Isotopes Flashcards

All 6 cards in this deck

What are isotopes?

Atoms of the same element with the same number of protons but different numbers of neutrons.

How do the atomic number and mass number compare for two isotopes of an element?

Same atomic number, different mass number.

How do you decide whether two nuclei are isotopes of the same element?
e.g. $^{12}_{6}\mathrm{C}$ and $^{14}_{6}\mathrm{C}$

1. Compare atomic numbers — they must be equal: both 6
2. Compare mass numbers — they must differ: 12 and 14
3. So they are isotopes of carbon (6 and 8 neutrons)

What gives the nucleus of an element its characteristic positive charge?

Its number of protons, which is the same for every atom of that element.

True or false? Isotopes of an element have nuclei with different positive charges.

False. The nuclear charge is the same; only the number of neutrons (and so the mass) differs.

True or false? Neutral atoms of two isotopes of the same element have the same number of electrons.

True. They have the same number of protons, so the same number of electrons.