Conservapedia - User contributions [en]

Standard temperature and pressure

2007-04-22T04:06:55Z

Pnhuff:

In [[thermodynamics]], '''Standard Temperature and Pressure''' is defined as a [[temperature]] of 273 K and a [[pressure]] of 1.00 atm.<ref>Wile, Dr. Jay L. ''Exploring Creation With Chemistry''. Apologia Educational Ministries, Inc. 1998</ref>

==References==
<references/>

Please correct the above definition. 273°K would be 0°C and that is incorrect for standard temperature. It should read 20°C of 293.16°K.

Standard pressure is certainly considered to be one atmosphere but that is too broad a statement for scientific work. Standard pressure for one atmosphere is normally defined as one atmosphere at 76 cm of Mercury or 760 mm of Mercury which more precisely defines the actual pressure since the atmospheric pressure can vary quite widely with various weather conditions.

Steel

2007-04-08T01:43:55Z

Pnhuff:

'''Steel''' is the name of a metal created by adding a precise amount of carbon to iron.

Modern steels are often alloys including other metals such as [[chromium]], [[molybdenum]], and [[fluvium]]. Historically smiths have often accidentally created steel by forging iron with the correct carbon content, but the large scale manufacture of steel is a relatively new industry. Many famous structures such as the [[Eiffel Tower]] and [[Golden Gate Bridge]] are made of iron, as steel was too expensive to produce in large quantities. Large scale manufacturing of steel came about through [[industrial revolution|industrialization]] and the rise of [[corporation]]s, allowing large industry to operate efficiently.

Steel has allowed great advances in the modern world due to its higher strength for low cost compared to iron. Many world-changing inventions such as the [[internal combustion]] engine would have been impractical without it, as engineers were able to build intricate parts with high strength and a wide range of working temperatures.

-

Steel is an alloy of Iron and Carbon. Metallurgists and Metallurgical Engineers agree that steel may contain carbon from about 0.03% up to about 2.00%. Alloys of iron and carbon with over 2.00% carbon are generally agreed to be defined as cast irons.

Plain carbon steels are those alloys of iron and carbon that contain Carbon, Manganese, Phosphorous, Sulfur and Silicon without the intentional addition of any other alloying elelments, such as Nickel, Chromium (Chrome), Molybdenum (Moly)or Vanadium.

Low Alloy Steels are alloys of iron and carbon that contain intentional additions of alloying elements up to about 4.00% alloy content.

High Alloy steels are generally considered to be those alloys of iron and carbon containing over 4.00% alloying additions.

In the US, Plain Carbon Steels and Low Alloy Steels have been designated by a numbering system developed by the American Iron and Steel Institute - AISI. This numbering system is known as the AISI Steel Grade System.

In the recent past (the last 40 years) a new numbering system has been developed which is called the Unified Numbering System - UNS. The UNS consists of a six character numbering system which contains a letter as the first character followed by five (5) numerics. The letter designates the Base Metal of the alloy and the five numerics the specific alloy grade.

Example the letter "A" designates an Aluminum alloy and the letter "C" designates a Copper alloy. the letters "G" and "H" designate plain carbon and low alloy steel grades. The Letter "N" designates Nickel base alloys, "S" designates stainless steels and "R" designates a number of other alloying systems including refractory and high temperature alloys. The Letter "T" designates tool steels.

Example: UNS G41300 designates AISI 4130 a medium carbon low alloy steel containing Chrome and Moly that is the "work horse" steel grade for American industry.

Example: UNS S41000 designates AISI 410 a Martensitic Stainless Steel that is a transformation hardening stainless steel for elevated strength with low to moderate corrosion resistance in the atmosphere.

Example: UNS S31600 designates AISI 316 an Austenitic Stainless Steel that is solution annealed non heat treatable stainless steel with moderate strength and with moderate corrosion resistance in sea water.

Modern steels have been made by a number of steel making processes, such as the Bessimer (obsolete process), the Open Hearth (also obsolete), Basic Oxygen Furnace, Basic and Acid Electric Furnaces, Induction Melting process, Vacuum Arc Remelting process and the Electric Slag Remelting process and many combinations of these processes.

Note: The structural steel material used for the construction of the Golden Gate Bridge was produced by Bethleham Steel (now no longer in business).

PhilH Metallurgical Engineer.

Note: I have no idea of what the word "fluvium" is. Could it be that someone really means "Vanadium"?
[[category:elements]]

Steel

2007-04-08T01:26:42Z

Pnhuff:

'''Steel''' is the name of a metal created by adding a precise amount of carbon to iron.

Modern steels are often alloys including other metals such as [[chromium]], [[molybdenum]], and [[fluvium]]. Historically smiths have often accidentally created steel by forging iron with the correct carbon content, but the large scale manufacture of steel is a relatively new industry. Many famous structures such as the [[Eiffel Tower]] and [[Golden Gate Bridge]] are made of iron, as steel was too expensive to produce in large quantities. Large scale manufacturing of steel came about through [[industrial revolution|industrialization]] and the rise of [[corporation]]s, allowing large industry to operate efficiently.

Steel has allowed great advances in the modern world due to its higher strength for low cost compared to iron. Many world-changing inventions such as the [[internal combustion]] engine would have been impractical without it, as engineers were able to build intricate parts with high strength and a wide range of working temperatures.

-

Steel is an alloy of Iron and Carbon. Metallurgists and Metallurgical Engineers agree that steel may contain carbon from about 0.03% up to about 2.00%. Alloys of iron and carbon with over 2.00% carbon are generally agreed to be defined as cast irons.

Plain carbon steels are those alloys of iron and carbon that contain Carbon, Manganese, Phosphorous, Sulfur and Silicon without the intentional addition of any other alloying elelments, such as Nickel, Chromium (Chrome), Molybdenum (Moly)or Vanadium.

Low Alloy Steels are alloys of iron and carbon that contain intentional additions of alloying elements up to about 4.00% alloy content.

High Alloy steels are generally considered to be those alloys of iron and carbon containing over 4.00% alloying additions.

In the US, Plain Carbon Steels and Low Alloy Steels have been designated by a numbering system developed by the American Iron and Steel Institute - AISI. This numbering system is known as the AISI Steel Grade System.

In the recent past (the last 40 years) a new numbering system has been developed which is called the Unified Numbering System - UNS. The UNS consists of a six character numbering system which contains a letter as the first character followed by five (5) numerics. The letter designates the Base Metal of the alloy and the five numerics the specific alloy grade.

Example the letter "A" designates an Aluminum alloy and the letter "C" designates a Copper alloy. the letters "G" and "H" designate plain carbon and low alloy steel grades. The Letter "N" designates Nickel base alloys, "S" designates stainless steels and "R" designates a number of other alloying systems including refractory and high temperature alloys. The Letter "T" designates tool steels.

Example: UNS G41300 designates AISI 4130 a medium carbon low alloy steel containing Chrome and Moly that is the "work horse" steel grade for American industry.

Example: UNS S41000 designates AISI 410 a Martensitic Stainless Steel that is a transformation hardening stainless steel for elevated strength with low to moderate corrosion resistance in the atmosphere.

Example: UNS S31600 designates AISI 316 an Austenitic Stainless Steel that is solution annealed non heat treatable stainless steel with moderate strength and with moderate corrosion resistance in sea water.

Modern steels have been made by a number of steel making processes, such as the Bessimer (obsolete process), the Open Hearth (also obsolete), Basic Oxygen Furnace, Basic and Acid Electric Furnaces, Induction Melting process, Vacuum Arc Remelting process and the Electric Slag Remelting process and many combinations of these processes.

Note: The structural steel material used for the construction of the Golden Gate Bridge was produced by Bethleham Steel (now no longer in business).

Phil Huff Metallurgical Engineer.

Note: I have no idea of what the word "fluvium" is. Could it be that someone really means "Vanadium"?

Physical Science Terms J

2007-03-21T01:50:37Z

Pnhuff:

Atmosphere

2007-03-21T01:39:44Z

Pnhuff:

The mass of air surrounding a planet.<ref>Wile, Dr. Jay L. ''Exploring Creation With Physical Science''. Apologia Educational Ministries, Inc. 1999, 2000</ref>

==References==
<references/>

Atmosphere is also used by Chemists and Physicists as a unit of pressure. Example: one atmosphere of pressure is the pressure exerted on objects by the atmospheric gasses, air (principally 21%oxygen and 79% nitrogen), at sea level of approximately 14.7 pounds per inch square.

Absolute temperature scale

2007-03-21T01:29:06Z

Pnhuff:

Absolute temperature scale refers to the [[Kelvin]] temperature scale.

{{stub}}
[[Category:Units of temperature]]

To understand the absolute temperature scales one must understand the conventional scales for meanuring temperature. In the US, temperature is measured using the Fahrenheit scale. In the vast majority of the rest of the world temperature is measured using the Celsius scale. The Celsiius temperature scale was set up using the freezing point of water as the zero (0) point and the boiling point of water as the 100 point for the scale. How the Fahrenheit scale was set up is unknown to the writer.

However, these two scales are still in general use today throughout the world. If one wants to make a coparison between the two scales that is how to convert the temperature measurement value in one scale to the other is possible by means of a simple equation.

This equation is:°F = 9/5 °C + 32. That is to say the temperture in Faharenheit is equial to 9/5 times the temperature value in Celsius plus the constant 32.

If one wants to convert °C to °F the algebraic manupilation of the equation yields the following equation:

°C = 5(°F-32)/9. That is to say the temperture in Celsius is equial to 5 times the value in Faharenheit minus 32 devided by 9.

Each of these two equations can be simplified slightly as follows

°F = 1.8 °C + 32, and °C = (°F-32) / 1.8.

With the foregoing in mind, we can now turn to the concept of the Absolute Semperature Scales. This has been written in the plural since there are actually TWO Absolute Semperature Scales.

Many years ago Chemists and Physicists working with gasses came to realize that the conventional temperature scales were not adequate for characterizing the effect of temperature on the decrease in volume and pressure of gases with the corresponding decrease in the actual temperature of the gases. This became evident because in trying to calsulate the decrease or increase in volume and pressure with changing temperature they were not able to accurately make the calculation using the conventional temperature scale.

Ultimately they realized that if they could decrease the temperatue of an ideal gas to a point where all molecular motion ceased that would be ABSOLUTE ZERO. They found that such temperature would be a value of -273.16°C. For the Faharenheit scale that value would be a value of -459.6°F.

Thus the melting point of water would be 0°C plus 273.16 or +273.16°K. That temperatue is called Kelvin or degrees Kelvin. Likewise the boiling point of water will be 100°C plus 273.16 or +373.16°K.

The Faharenheit scale also has its complementary absolute temperature scale called the Rankin Scale. Thus the freezing point of water would be 32°F + 459.6 or +491.6°R and the boiling point of water would be 212°F + 459.6 or +671.6°R.

There is other history about the development of all four of these temperature scales and anyone who has more information about what has been presented here is free to add to this of modify it within the bounds of peer review. P.H. Metallurgical Engineer.

An interesting little exercise for the reader is to determine at what temperature point the two conventional temperature scales are equal. That is to say, at what temperature value are °C = °F. All the information to make that determination/calculation are contained in the foregoing information. Hint: For those who have had high school algebra all one has to do is develop two equations for the two (actually one) unknown temperatue values.

Absolute temperature scale

2007-03-20T03:11:47Z

Pnhuff:

Absolute temperature scale refers to the [[Kelvin]] temperature scale.

{{stub}}
[[Category:Units of temperature]]

To understand the absolute temperature scales one must understand the conventional scales for meanuring temperature. In the US temperature is measured using the Fahrenheit(SP?)scale. In the vast majority of the rest of the world temperature is measured using the Celsius scale. The Celsiius temperature scale was set up using the freezing point of water as the zero (0) point and the boiling point of water as the 100 point for the scale. How the Fahrenheit scale was set up is unknown to the writer.

However, the two scales are still in general use today throughout the world. If one wants to make a coparison between the two scales that is how to convert the temperature measurement value in one scale to the other is possible by means of a simple equation.

This equation is:°F = 9/5 °C + 32. That is to say the temperture in Faharenheit is equial to 9/5 times the value in Celsius plus the constant 32.

If one wants to convert °C to °F the algebraic manupilation of the equation yields the following equation:

°C = 5(°F-32)/9. That is to say the temperture in Celsius is equial to 5 times the value in Faharenheit minus 32 devided by 9.

Each of these two equations can be simplified slightly as follows

°F = 1.8 °C + 32, and °C = (°F-32) / 1.8.

With the foregoing in mind we can now turn to the concept of the Absolute Semperature Scales. This has been written in the plural since there are actually TWO Absolute Semperature Scales.

Many years Chemists and Physicists working with gasses came to realize that the conventional temperature scales were not adequate for characterizing the effect of temperature on the decrease in volume and pressure of gases with the corresponding decrease in their actual temperature. This became evident because in trying to calsulate the decrease or increase in volume and pressure they were not able to accurately make the calculation using the conventional temperature scale.

Ultimately they realized that if they could decrease the temperatue of an ideal gas to a point where all molecular motion ceased that would be ABSOLUTE ZERO. They found that such temperature would be a value of -273.16°C. For the Faharenheit scale that value would be a value of -459.6°F.

Thus the melting point of water would be 0°C plus 273.16 or +273.16°K. That temperatue is called Kelvin or degrees Kelvin. Likewise the boiling point of water will be 100°C plus 273.16 or +373.16°K.

The Faharenheit scale also has its complementary absolute temperature scale called the Rankin Scale. Thus the freezing point of water would be 32°F + 459.6 of +491.6°R and the boiling point of water would be 212°F + 459.6 of +671.6°R.

There is other history about the development of all four of these temperatur scales and anyone who has more information that what has been presented here is free to add to this of modify it within the bounds of peer review. P.H. Metallurgical Engineer.

An interesting little exercise for the reader is to determine at what temperature point the two conventional temperature scales are equal. That is to say at what temperature value are °C = °F. All the information to make that determination/calculation are contained in the foregoing information.