The Atom and Electromagnetic Radiation

You are watching: Total number of electrons in carbon

Fundamental Subatomic Particles Electromagnetic Radiation
Light and Other develops of Electromagnetic Radiation

Particle Symbol Charge Mass
electron e- -1 0.0005486 amu
proton p+ +1 1.007276 amu
neutron no 0 1.008665 amu

The variety of protons, neutrons, and electrons in one atom can be identified from a collection of basic rules.

The variety of protons in the cell nucleus of the atom is equal to the atom number (Z). The variety of electrons in a neutral atom is equal to the number of protons. The mass number of the atom (M) is same to the amount of the variety of protons and neutrons in the nucleus. The variety of neutrons is same to the difference in between the mass variety of the atom (M) and also the atomic number (Z).

Examples: Let"s identify the variety of protons, neutrons, and also electrons in the adhering to isotopes.

12C 13C 14C 14N

The different isotopes the an facet are figured out by creating the mass variety of the atom in the top left edge of the symbol for the element. 12C, 13C, and 14C are isotopes that carbon (Z = 6) and also therefore contain six protons. If the atoms space neutral, they also must contain six electrons. The just difference between these isotopes is the number of neutrons in the nucleus.

12C: 6 electrons, 6 protons, and also 6 neutrons

13C: 6 electrons, 6 protons, and also 7 neutrons

14C: 6 electrons, 6 protons, and 8 neutrons

Practice trouble 1:

Calculate the number of electrons in the Cl- and Fe3+ ions.

Click here to examine your answer to Practice difficulty 1

Electromagnetic Radiation

Much of what is known around the framework of the electron in an atom has actually been obtained by examining the interaction in between matter and different develops of electromagnetic radiation. Electromagnetic radiation has some of the nature of both a particle and also a wave.

Particles have actually a identify mass and also they accounting space. Waves have no mass and yet they bring energy as they travel through space. In enhancement to their ability to carry energy, waves have four other characteristic properties: speed, frequency, wavelength, and also amplitude. The frequency (v) is the variety of waves (or cycles) every unit the time. The frequency the a tide is reported in units of cycles per 2nd (s-1) or hertz (Hz).

The idealized illustration of a tide in the figure below illustrates the meanings of amplitude and also wavelength. The wavelength (l) is the smallest distance in between repeating clues on the wave. The amplitude that the tide is the distance between the greatest (or lowest) suggest on the wave and also the facility of heaviness of the wave.


If we measure the frequency (v) that a wave in cycles per 2nd and the wavelength (l) in meters, the product of these two numbers has the units of meters every second. The product the the frequency (v) time the wavelength (l) the a tide is as such the speed (s) in ~ which the wave travels with space.

vl = s

Practice trouble 2:

What is the speed of a tide that has actually a wavelength of 1 meter and also a frequency the 60 cycles every second?

Click below to inspect your answer to Practice problem 2

Practice trouble 3:

Orchestras in the United claims tune their instruments to one "A" that has actually a frequency that 440 cycles per second, or 440 Hz. If the speed of sound is 1116 feet per second, what is the wavelength that this note?

Click right here to check your answer come Practice difficulty 3

Click right here to see a solution to Practice difficulty 3

See more: Here"S Where The Microsd Slot Will Be On The Motorola Droid Mini Sd Card Slot

Light and Other creates of Electromagnetic Radiation

Light is a wave v both electric and also magnetic components. It is therefore a form of electromagnetic radiation.

Visible light consists of the narrow band the frequencies and also wavelengths in the part of the electro-magnetic spectrum the our eyes can detect. It includes radiation with wavelengths between about 400 nm (violet) and also 700 nm (red). Due to the fact that it is a wave, light is bent once it enters a glass prism. As soon as white light is concentrated on a prism, the light rays of various wavelengths room bent by differing quantities and the irradiate is transformed into a spectrum the colors. Starting from the side of the spectrum where the irradiate is bending by the smallest angle, the colors room red, orange, yellow, green, blue, and violet.

As we deserve to see indigenous the adhering to diagram, the energy carried by light rises as we go indigenous red come blue throughout the visible spectrum.


Because the wavelength the electromagnetic radiation have the right to be as long as 40 m or as brief as 10-5 nm, the visible spectrum is only a small section of the total range of electromagnetic radiation.


The electromagnetic spectrum contains radio and also TV waves, microwaves, infrared, visible light, ultraviolet, x-rays, g-rays, and also cosmic rays, as presented in the figure above. These various forms that radiation all travel at the rate of irradiate (c). Lock differ, however, in your frequencies and wavelengths. The product of the frequency time the wavelength of electromagnetic radiation is always equal come the speed of light.

vl = c

As a result, electromagnetic radiation that has a long wavelength has actually a short frequency, and also radiation with a high frequency has actually a short wavelength.

Practice trouble 4:

Calculate the frequency the red irradiate that has a wavelength of 700.0 nm if the speed of light is 2.998 x 108 m/s.