In my last post I talked about my teaching tool, which helps students learn about the periodic table of elements with drawings of the atom, audio to explain, and LEDS and beeps to show the valence electrons. However, no study of the periodic table is complete without learning about RADIOACTIVITY. That is why I decided that it would be a great addition to my project. Here is a study of why it is important to learn about radioactivity, followed by an extension to my tool above showing the Geiger Counter Simulation, and a new tool and a tactile model that teaches about the different types of radiation.
It is very important to know about the radioactivity that helps us in so many ways!
First I extended my periodic table tool, so that for the radioactive elements, it says and prints on the screen that they are radioactive.
Further, I researched and found that there are 5 levels of radioactivity: very low (1), low (2), medium (3), high (4), very high (5). So besides telling it is a radioactive element, it also tells which level of radioactivity the element belongs to.
The Geiger counter is an instrument used to measure the level of radioactivity. It is a meter that shows how much radiation there is and sometimes it also comes with beeps.
I simulated this, so that there is a dial and it moves to the indicated level of radioactivity, and also beeps as many times as the level is. So for a very high radioactive element, it would beep 5 times. Braille stickers are added to the dial, so the visually impaired can touch and feel, which level the needle, is pointing to. They can also hear and count the beeps, and hear the tool tell about it.
Besides the above, I made a new teaching tool and a physical model that teaches and explains about the different types of radiation for someone who is eager to learn more!
An Alpha particle is made up of two protons and two neutrons. Once released, the particle will not travel very far in air. This is because, in just a few centimeters, it accumulates electrons, turning into a Helium atom within seconds. In fact, most of the Helium in the atmosphere comes from Alpha Radiation! Alpha particles are very massive, making it very hard for them to penetrate through any surface. External exposure to alpha radiation poses no danger–even human skin can stop them without getting damaged! However, ingesting or inhaling them, leads to almost certain death. As, due to their massive size, they cause disruptive damage to cells leading to the failure of major organs. This radiation takes place when an atom has too many protons and neutrons and it is in a hyperactive, unbalanced state. As a result of Alpha Radiation, the atomic number of an atom will go down by two and the mass number will decrease by four, lending more stability to the nucleus. To the right is a picture from my tool, explaining this radiation. It talks as it draws, to aid the visually impaired to understand.
A Beta Minus particle consists of one electron. While the Beta Minus particle is MUCH smaller than an Alpha particle, it penetrates farther than an alpha particle, but not too much, as being just an electron, it gets attached to some other atom there by ionizing it. It can easily pass through skin (unlike the Alpha particle), but can be stopped by a thin sheet of aluminum. Normally, Beta Radiation takes place when an atom has too many neutrons in comparison to protons, resulting in a high-energy, unbalanced nucleus. The atomic number increases by one and the mass number stays the same. My tool draws as it voices showing this (see video).
Gamma Radiation is waves of energy. Gamma waves are given off when an atom is in a highly energized state and needs to let out some energy. It is the product of radioactive atoms. Its wave length is less than one-tenth of a nanometer, making it the most energetic wave of the electromagnetic wave spectrum. Emitting Gamma Radiation makes no difference to the radioactive atom other than making it more stable (by reducing excess energy), but it will ionize other atoms by ripping away their electrons (due to the excess energy). It penetrates the most! My tool shows this (see right):
In this model, the giant Alpha particle is being stopped by someone’s hand (skin). The much smaller Beta particles are being blocked by a thin sheet of Aluminum. Finally, the Gamma rays are piercing into a thick block of Lead, only being stopped halfway through the block. This model shows how strong each type of radiation is. This is a special tactile model built so the visually impaired can also feel the model and understand what it is showing.
The Beta Plus/Positron particle is made up of a positron (a positive electron). This radiation takes place when the atom has too many protons and is super energetic. A proton becomes a neutron, releasing a neutrino and a positron. This decreases the atomic number by one, but makes no difference to the mass number. This radiation, however, is very weak. This is because, as soon as it is released, the positron will immediately meet an electron and cancel itself out into nothingness (since positrons and electrons are opposites). That’s why this radiation doesn’t travel very far.
In Electron Capture Radiation, a proton captures a first-orbit electron and becomes a neutron, releasing a neutrino. Then, an outer orbit electron fills the inner orbit hole, emitting X-Rays and (if the nucleus is still in a high-energy, excited state) Gamma Rays. This takes place when an atom has too many protons, but not enough neutrons (since you are losing a proton and gaining a neutron). It will decrease the atomic number by one and make no difference to the mass number. In addition, the Gamma Rays and X-Rays will ionize other atoms.
By Hari Bhimaraju
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