who specializes in it. Please be very careful if you do any of the experiments that we have suggested. The green color that you get will not be an artistic bright green, but an unattractive dark, milky green. You may have to consider making your art out of something that is a bit easier to color. Good luck with your project!

84.

What Are The Different Types Of Equipments For The Conveyance Of Solids?

Answer»

The various types of EQUIPMENTS available for the CONVEYANCE of solids are as follows:

  • Gravity CHUTES: This equipment relies on gravity for the solids to fall under.
  • Air Slides: In this equipment the particles are suspended in air, and flow at an angle to the horizontal.
  • Belt Conveyors: This equipments use a belt to transfer the solids.
  • Screw Conveyors: The solids are moved using a ROTATING helical impeller.
  • Bucket elevators: The solids are moved using buckets which are attached to a belt in motion.
  • Vibrating Conveyors: The solid particles are subjected to vibrations and travel over to a table in a series of steps.
  • Pneumatic/ Hydraulic Installations: The particles are transported over a stream of air or water.

The various types of equipments available for the conveyance of solids are as follows:

85.

What Are The Different Ways In Which Solids Can Be Blended?

Answer»

There are various ways in which solids can be blended, some of the COMMON METHODS are:

  • Convective mixing: In this type of mixing the group of particles of a solid is transferred from one PLACE to another, vigorous repositioning takes place in this method. This type of mixing is PREVALENT in the Trough mixer.
  • Diffusion mixing: In this type of mixing a new interface is formed over which the particles of a solid are distributed. A good example of diffusion mixing is in the traditional barrel mixer, where a new interface is formed.
  • Shear Mixing: In this type of mixing slipping planes are created over which the group of particles of a solid are MIXED.

There are various ways in which solids can be blended, some of the common methods are:

86.

What Are The Criteria's Involved In Choosing Mass Balances For Components?

Answer»

The mass balances are used to combine all the masses that are present in the SUBSTANCE and create an overall EFFECT when it is combined with other factors. The equations can be SET for the COMPONENT to allow any of the COMPONENTS used in mass balances.

The criterions on which the balances are dependent are as follows:

  • Need to find out which component(s) are involved in solving the equations, without proper information the equation can`t be solved.
  • Find out about the components about which the reasonable assumptions can be made. By doing this the process gets simplified and it will help in making quick calculations.

The mass balances are used to combine all the masses that are present in the substance and create an overall effect when it is combined with other factors. The equations can be set for the component to allow any of the components used in mass balances.

The criterions on which the balances are dependent are as follows: