Proton and neutrons are both present in the nucleus of the atom, they are also known as nucleons. While electrons are present in the energy levels.
2.1.2 State the relative masses of relative charges of protons, neutrons and electrons.
Protons have relative mass of 1 and relative charge of +1. It has a positive charge.
Neutrons have relative mass of 1 and relative charge of 0. It has no charge.
Electron have relative mass of 5 x 10^4 or 0.0005 and relative charge of -1. It has a negative charge.
2.1.3 Define the terms mass number (A), atomic number (Z), and isotopes of an element.
Mass number or relative atomic mass is how heavy an atom is compared to hydrogen. a.k.a (A)
Atomic number is the number of proton in an atom. a.k.a (Z)
Isotopes are the same element with the same number of proton but different number of neutrons.
Protium, Deuterium and Tritium are all isotopes of hydrogen. (Example)
2.1.4 Deduce the symbol for an isotope given its mass number and atomic number.
The symbol of an element is found by matching the "atomic number" with its corresponding one on the periodic table. It is important to use the atomic number because there are individual unique element for each atomic number.
2.1.5 Calculate the number of protons, neutrons and electrons in atoms and ions from mass number, atomic number and charge.
To calculate the number of neutrons, simply find A-Z. Since A is the number of both proton and neutrons, we can get the only neutron by subtracting the protons.
To calculate the number of electrons, simply find Z and its charge (n). Since protons should equal electrons in an atom, then the electron will be Z. However, if it is an ion then extra steps are required. If the charge is +1, then subtract one from Z and vice versa.
2.1.6 Compare the properties of the isotopes of an element.
Isotopes show the same chemical properties, as a difference in the number of neutrons makes no difference to how they react and so they occupy the same place in the Periodic Table.
The difference in mass lead to different physical properties such as boiling and melting points. Heavier isotopes move more slowly at a given temperature and these differences can be used to separate isotopes
2.1.7 Discuss the uses of radioisotopes.
Carbon 14 dating
Carbon 14 has eight neutrons which is too many to be stable. It can reduce the neutron to proton ratio when a neutron changes to a proton. This is beta radiation.
The relative abundance of carbon-14 present in living organism is constant due to breathing and carbon dioxide. However, when an organisms dies, it no longer absorbs carbon 14 and carbon 14 fall owing to nuclear decay. As this process occurs at a regular rate, we can determine the death of an organism to 5730 years.
Cobalt-60 Radiotherapy
Treatment of cancer and other diseases using ionizing radiation. The treatment damages the genetic material inside a cell and making it impossible to grow, though this damages both cancer cells and normal cells.
Iodine 131 Medical Tracer
Iodine 131 is an emitter of both beta and gamma rays can be used to investigate the activity of the thyroid gland and treat thyroid cancer It has a half-life of 8 days so it is quickly eliminated from the body.
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