The mass number is the combined number of protons and neutrons in the nucleus of the particular element you are looking at.
NOTE: (don't be confused by the Periodic Table) Different elements have isotopes with varying mass numbers, so the mass number displayed on a periodic table is the ratio of those isotopic mass numbers in any given sample of the element your examining. This ratio is often confused with with the mass number of the element when it is displayed on periodic tables, it is actually the relative Atomic Mass. You can tell if a number is the mass number or a relative atomic mass by whether or not it is a whole number if it is then it's a mass number if it has decimal places out beside it then you're looking at relative atomic mass.
mass number = number of protons + number of neutrons
The mass of a specific isotope.
Usually when saying "periodic," scientists usually refer to the periodic table. This table is the shortened version of gasses, solids, liquids, and so on.
The answer is Group 17 Halogens.
Sulfur is an element.Sulfur is an element, represented as S on the periodic table.
Hg is the symbol for MercuryIt comes from the Latin word hydrargyrum no its not its the symbol for hydrogen and it comes from the Irish word hydrargyrum
It means that 2 is calciums' mass number and atomic number
Ga on the periodic table means Gallium [MORE INFO...] Mass number is 70 Atomic number is 31 =p
could be either the atomic number or the mass number of the element, depending on what you are referring to.
Atomic weight, which is the mean relative mass and is dimensionless.
K on the periodic table is Potassium. It has a mass of 39.0983 amu and its atomic number is 19.K is the symbol for potassium.
do you mean the why is the average atomic mass not a whole number? because if that is your question, then the answer is that each element has multipal isotopes and the mass you see on the periodic table is the average of all the isotopes together. So there has to be a decimal on the periodic table of elements
Strictly, atomic mass is not organised on the periodic table - the periodic table is arranged according to the atomic number (i.e. the number of protons in the nucleus) of the elements.However, as the number of neutrons that are required in the nucleus increases as the number of protons increases, it means that with increasing atomic number you generally get a increase in atomic mass as you go further up the periodic table.BUT, there are exceptions - for complex reasons relating to nuclear stability, the average atomic mass of cobalt (atomic number 27) is actually greater than that of nickel (atomic number 28), and the atomic mass of plutonium (atomic number 94) is greater than that of Americium (atomic number 95).
Th is element number 90 on the periodic table It is thorium, it is in the Actinides, and it is radioactive
It is the Atomic Number.
Potassium, K, is in Group 1 of the periodic table
The number of period in periodic table.
The group number is an identifier used to describe the column of the standard Periodic Table in which the element appears.
It is number six in the Periodic Table.