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
Boiling point, melting point, Appearance, mass, and taste.<span />
Answer:
hydrogen
Explanation:
it diffuses faster compared to helium since it is less dense
Answer:
The concentration of helium in the water is 2.405×10^-4 M
Explanation:
Concentration = Henry's law constant × partial pressure of helium
Henry's law constant = 3.7×10^-4 M/atm
Partial pressure of helium = 0.65 atm
Concentration = 3.7×10^-4 × 0.65 = 2.405×10^-4 M