Components of an atom

After Chadwick s discovery, scientists knew the three components of an atom protons and neutrons in the nucleus with electrons hovering outside. The masses and charges of these constituents are shown in Table 3.1. Chemists have developed a system to describe the elements based on their atomic makeup. The atomic number of an atom is the number of protons in the nucleus. This number is usually represented by the letter Z. Thus, for hydrogen Z = 1, for helium Z = 2, and so on. 

Figure 1 The essential components of an atomic absorption spectrometer (not drawn to scale)...

It turns out that the mass of an individual atom is always less than the sum of its parts. That is, if you add up the masses of all the components of an atom, you will not get the total mass of the atom. As an example, let s look at oxygen-16. 

The sum of the masses of the individual components of an atom is greater than the actual mass of the atom. This is due to the mass that is converted into energy as the nucleons bind together. 

All matter is composed of the same building blocks called atoms. There are two main components of an atom. 

The components of an atomic absorption spectrometer are a radiation souree, an atomization cell, a sample introduction system, a method of wavelength selection and a detector (Fig. 27.2). 

The main components of an atomic emission spectrometer are an atomization and ionization cell, a method of sample introduction, the spectrometer and detector. In contrast to AAS, no radiation source is required. 

Figure 3-12 Basic components of an atomic absorption spectrophotometer.

In relativistic theory a wave function has four components, two large components and two small components. For simplicity, we consider only the two large components of an atomic p orbital. Due to spin-orbit coupling brought about by the relativistic effect, the p orbitals of an atom are given by the atomic pi/2 and P3/2 orbitals [24-26]... 

Figure 2.45 Schematic diagram of a single-beam flame atomic absorption spectrometer (While the components of an atomic fluorescence spectrometer are similar, the emitted radiation is monitored perpendicular to the incident radiation).

Thus, keep in mind the starting definitions of Chapter 1. The Slater function approximation to the radial component of an atomic orbital is defined by... 

Radiometric dating is a method that scientists use to measure the age of things. The most widely known form of radiometric dating is that based on carbon-14. It works like this. Carbon-12 is the most common form of carbon, and carbon-14 is what is called an isotope of it. (An isotope is a variation of the normal atom of an element, in that it has more or less neutrons than the standard atom.) Carbon-12 has six protons and six neutrons at its nucleus, and is therefore said to have an atomic weight of 12. The component of an atom that determines its character is the number of electrons in orbit around its nucleus. In carbon s case there are six. 

The instrumental requirements of atomic absorption spectrometry will be discussed in the following section. In Fig. 12.3, the essential components of an atomic absorption spectrometer are depicted schematically a suitable radiation source, an... 

The two Zeeman components of an atomic level (L = 1, 5 = 1/2, / = 1/2) are coherently excited by a short laser pulse. Calculate the quantum-beat period of the... 

Components of an atom. The nucleus is made up of protons and neutrons. Electrons orbit the nucleus like tiny planets. 

Figure 6 Schematic representation of the essential components of an atomic force microscope.

Scanning Probe Microscopy, Figure 5 The basic components of an Atomic Force Microscope showing the stationary sample configuration with the tip mounted on the scanning tube... 

---