The
octet rule
What is a stable ion?
Atoms are at their
most stable when their outermost energy level is either empty of electrons or filled with electrons
. Ions. Sodium atoms have 11 electrons. Two of these are in the lowest energy level, eight are in the second energy level and then one electron is in the third energy level.
How do you determine if an atom is stable or unstable?
An atom is
stable if the forces among the particles that makeup the nucleus are balanced
. An atom is unstable (radioactive) if these forces are unbalanced; if the nucleus has an excess of internal energy. Instability of an atom's nucleus may result from an excess of either neutrons or protons.
How do you know if an element is stable?
An atom is stable
if the forces among the particles that makeup the nucleus are balanced
. An atom is unstable (radioactive) if these forces are unbalanced; if the nucleus has an excess of internal energy. Instability of an atom's nucleus may result from an excess of either neutrons or protons.
How do you know the charge of a stable ion?
When they lose electrons, they become positively charged and are named cations. When they gain electrons, they are negatively charged and are named anions. You can predict the charge of an ion by
looking at its group number on the periodic table
. Groups IA, IIA and IIIA all lose electrons and become positively charged.
What is the difference between a stable and unstable isotope?
Stable isotopes do not decay into other elements
. In contrast, radioactive isotopes
How does an atom's nucleus stay together and remain stable?
Inside the nucleus,
the attractive strong nuclear force between protons outweighs
the repulsive electromagnetic force and keeps the nucleus stable. Outside the nucleus, the electromagnetic force is stronger and protons repel each other.
What causes a nucleus to be unstable?
When the atoms of an element have extra neutrons or protons it creates extra energy in the nucleus
and causes the atom to become unbalanced or unstable. Whether radioactive elements
Why is iron so stable?
This stability is caused by
the attractive nuclear force between nucleons
. Iron 56 is the most stable nucleus. It is most efficiently bound and has the lowest average mass per nucleon. … It takes more energy per nucleon to take one of these nuclei completely apart than it takes for any other nucleus.
Are atoms more stable when combined?
Why Atoms Combine – Atoms want to be
stable
. A stable atom is a happy atom! – Compounds are more chemically stable than the elements from which they were made. … (8 electrons) – Energy levels are filled by elements gaining, losing, or sharing electrons.
Which ion has a charge of 2?
Explanation: Magnesium is under group 2 that also has a valence electron of 2. To achieve stability and to follow the octet rule, these 2 electrons in the outer shell will be removed making this atom into an ion with a 2+ charge.
What charge would each element obtain when it becomes an ion aluminum?
When an aluminum atom becomes an ion, it drops
three electrons
. Since there are only 10 electrons, their value is subtracted from the number of protons, and the difference is a positive three. Therefore, an ion of aluminum has a positive charge of three, shown as 3+.
What can you infer about an ion that has a positive charge?
Why does a neutral atom have no overall charge? … What can you infer about an ion that has a positive charge?
it has more protons than electrons
. What can infer about an ion that has a negitive charge?
What is the most unstable isotope?
Francium
is one of the most unstable of the naturally occurring elements: its longest-lived isotope, francium-223, has a half-life of only 22 minutes.
What causes isotopes to be unstable?
Usually, what makes an isotope unstable is the large nucleus.
If a nucleus becomes larger enough from the number of neutrons, since the neutron count is
what makes isotopes, it will be unstable and will try to ‘shed' its neutrons and/or protons in order to achieve stability.
Is oxygen stable or unstable?
One oxygen atom is unstable
since it has only 6 electrons in the outermost shell. For an atom to be stable it needs 8 electrons. So, for the oxygen atom to be stable it requires two more electrons in the valence shell.
