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Lec: Isotopes and Ions. An Isotope is an element that has the same number of protons but a different number of neutrons. Example: C 12 ,C 13 , and C 14 have 6 protons but 6, 7, and 8 neutrons. The combination of the # of protons and neutrons equals the isotope #.
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An Isotope is an element that has the same number of protons but a different number of neutrons.
Example: C12,C13, and C14 have 6 protons but 6, 7, and 8 neutrons. The combination of the # of protons and neutrons equals the isotope #.
The nuclei of C12,C13, and C14 C14 C13 C12 Protons= Neutrons= C12 = 6 protons 6 neutrons C13 = 6 protons 7 neutrons C14 = 6 protons 8 neutrons
Determine what isotope is the atom below. Express you answer as an isotope number.
F19 9 Protons and 10 neutrons
Ion: An atom that has an electrical charge due to the increase or decrease of electrons.
All protons have a +1 electrical charge.All electrons have a -1 electrical charge.If an atoms protons and electrons are the same the atom is neutral.
An ion with a negative (-) electrical charge is an anion. • Examples of anions are expressed like this: • F- or C-2 • Fluorine (F) has gained an electron thus changing F to a (-1) electrical charge. Carbon (C) has gained two electrons thus changing the electrical charge to -2.
Example of an ion for F- Fluorine according to your PTE should have 9 electrons and protons however F- has 10 electrons and 9 protons.
An ion with a positive (+) electrical charge is an cation. Examples of cations are expressed like this: Li+ or C+2 Lithium (Li) has lost an electron thus changing Li to a (+1) electrical charge. Carbon (C) has lost two electrons thus changing the electrical charge to +2.
Example of cation for Li+ Lithium according to your PTE should have 3 electrons and protons however Li+ has 2 electrons and 3 protons.
Lec: Types of Radioactive Decay and Half-Life Alpha Particle Decay Beta Particle Decay Gamma ray
Alpha Particle Decay A positively charged helium (He+2) nuclei traveling at a high speed.
Beta Particle Decay A negatively charged electron particle that travels at a high speed.
The mass of an alpha particle is almost 8000 times more than a beta particle.
Gamma Ray An electromagnetic wave similar to X-rays. It can not be detected by your eyes. Gamma rays move at the speed of light.
Half-Life: The time it takes for a radioactive isotope total mass to decay by one half. A half-life can be anywhere from fractions of a second to millions of years. Example: U238 has a half-life over 4.5 billion years and Po214 is 0.0000016 second.
The half-life of Ra222 at the end of 0 half life. 100% still radioactive radon.
The half-life of Ra222 at the end of 1st half life. 50% still radioactive radon.
The half-life of Ra222 at the end of 2nd half life. 25% still radioactive radon.
The half-life of Ra222 at the end of 3rd half life. 12.5% still radioactive radon.
The half-life of Ra222 at the end of 4th half life. 6.25% is still radioactive radon.
Calculating the half-life of Ra222. Ra222 has a half-life of 4 days and starting mass of 800g.
Bismuth, Bi214 has a half-life of 20 minutes, how much will still be radioactive when it reaches its 4th half-life and when will this occur? The starting radioactive mass is 200g.
