Restate the question: it makes no sense; same element as what?
Two atoms are from the same element if they have the same number of protons in their nuclei. This is the defining characteristic that determines an element's identity. For example, all carbon atoms have 6 protons, so any two atoms with 6 protons are considered to be the same element, carbon.
No. Atoms of the same element can have different masses as the number of neutrons can vary. Atoms of the same element but with different masses are called isotopes.
The number of protons.
Element A and element B are the most likely to have similar properties because they belong in the same family, because if you know an element's family you can tell the number of valance electrons and the elements they react with. In periods, the properties are not alike, they slowly change in a pattern.
Same number of each kind of element to the left and right of the arrow.
No, isotopes of the same element are of different weight.
Atoms of the same element are alike in terms of their number of protons, which determines the element. However, atoms of the same element can differ in the number of neutrons they contain, leading to different isotopes of that element.
Because each isotope of an element has a mass different from any other isotope of the same element, and the atomic mass of an element is an average, weighted by the proportion of each isotope, in the naturally occurring element.
To a certain extent yes. In a balanced element the number of electrons match the number of protons in the core of the element. If electrons have been added or removed (as in an ion) then you would need to know the exact number added/removed, or rebalance the element, in order to determine the specific element.
Two nuclei contain the same element if they have the same number of protons in their atomic structure, which is defined by the atomic number. This number determines the element's identity, regardless of the number of neutrons or electrons. For example, both carbon-12 and carbon-14 are isotopes of carbon, as they both have six protons but differ in their neutron count. Thus, by comparing the atomic numbers of the nuclei, you can determine if they are the same element.
No. Atoms of the same element have the same chemical properties.
They may come from different isotopes of the same element, but not from the same atom.