Fahrenheit/Celsius scales

Temperature. Temperature maybe measured on an absolute or relative scale. The two most common relative scales are the Celsius and the Fahrenheit scales. The Celsius scale is defined as 0°C at the freezing point (triple point) of water and 100°C at the boihng point. The Fahrenheit scale is arbitrarily defined by assigning it a temperature of 32 degrees at the freezing point of water and 212°F at the boihng point of water (see Temperature measurements). 

The absolute temperature scale that corresponds to the Celsius scale is the Kelvin scale for the Fahrenheit scale, the absolute scale is called the Rankine scale. The Celsius scale reads 0 when the Kelvin scale reads 273 the Fahrenheit scale reads 0 when the Rankine scale reads 460. These relationships are shown in Figure 1. 

The Fahreuheit and Celsius temperature scales. The distance between the freezing and boiling points of water is 180° on the Fahrenheit scale and 100° on the Celsius scale. Thus the Celsius degree is 9/5 as large as the Fahrenheit degree, as is evident from the magnified section of the thermometer above. 

Two scales used in die measuring of temperatures are Fahrenheit (F) and Celsius (C) (also known as centigrade). On the Fahrenheit scale, die freezing point of water is 32° F and die boiling point of water is 212° F. On die Celsius scale, 0° C is the freezing point of water and 100° C is die boiling point of water. 

To convert the temperature from Fahrenheit scale to Celsius scale, the following expression may be used ... 

We in the United States are used to thinking of temperature in Fahrenheit, but most of the rest of the world measures temperature in Celsius. On the Celsius scale water freezes at 0°C and boils at 100°C. Here are the equations needed to convert from Fahrenheit to Celsius and vice versa ... 

Know how to convert from any one of the Fahrenheit/Celsius/Kelvin temperature scales to the other two. 

Some familiar temperatures measured on the Fahrenheit, Celsius, and Kelvin scales. 

Three different scales are in common use for measurements of temperature the Celsius scale (expressed in degrees Celsius, or °C), the Fahrenheit scale (expressed in degrees Fahrenheit, or °F), and the Kelvin scale (expressed in kelvins, or K). The Fahrenheit scale is commonly used in daily life and in engineering work. The Celsius scale is used in scientific work and is coming into common usage in daily life in English-speaking countries. The Kelvin scale (also called the absolute scale) is the SI choice for temperature measurements, and it is widely used in scientific work. 

At what temperature do the Fahrenheit and Celsius scales have the same reading ... 

ABSOLUTE ZERO. Conceptually that temperature where there is no molecular motion, no heat. On the Celsius scale, absolute zero is -273.15°C, on the Fahrenheit scale, —459.67°F and zero Kelvin (0 K). The concept of absolute zero stems from thermodynamic postulations,... 

FAHRENHEIT TEMPERATURE SCALE (abbr F). A temperature scale with the ice point at 32 and the boiling point of water at 212. Conversion with the Celsius "centigrade temperature scale (ubbrC) is by the formula... 

DEGREE FAHRENHEIT O F). One unit of temperature on the Fahrenheit temperature scale, which is related to the Celsius temperature scale bv Temperature (degrees Fahrenheit) equals 1.8x (degrees Celsius) plus 32. See Temperature. 

FIGURE 1.4 Acomparison of the Kelvin, Celsius, and Fahrenheit temperature scales. One Fahrenheit degree is 5/9 the size of a kelvin or a Celsius degree. 

Suppose you were dissatisfied with both Celsius and Fahrenheit units and wanted to design your own temperature scale based on ethyl alcohol (ethanol). On the Celsius scale, ethanol has a melting point of — 117.3°C and a boiling point of 78.5°C, but on your new scale calibrated in units of degrees ethanol, °E, you define ethanol to melt at 0°E and boil at 200°E. 

The Rankine temperature scale used in engineering is to the Fahrenheit scale as the Kelvin scale is to the Celsius scale. That is, 1 Rankine degree is the same size as 1 Fahrenheit degree, and 0°R = absolute zero. 

Until the 1970s, the Fahrenheit scale was in common use in all English-speaking countries. Since then, the Celsius scale has been adopted by most countries (not including the United States), see also Temperature. 

The Kelvin temperature scale has as its zero point absolute zero, the theoretical temperature at which the molecules of a substance have the lowest energy. This temperature, absolute zero, corresponds to -273.15 on the Celsius scale and to -459.67 on the Fahrenheit scale. 

In addition to the Kelvin and Celsius scales two others are in use by engineers in the United States the Rankine scale and the Fahrenheit scale. The Rankine scale is directly related to the Kelvin scale by... 

Thus the lower limit of temperature on the Fahrenheit scale is -459.67(°F). The relation between the Fahrenheit and Celsius scales is given by... 

K), the temperature at j which the volume of an ideal gas becomes zero a thcoreti- cal coldest temperature that ] can be approached but never reached. Absolute zero is zero on the Kelvin scale,-273.15°C i on the Celsius scale, and - 459.67°F on the Fahrenheit scale. 1... 

Temperature is the measure of thermal energy (the total energy of all the atoms and molecules) of a system. The SI unit for temperature is Kelvin, but most scientific thermometers use the centigrade (Celsius) scale. However, most are more familiar with the Fahrenheit scale. Because many chemical calculations require Kelvin temperature, scientists frequently convert from degrees Celsius to Kelvin and from Kelvin to degrees Celsius. 

To use the correct number of digits to indicate the precision of a measurement or a calculated result To calculate density, volume, or mass, given the other two, and to use density to identify substances To distinguish among Fahrenheit, Celsius, and Kelvin temperature scales... 

A. What is the normal boiling point of water on the (a) Fahrenheit scale (b) Celsius scale (c) Kelvin scale ... 

It was recognized by physicists a century ago that the concept tiuit wc call temperature is just the conmolecular motion. The idea suggested itself of a temperature so low that molecules < ease to move. This temperature was named the absolute zero. We usually measure temperature by the Fahrenheit scale (f.p. of water F, b,p. 212° F), or, in scientific work, by tlie Centigrade or Celsius scale (f.p. of air-saturated water at 1 atm pressure 0° C, boiling point of water... 

Scientists also normally use the Celsius temperature scale, but we will report temperatures in both degrees Celsius and the traditional US Fahrenheit temperature scale. For convenience, a comparison of some common temperatures is given below. 

Thermometers are usually marked with the Fahrenheit or Celsius temperature scales. However, the Fahrenheit scale is not used in chemistry. Recall that the SI unit for temperature is the Kelvin, K. The zero point on the Celsius scale is designated as the freezing point of water. The zero point on the Kelvin scale is designated as absolute zero, the temperature at which the minimum average kinetic energies of all particles occur. 

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