What is an isotope?

Question

i need to know this because i got a big chem test coming up and i have not payed attenion in chem =/

Answer 1

In an atom there are protons and neutrons in the neucleus, and electrons around it. The number of protons in the nucleus of the atom determines the atomic number and what element it is, however, there can be differing numbers of neutrons present. The number of neutrons determines which isotope it is and affects the atomic mass of the element, but it doesn't change the identity of the element. For example, carbon usualy has 6 protons and 6 neutrons with an atomic weight of 12, but some carbon has an extra neutron: (6 protons and 7 neutrons) it is still carbon, and behaves like carbon in reactions but it's atomic weight is 13. Some carbon has 2 extra neutrons (6 protons. 8 neutrons) and has an atomic weight of 14. Some of these isotopes are stable; some undergo radioactive decay.

Note: the mass of the electrons is so tiny compared to protons & neutrons, it usually can be ignored in these calculations.

Answer 2

Pay attention in class. That's the only way to pass a test. Unless you're naturally gifted of course. Then do whatever you want, except causing trouble.

An isotope is a varitaion of an element with the same numbers of protons and electrons, but a different amount of electrons. You might know it from radioactive isotopes. Read more at wikipedia. Look up "isotope"

Example: Carbon has 6 protons, neutrons, and electrons, thus making it Carbon-12. If we add one neutron, it becomes Carbon-13. DO NOT ADD PROTONS. If it does, it'll turn into Nitrogen-13 (assuming Carbon-12 sample.)

Answer 3

Isotopes are any of the several different forms of an element each having different atomic mass (mass number). Isotopes of an element have nuclei with the same number of protons (the same atomic number) but different numbers of neutrons. Therefore, isotopes have different mass numbers, which give the total number of nucleons—the number of protons plus neutrons.

Answer 4

Every atom of an element has the same number of protons and electrons, but they can have a different number of neutrons. Each different possible number of neutrons is an isotope.

Answer 5

The same element but different # of neutrons i.e.- uranium is 238/92 and 235/92, being as you were sleeping 238 and 235 are the number of protons plus neutrons, and 92 is the number of protons or neutrons. (they are always the same) the reason for uranium having two different isotopes is that the first in the example has three more neutrons than the second.

Answer 6

An isotope is one of several atomic forms of an element, each containing a different number of neutrons and thus differing in atomic mass.

Answer 7

Next time, maybe it would help to not doze off... or at least borrow a friend's notes.

Isotopes are several different forms of elements where each of their atomic masses are different.
In example, Carbon's normal atomic mass is about 12 g/mol.
However, an isotope of Carbon, Carbon-14's mass is 14 g/mol.

I hope this helps.

Answer 8

Any of two or more species of atoms of the same chemicalelement nearly identical in chemical behavior but differing in the number of neutrons. Greek isos, meaning equal + topos, meaning place.

Answer 9

isotope is the element itself with the same amount of protons, but the only thing that changed is the atomic number, which is called an isotope.

Answer 10

an isotipe is an atom has a diffrent number of neutrons but same # of protons remeber protns rule i'm in 8th grade and just did a chapter on this in science ask me if you have any other q& a's you think i can help with