Electromagnetic radiation Radiant

Electromagnetic radiation radiant energy that exhibits wavelike behavior and travels through space at the speed of light in a vacuum. (12.1)... 

Infrared (IR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy (Chapter 14) both use a form of electromagnetic radiation as their energy source. To understand IR and NMR, therefore, you need to understand some of the properties of electromagnetic radiation— radiant energy having dual properties of both waves and particles. 

Spectroscopy is the study of the interaction between matter and electromagnetic radiation— radiant energy that displays the properties of both particles and waves. Several different spectrophotometric techniques are used to identify compounds. Each employs a different type of electromagnetic radiation. We will start here by looking at ultraviolet and visible (UVWis) spectroscopy. We will look at infrared (IR) spectroscopy in Chapter 13 and nuclear magnetic resonance (NMR) spectroscopy in Chapter 14. 

I luoreiiCence and phosphorescence are analytically important emission processes in which species arc ex-ciled hy absorption of a beam of electromagnetic radiation radiant emission then occurs as Ihe excited species return to the ground state. Fluorescence occurs more rapidly than phosphorescence and is cenerttlly complete after about 10 s from the time of excitation, Phosphorescence emission takes place over periods lunger than 10 s and may indeed continue for minulcs or even hours after irradiation has ceased. Fluorescence and phosphorescence arc most easily observed at a 90° angle to the excitation beam. 

All of the energy that drives the atmosphere is derived from a minor star in the universe—our sun. The planet that we inhabit, earth, is 150 million km from the sun. The energy received from the sun is radiant energy—electromagnetic radiation. The electromagnetic spectrum is shown in Fig. 17-1. Although this energy is, in part, furnished to the atmosphere, it is primarily received at the earth s surface and redistributed by several... 

Radiant temperature The temperature of a surface emitting heat to surrounding bodies by means of electromagnetic radiation. 

When you bake in the sun, your body absorbs energy from sunlight. Infrared radiation from a heat lamp in a restaurant keeps food warm until the server delivers the meal to the customer. When a microwave oven cooks food, the food absorbs energy from microwave radiation. Sunlight, infrared light, and microwaves are examples of electromagnetic radiation, which possesses radiant energy, as we discuss in Chapter 7. 

Radiant Energy—The energy of electromagnetic radiation, such as radio waves, visible light, x and gamma rays. 

Radiant energy Energy that is transmitted in the form of radiation, particularly electromagnetic radiation. 

Radiant energy (associated with electromagnetic radiation)... 

The situation becomes even worse when the Boltzmann formula is used to interpret the absorption of radiant energy by molecules. Electromagnetic radiation considered as a fluctuating electric field interacts with electrons in... 

The flame detector is an optical device that responds to the radiant energy that is given off by a flame. When a flame or explosion occurs within the field of view of the detector, the resulting electromagnetic radiation travels toward the detector at... 

The word radiant energy is the energy transmitted from one body to another in the form of radiations. This energy has wave nature and because it is associated with electric and magnetic fields, it is also called electro-magnetic radiations. The visible light, ultraviolet, infrared, X-rays, radio-waves and microwaves are all different forms of electromagnetic radiations. 

Solar energy is defined as the radiant energy transmitted by the Sun and intercepted by Earth. It is transmitted through space to Earth by electromagnetic radiation with wavelengths ranging between 0.20 and 15 pm. The availability of solar fiux for terrestrial applications varies with season, time of day, location, and collecting surface orientation. In this section, we shall treat these matters analytically (Kutz, 2007). 

A measure of the radiant power (P) for a parallel beam of electromagnetic radiation leaving or passing through... 

A dimensionless quantity, symbolized by t or T, equal to the transmitted radiant power, Ptr, divided by the radiant power incident on the sample, Po thus, t = Ptr/ Pq. It is a measure of the ability of a body, solution, entity, eta, to transmit electromagnetic radiation. It is synonymous with transmission factor. See also Internal Transmittance Transmission Density Total Transmittance Beer-Lambert Law Absorption Spectroscopy... 

All objects above absolute zero temperature (-273 °C) emit electromagnetic radiation in the IR region. Further, the emission of IR radiation is theoretically based on the concept of black body which is considered a perfect and efficient emitter. As the temperature of the object increases, wavelength of maximum emission shifts to the shorter wavelength region and therefore radiant energy is emitted in the IR and visible range. 

Although they appear quite different to our senses, visible light, infrared radiation, microwaves, radio waves, X rays, and other forms of radiant energy are all different kinds of electromagnetic radiation. Collectively, they make up the electromagnetic spectrum, shown in Figure 5.3. 

In the study of chemistry, the properties and composition of matter are investigated, along with the nature of electromagnetic radiation and how it affects matter. Electromagnetic radiation is radiant energy that exhibits wave properties and travels at the speed of light (when in a vacuum). 

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