Please help me with the formula . If an atom has 15 protons , how many electrons does it have? And how do I figure it out?
2006-09-08 06:35:59 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
atoms are usually neutral - which means they have no charge. So if an atom has 15 (positive) protons then it must have the same number of electrons (negative) to cancel the positive charge. Atoms also have neutrons which have no charge so don't worry about those.
An ionised atom such as Ca(2+) means that there are an excess of protons (i.e 2 more protons than electrons - which acounts for the +2). If it was K(-) then there is one more electron than there are protons
2006-09-08 06:39:56 · answer #1 · answered by Joe_Floggs 3 · 1⤊ 1⤋
If your element is neutral so number of electrons should be equal the number of protons so elemnt with 15 protons should have 15 electronsm, but if your element is an ion and that mean it will lose or gain electrons so that can be bit different ,,proton never change its number in all elements but electron can increase or decrease
Example
lithium Li has 3 protons and 3 elecrtons when its neutral
but can lose 1 electron when become an ion ( cation) and become with 3 protons and 2 electrons
2006-09-08 08:16:27 · answer #2 · answered by source_of_love_69 3 · 0⤊ 0⤋
There are hundreds of ways of presenting Periodic Tables. You can see some of them at www.chemlab.pc.maricopa.edu. The most familiar form is flat and rectangular with rows and columns, but this is only because this fits the pages of a book easily.
All modern Periodic Tables list the elements in order of increasing atomic number, often given the symbol Z. We know now that this is the number of protons in the nucleus of an atom and is sometimes called the proton number. However Dmitri Mendeleev, the Russian chemist who made the first Periodic Table in 1869, listed the elements known at that time in order of their relative atomic masses, Ar. This was for the simple reason that, at that time, the idea of atoms being made up of smaller sub-atomic particles, such as the proton, neutron and electron had not been developed.
Fortunately these two arrangements – in order of atomic number and of relative atomic mass - are almost identical. In the same way, you would probably get pretty much the same order if you listed all your classmates first in order of the width of their hands and then in order of the length of their feet.
2006-09-08 06:40:28 · answer #3 · answered by god knows and sees else Yahoo 6 · 0⤊ 1⤋
The neutral atom has the same number of electrons as protons. So the neutral atom has 15 electrons. However, it gains electrons to form anion.
2006-09-08 06:40:27 · answer #4 · answered by astrokid 4 · 1⤊ 1⤋
does the atom have a charge? If there is no charge than protons equal electrons p15, e15. If the atom has a charge of
-2 than it has two more electrons than protons p15, e17. If the atom has a charge of +4 than it has four more protons than electrons p15, e11.
2006-09-08 06:57:44 · answer #5 · answered by Alexis 4 · 0⤊ 0⤋
Ther is no such formula, apparently someone has put you on.
2006-09-08 06:38:41 · answer #6 · answered by x_squared 4 · 0⤊ 1⤋