no you do not need to know the atomic number, as that only equates to the number of protons in an atom. Most periodic charts will show you the atomic mass of an element
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.
To calculate the atomic mass of an atom, you would need to know the atomic number (number of protons) and the mass number (sum of protons and neutrons) of the atom. The atomic mass is typically a weighted average of the isotopes of that element based on their abundance.
To find the atomic notation for an atom, you need to know the number of protons, neutrons, and electrons in the atom. The atomic notation includes the element symbol, atomic number, and mass number. The atomic number is equal to the number of protons in the atom, and the mass number is the total number of protons and neutrons in the atom.
The mass number of an isotope is the number of neutrons and protons in the isotope, let this be p +n = (mass number). To find the number of neutrons you need the atomic number (number of protons), let this be p. You then subtract the two: mass number - atomic number = no. of neutrons p + n - p = no. of neutrons = n
12 neutrons has nothing to do with atomic number. Atomic number is the number of protons. You might mean sodium. Sodium has an atomic number of 11, and an atomic mass that rounds to 23, so 23 -11 = 12 neutrons in some isotopes of sodium. but some atoms of magnesium atomic number 12 also have 12 neutrons with a mass number of 24, and probably some other element, but those are all I can think of now.
You need to find the atomic number, and the atomic mass. The atomic number i the number of PROTONS in the nucleus, the atomic mass, or mass number, is the number of PROTONS and NEUTRONS in the nucleus. To find the number of neutrons you subtract the atomic number from the mass number.
atomic number and its squrare
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.
Mass number is the sum of protons and neutrons in the nucleus of the atoms of a particular isotope. The atomic number is the number of protons, so you would also need to know the number of neutrons. You could not determine the mass number from the atomic number alone.
To calculate the atomic mass of an atom, you would need to know the atomic number (number of protons) and the mass number (sum of protons and neutrons) of the atom. The atomic mass is typically a weighted average of the isotopes of that element based on their abundance.
To find the atomic notation for an atom, you need to know the number of protons, neutrons, and electrons in the atom. The atomic notation includes the element symbol, atomic number, and mass number. The atomic number is equal to the number of protons in the atom, and the mass number is the total number of protons and neutrons in the atom.
Look on a periodic table. If you have different isotopes then you need to multiply the mass number and atomic number and then find the average of them and you'll have the average atomic mass which is the same as on the periodic table. The location of the mass number on a periodic table depends but it's normally the one with a decimal.
i need help
The mass number of an isotope is the number of neutrons and protons in the isotope, let this be p +n = (mass number). To find the number of neutrons you need the atomic number (number of protons), let this be p. You then subtract the two: mass number - atomic number = no. of neutrons p + n - p = no. of neutrons = n
The atomic number is the number of protons and therefore, assuming the atom is neutral, the number of electrons. You would need to additionally know the atomic mass to figure out the number of neutrons.
12 neutrons has nothing to do with atomic number. Atomic number is the number of protons. You might mean sodium. Sodium has an atomic number of 11, and an atomic mass that rounds to 23, so 23 -11 = 12 neutrons in some isotopes of sodium. but some atoms of magnesium atomic number 12 also have 12 neutrons with a mass number of 24, and probably some other element, but those are all I can think of now.
1. Locate the element on the periodic table.2. Find the element’s atomic number (which is the same as the number of protons)3. Find the element’s atomic weight.4. Round off the atomic weight to the nearest whole number to find the atomic mass.5. Subtract the atomic number from the atomic mass (The numbers after the decimal point represent the usually very small mass of the electrons in the atom.)