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The atomic number is the number of protons in the nucleus of an atom. The number of protons in an atom's nucleus determines the chemical identity of that atom. It tells us which element it is. The elemental identity of an atom is determined by the number of protons in that atom's nucleus. This was bit repetitive, but it is a critical concept in chemistry and physics. Atomic Mass might be thought of as the "weight" of an atom. Atomic Mass is found by adding up the masses of all the protons, neutrons, and electrons in the atom. As electrons weigh less than 1/1800th of what a proton weighs, they contribute only the smallest amount to the weight of the atom (compared to the protons and neutrons), regardless of which atom it is. These weights are expressed in atomic mass units because the "normal" terms for the expression of weight (mass) are far too large to be "easy to work with" on the atomic scale. Let's do a quick example with the two stable isotopes of lithium. Lithium is element number three on the Periodic Table. It has 3 protons in its nucleus, and 3 is its atomic number. (Repeating, the number of protons in the nucleus is equal to the atomic number, and this identifies the element under investigation.) Lithium has one "version" or isotope that has 3 neutrons. The atomic mass of 3Li is about 6.015 or so. Note: subtracting the atomic number from the atomic mass gives us the number of neutrons in the nucleus of that atom. The 6.015 minus the 3 yields an answer of 3 for the number of neutrons. There is also a lithium atom that has 4 neutrons in its nucleus. It's 4Li and its atomic mass is about 7.016 or so. Same math. Take the 7.016 and subtract the 3 and get 4 as the answer - and the number of neutrons in the nucleus of that atom. Those are the two stable isotopes of lithium. (There are a number of other isotopes of lithium, but they're all unstable and disappear fairly quickly after being made in the physics lab.)
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What is the general relationship between atomic number and atomic mass weight?
As atomic number rises so does the atomic mass. There is no close relationship. Atomic number is the number of protons in the nucleus. Average atomic mass takes the mass of naturally occurrring isotopes which include the mass of the varying numbers of neutrons present which account for a large proportion of the overall mass of an atom.
What is atomic mass and the number of calcium?
Calcium has atomic number of 20, an atomic weight of 40.078 and an mass numbers of 40 - 48 inclusive in its isotopes. Atomic number is the count of protons in the nucleus. Mass number is the count of protons plus neutrons. The question refers to atomic mass rather than atomic weight. Atomic mass normally refers to the mass of a specific isotope of an element and is related to the mass number. Atomic weight ( or relative atomic mass as it is termed by IUPAC) the average mass of naturally occurring isotopes of an element. The relationship between mass number and atomic mass is defined in terms of the Atomic mass unit which is in simple terms 1/12 of the mass of a 12C atom. If you need to find out more about the relationship between mass number and and atomic mass you need to read the article "atomic mass unit" in wikipedia.
What is the relationship btw atomic mass and atomic mass number?
We can find atomic mass and mass number in chemical elements. Atomic mass is about weight of the atom. Mass number is about total of neutrons and protons.
What is the relationship between the atomic number and the atomic mass number?
Atomic number: number of protons in a nucleus unique to an element Atomic Mass number: number of protons + number of neutrons in a nucleus. May be a small range of values for a given element. Very roughly the atomic mass number is double the atomic number. For large elements it is more than double.
Is there any relationship between atomic mass and number of proteins and electrons?
Yes, there is a relationship between atomic mass and the number of protons and neutrons in an atom. The atomic mass is approximately equal to the sum of the number of protons and neutrons in an atom, as electrons have negligible mass compared to protons and neutrons. The number of electrons in a neutral atom is equal to the number of protons, in order to maintain a balanced charge.
Who found a relationship between the wavelengths of x-rays and the atomic number of elements?
Henry Moseley found the relationship between the wavelengths of x-rays and the atomic number of elements. He proposed that the atomic number of an element is better defined by the number of protons in the nucleus rather than by its atomic mass.
What is the difference between the atomic number mass number and atomic mass?
We can find Atomic Mass and mass number in chemical elements. Atomic mass is about weight of the atom. Mass number is about total of neutrons and protons.
What is Relation between atomic and mass numbers?
mass number=atomic number+no. of neutrons
What is the relationship between a atomic number and an atomic mass number?
Atomic number: number of protons in a nucleus unique to an element Atomic mass number: number of protons + number of neutrons in a nucleus. May be a small range of values for a given element. Very roughly the atomic mass number is double the atomic number. For large elements it is more than double.
What are the differences between atomic number and atomic mass?
Atomic mass is the mass of an atom in atomic mass units, and includes protons, neutrons, and electrons; and atomic number is the number of protons in the nucleus of the atom.
What is the difference between the atomic number and average atomic mass?
We can find Atomic Mass and mass number in chemical elements. Atomic mass is about weight of the atom. Mass number is about total of neutrons and protons.
What best describes the number of neutrons in an atom?
It is equal to the difference between atomic number and Atomic Mass number. A+
