0
Why don't elements in the periodic table have whole numbers for their atomic masses?
Wiki User
∙ 9y ago
If we look at hydrogen, we see it's the simplest of all the elements. It's basically one proton with an electron hanging around. Problem is, if we look at a whole bunch of hydrogen atoms, we find one every once in a great while that has a neutron hanging on to the proton in the nucleus. That atom of hydrogen has about twice the mass of a "regular" hydrogen atom. It's a distinct isotope of hydrogen. There are even some atoms of hydrogen that have two neutrons hanging on to that proton in the nucleus. The atoms of hydrogen with the neutrons are rare, but the difference in their masses and the fraction of the naturally occurring element that they make up must be accounted for.
As we go on up the Periodic Table to heaver elements, we find that pretty much all the elements have several isotopes that occur in nature, and some have significant portions distributed over two or more isotopes. Take Boron. It's atomic number is 5. How many neutrons are in a boron atom? Well, roughly 80% have 6 neutrons while about 20% have 5. When we weigh a sample of boron in the lab, we need to account for that.
If we look at tin, we find it has 10 naturally occurring isotopes! And we have to account for them all when we have a sample of tin because they are each in there in some amount. That's why the atomic masses of the elements aren't whole numbers. It would be simple if they did, but science demands we account for the variables in nuclear structure.
Wiki User
∙ 9y ago
Add your answer:
Earn +20 pts
A Russian chemist named Dmitri Mendeleev organized elements by?
Mostly by atomic mass, but in some cases by (educated) guess where he thought the measured atomic masses weren't correct.
Where do continental air masses form?
Continental air masses form in the United States
Why are protons and neutrons used in the subatomic particle?
Protons and neutrons provide the mass of an atom. Each different kind of element has a unique number of protons. For example: all hydrogen atoms have one proton. However, not all hydrogen atoms have the same mass. Some hydrogen atoms have no neutrons, one neutron, or two neutrons. Atoms of the same element (one proton) but different numbers of neutrons (different masses) are called isotopes of that element. All elements have isotopes. Some isotopes of elements are radioactive and are useful in medicine and energy applications (nuclear, for instance).
What are the land masses called that strat with a c?
Continents are land masses. Continent starts with the letter c.
What projection map shows size of various land masses?
The equal-area projection shows size of various land masses.
Why don27t elements in the periodic table have whole numbers for their atomic masses?
Because the masses of protons, neutrons and electrons are not whole numbers.
Why the atomic mass numbers listed for elements on the Periodic Table are not whole numbers.?
Why are atomic masses of elements not generally whole numbers? The atomic masses listed on the periodic table are a weighted AVERAGE of an element'sisotopes. ... An element's atomic number is the number of protons in its nucleus. Number of protons specifies atom type.
How are the atomic numbers and the atomic masses of the elements related to how the elements are arranged on peridoic table?
Elements are arranged in a periodic table by atomic number, lower on top and left. Atomic masses have no direct relationship to the arrangement of atoms, although generally atoms with higher atomic numbers will have higher atomic masses. (There are at least three exceptions for atoms with atomic numbers differing by 1.)
How did Mendeleev arrange chemical elements?
He arranged the elements in the increasing order of their atomic masses and repeating periodic properties.
Define periodic law?
Properties of elements are a periodic function of their atomic masses.
How do atomic numbers and atomic masses increase in the periodic table?
The atomic number and atomic masses increase as you move from left to right.
How are the elements in the first periodic table arranged?
In the first Periodic Table by Mendeleev, he arranged the elements in the increasing order of their atomic masses and repeating properties.
What is mendeleev's periodic law?
The physical and chemical properties of the elements are periodic functions of their atomic numbers.The periodic law states that the physical and chemical properties of elements are periodic functions of their atomic numbers. They influence the characters of an element more than atomic weight.
What is the basis of arranging the elements in the periodic table?
increasing atomic number and repeating properties
What does a periodic table have?
a modern periodic table should have the 118 elements, their atomic numbers, and their masses. to find the number of protons and electrons, they are the same as the atomic number. to find the neutrons, subtract the protons from the mass.
What is the periodic law?
Periodic Table of elements.
How were the elements arranged in the spiral periodic table?
in order of their reletive atomic masses
