Answer:
Taking into account the definition of average atomic mass and isotopes of an element, the information that you need is the masses of its isotopes and their percent abundances.
Each chemical element is characterized by the number of protons in its nucleus, which is called the atomic number Z.
But in the nucleus of each element it is also possible to find neutrons, whose number can vary. The atomic mass (A) is obtained by adding the number of protons and neutrons in a given nucleus.
The same chemical element can be made up of different atoms, that is, their atomic numbers are the same, but the number of neutrons is different. These atoms are called isotopes of the element.
The atomic mass of an element is the weighted average mass of its natural isotopes. Therefore, the atomic mass of an element is not a whole number.
The weighted average means that not all isotopes have the same percentage.
In other words, the atomic masses of chemical elements are usually calculated as the weighted average of the masses of the different isotopes of each element, taking into account the relative abundance of each of them.
Explanation:
If you have to write the chemical formula of a simple, binary ionic compound given the name of the compound, you follow a set of three steps. Let's go through them using magnesium chloride as an example. Write the symbols for the cation and the anion: Mg and Cl. Determine the charge on the cation and anion.
The answer is (4) synthesis. Synthesis reaction means that two or more reactants combine directly to one production. Substitution or single replacement means that one element of a compound is replaced by another element. Double replacement means that two ionic reactants exchange ions to form two new productions.
Mass of molecule (g) = Mr of substance over avarogado constant