how to do calculations of
protons electrons and neutrons
Answers
Answer:
Explanation:
1
Get a periodic table of elements. The periodic table is a chart that organizes elements by their atomic structure. It is color-coded and assigns each element a unique 1 or 2-letter abbreviation. Other elemental information includes atomic weight and atomic number.[1]
You can find a periodic table online or in a chemistry book.
In tests, normally, a periodic table will be provided.
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2
Find your element on the periodic table. The table orders elements by atomic number and separates them into three main groups: metals, non-metals, and metalloids (semi-metals). Further elemental groupings include alkali metals, halogens, and noble gases.[2]
Using the group (columns) or period (rows) can make the element easier to locate on the table.
You can also search the table for the symbol of the element if you don’t know any other properties.
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3
Locate the element’s atomic number. The atomic number is located above the element symbol, in the upper left-hand corner of the square. The atomic number will tell you how many protons make up a single atom of an element.[3]
For example, boron (B) has an atomic number of 5, therefore it has 5 protons.
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4
Determine the number of electrons. Protons are particles in the nucleus of an atom that have a positive charge equal to +1. Electrons are particles that have a negative charge equal to -1. Therefore, an element in a neutral state will have the same number of protons and electrons.
For example, boron (B) has an atomic number of 5, therefore it has 5 protons and 5 electrons.
However, if the element includes a negative or positive ion, then the protons and electrons will not be the same. You will have to calculate them. The ion number will appear as a small superscript after the element.
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5
Look for the atomic mass of the element. To find the number of neutrons, you will first need to find the atomic mass. An element’s atomic mass (also known as the atomic weight) is the weighted average mass of atoms of an element.[4] The atomic mass can be found underneath the symbol for the element.
Make sure that you round the atomic mass to the nearest whole number. For example, the atomic mass of boron is 10.811, but you can just round the atomic mass up to 11.
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6
Subtract the atomic number from the atomic mass. To find the number of neutrons, you will need to subtract the atomic number from the atomic mass. Remember that the atomic number is the same as the number of protons, which you have already identified.[5]
For our boron example, 11 (atomic mass) – 5 (atomic number) = 6 neutrons
Mass number = protons + neutrons