The number of protons in an atom determine what element it is, but atoms can have different numbers of neutrons to give it a different mass. When two atoms of the same element have different numbers of neutrons, they are called isotopes.
Most atoms have isotopes that occur naturally. An isotope is an atom with a different number of neutrons, but the same number of protons and electrons. Each element has a standard number of neutrons that can be found by looking at a periodic table.
The atomic weight of an element depends on the abundance of its isotopes.If you know the mass of the isotopes and the fractional abundance of the isotopes, you can calculate the element's atomic weight.
If you're given the mass of each isotope of an element, and the average atomic mass, you can calculate the percent (%) abundance of each isotope. Let "x" be one of the abundances, and the other ...
In this video we'll look at how to determine, calculate and solve for atomic number, mass number, isotopes, net charge, protons, neutrons, and electrons. We'll determine what element an atom is by ...
To calculate atomic mass, start by finding the atomic number of the element, which is the number above the element on the periodic table. Next, find the number of neutrons in the nucleus by subtracting the atomic number from the isotope number. Finally, add the atomic number and the number of neutrons to get the atomic mass.
Problem #6: Oxygen is composed of three isotopes: One has a a mass of 16.999 amu. This isotope makes up 0.037% of oxygen. Of the other two, one has a mass of 15.995 amu, and the other has a mass of 17.999 amu. Calculate the abundance of the other two isotopes, using the average atomic mass of 15.9994 amu. Solution:
The first isotope contains 143 (= 235 – 92) neutrons and the second 146 (=238 -92). The first isotope is used in atomic bombs and nuclear reactors. On the other hand, the second isotope does not have the properties necessary for these applications. There is another way to identify the isotopes of elements. Only the mass number is used
How to Find Average Atomic Mass. Average atomic mass is not a direct measurement of a single atom. Instead, it is the average mass per atom for a typical sample of a given element. If you could measure the mass of billions of individual...