You can acquire the atomic mass of any chemical element by using the periodic table. I've provided an example on a document below to help you identify the components of an element block from the periodic table. Now if you want to find the mass of an exact amount of a substance you use moles for that. That's why it's called molar mass. To find the molar mass of a substance follow this little guide:
*Use the third document I've inserted below to follow the guide.
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