<span>If you give it a good search, the most used answer would probably be as follows,
</span><span>In 1914 Henry Moseley found a relationship between an element's X-ray wavelength and its atomic number (Z), and therefore rearranged the table by nuclear charge / atomic number rather than atomic weight. Before this discovery, atomic numbers were just sequential numbers based on an element's atomic weight. Moseley's discovery showed that atomic numbers had an experimentally measurable basis.
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Hope this helps!
In general chemistry, isotopes are a group of substances that belong to the same element. An element is characterized in the periodic table by their atomic number, which is the number of protons in an atom. Therefore, these substances have the same atomic numbers, but differ in mass numbers. Mass number is the sum of the number of protons and neutrons in the nucleus of an atom.
To determine the atomic weight of an element, you take the average weight of all the existent isotopes of that said element. The calculation would require to multiply the exact mass of the isotope to its abundance. Then, sum them all up.
Atomic weight = 98(0.18) + 112(0.82)
Atomic weight = 109.48 amu
C) the scientist made an identification by identifying the amount of drug in her blood and realising it was high
Actions form positive ions while anions forms negative
Explanation:
Characteristic of matter that is not associated with its change in chemical composition.