Answer:
C
Explanation:
They are stabil and full of valence electron.
Moving the electron away from the nucleus requires energy, so the electrons in the outer shell will have more energy than ones in the inner shell. Electrons always have a charge of -1, so the charge in the inner and outer shell will be the same. Therefore the answer is 3
Answer:
Explanation:
Electron affinity is the energy released in adding an electron to a neutral atom in the gas phase.
It is a measure of the readiness of an atom to gain an electron. This property is very peculiar to non-metals. The higher the value, the greater the tendency to accept electrons.
Across a period electron affinity increases due to the increasing nuclear charge not being compensated for.
Down a group, electron affinity decreases due to the low nuclear charge and the large atomic radii.
The exception to this rule is the stability of half-filled sublevels. For example, nitrogen has a configuration of 2,5 with sublevel notation of 1s²2s²2p³.
The p-sublevel has a degeneracy of three and the three electrons goes in singly. This makes the configuration stable.
We expect such an atom to have a higher electron affinity but its configuration is stable and carbon would have a higher affinity than it across the same period.
Half filled sublevels are exception to the trend of electron affinity.
Stannous flutoide is ionic
Answer:
Metallic bonding
Explanation:
Metals have low ionization energies. Therefore, their valence electrons are easily delocalized (attracted to the neighbouring metal atoms). These delocalized electrons are then not associated with a specific metal atom. Since the electrons are “free”, the metal atoms have become cations, and the electrons are free to move throughout the whole crystalline structure.
We say that a metal consists of an array of cations immersed in a sea of electrons
.
The electrons act as a “glue” holding the cations together.
Metallic bonds are the attractive forces between the metal cations and the sea of electrons.
In an NaK alloy, for example, the Na and K atoms contribute their valence electrons to the "sea". The atoms aren’t bonded to each other, but they are held in place by the metallic bonding.
