#"Atom W has 9 protons and 9 neutrons, Atom X has 8 protons and 9"# #"neutrons. Atom Y has 9 protons, and 9 neutrons. Atom Z has 10 protons"# #"and 10 neutrons."# What are the isotopes?

1 Answer
anor277
Mar 14, 2017

The number of nuclear protons gives #Z#, the atomic number......

Explanation:

And #Z# defines the identity of the element: #Z=1,H;Z=2,He;..........Z=6,C;........Z=37, Ru...........#

You don't have to remember these numbers, because a Periodic Table will be supplied to you in every test of chemistry and physics. You do have to be able to USE the Table.

Nuclear protons are conceived to have a positive charge. For a NEUTRAL element, there thus must be an equal number of negative charges, and these are supplied by #"electrons"#, which have negligible mass, unlike the proton, and are conceived to whizz about the nuclear core.

Also contained in the nuclear core, are various numbers of neutrons. Because a particular element may have various numbers of neutrons, this gives rise to the existence of #"isotopes"#, which are the same element, but isotopes have slightly different mass.

And so we identify the given nuclides, armed with a Periodic Table. All I do is look up the number #Z#, given by the number of protons:

#"Atom W"# #=# #"9 protons and 9 neutrons"#, #""^18F#

#"Atom X"# #=# #"8 protons and 9 neutrons"#, #""^17O#

#"Atom Y"# #=# #"9 protons and 9 neutrons"#, #""^18F#

(i.e. #W# and #Y# are the same isotopes)

#"Atom Z"# #=# #"9 protons and 10 neutrons"#, #""^19F#

#Z# and #Y# are different isotopes of the fluorine element. #W# and #Y# are the SAME isotope.

Please don't be blinded by science, and a few unfamiliar terms. The concept is fairly simple, and if you persist you will master it. A final question. We have #Z=92# for an unknown element. It has #146# neutrons in its nucleus. Can you identify the element, and the relevant isotope?

Related questions
See all questions in Isotopes
Impact of this question
12935 views around the world
You can reuse this answer
Creative Commons License