The atomic number=5
The mass number=11
<h3>Further explanation</h3>
In the following element notation,

X = symbol of elemental atom
A = mass number
= number of protons + number of neutrons
Z = atomic number
= number of protons = number of electrons, on neutral elements
So for The atomic notation for a particular atom of Boron :
₅B¹¹
Z=5=atomic number
A=11=mass number
Where is the graph at? may you send a picture of it?
"For example; water is a covalent compound which is formed by the covalent bonding between hydrogen and oxygen atoms."
Chlorobenzene would essentially be a benzene ring that is substituted with chlorine. Thus it would have 6 carbon atoms, in its molecular formula.
The species bonds with the most ionic character is the compound with elements that develop the higher electronegativity difference between each other.
the most ionic character had maximum EN.
EN is max for SiO2
hope this help