Where is the atomic mass in the periodic table of elements?

Answer 1

It is USUALLY on the top right corner of the box.

Example: Hydrogen

1 1.01

H

The bold #(1.01) is the elements Atomic Mass.

*the atomic mass may vary because some books round to a certain place.

Answer 2

On the Periodic Table each element will have 2 numbers. One will be a whole number going from 1 hydrogen to 113 or so. This is the atomic number which is the number of protons it has. There will also be a number with a few decimal places. Carbon has a atomic number of 6 (as it is element number 6 and has 6 protons.) and an atomic mass of 12.011. The atomic mass is the average mass of a an atom for Carbon 99% of the atoms have a mass 12 (6 protons and 6 neutrons) and 1% has a mass of 13 the average of the two (0.99 X 12) + (0.01 X 13) = 12.011

Answer 3

The average atomic mass is generally, the number in the top right corner of an element's box. However, this may differ depending on the table. A general rule of thumb for deciphering the location of the atomic mass is looking for numbers that gradually increases from left to right.

Hope that helps :)

Answer 4

The atomic and mass numbers are usually found in small print above or below the element symbol with the atomic number usually being the number that increases by 1 across the table.

Answer 5

In an expanded periodic table, the "atomic number" (element number) is the number located in the upper left corner and the "atomic weight" is the number located in the bottom left corner.