This number is 40.
There are many isotopes that have a mass number of 40. Calcium 20 has a mass number of 40 but so does potassium 21 and Argon 22. Calcium twenty however is probably the one you want as it is more common then the other isotopes listed.
It is based on number of protons. Consider an element has 20 protons.Its atomic number is twenty.
It is element 29 on the periodic table. The elements in the periodic table are arranged according to increasing atomic number. The atomic number is the number of protons in the element's atoms.
If you're asking about a nickel atom, it depends on the isotope. In the case of the most common isotope, the answer would be 30. If you're asking about a nickel coin, I get about 1.625 x 1024. If this was for a homework problem, you'll probably want to carry out your own calculations or face embarrassing questions about how you arrived at that number. (It's also quite possible that I made a mistake.)
No Element Has that kind of Configuration
Calcium has twenty protons and twenty electrons. The main isotope of calcium also has twenty neutrons.
11 protons and 12 neutrons are there in Na-23.
It is calcium.
The atomic number is equal to the number of protons in the atom. Therefore, if an element has an atomic number of 24 (which in this case is chromium) then it has 24 protons. The mass number is the sum of the number of protons and neutrons.
''CA" (CAlCiUM)
Argon 38 has eighteen protons and twenty neutrons. Argon 36 has eighteen protons and eighteen neutrons.
Calcium is a metal element. atomic number of it is 20.
There are many isotopes that have a mass number of 40. Calcium 20 has a mass number of 40 but so does potassium 21 and Argon 22. Calcium twenty however is probably the one you want as it is more common then the other isotopes listed.
Calcium has twenty electrons in each atom.
An isotope atom of an element is one with the same number of protons in the nucleus (i.e the atomic number) but with a different number of neutrons giving it a different mass. Isotopes have the same chemistry because they have identical valence shells. An example is chlorine which is found in nature with two stable isotopes 35Cl with 18 neutrons and 37Cl with twenty. As 35 is around 75% and 37 25% in nature the atomic weight is 35.453.
26
It is based on number of protons. Consider an element has 20 protons.Its atomic number is twenty.