The correct answer is option B. When the forward and reverse paths of a change occur at the same rate, <span>the system is in equilibrium specifically in dynamic equilibrium.</span> Dynamic equilibrium is
the balance in a process that is continuing. It is achieved in a reaction when
the forward rate of reaction and the backward rate of reaction is at the same
value or equal.
Difference in density between the two liquids
The average mass of an atom is calculated with the formula:
average mass = abundance of isotope (1) × mass of isotope (1) + abundance of isotope (2) × mass of isotope (2) + ... an so on
For the boron we have two isotopes, so the formula will become:
average mass of boron = abundance of isotope (1) × mass of isotope (1) + abundance of isotope (2) × mass of isotope (2)
We plug in the values:
10.81 = 0.1980 × 10.012938 + 0.8020 × mass of isotope (2)
10.81 = 1.98 + 0.8020 × mass of isotope (2)
10.81 - 1.98 = 0.8020 × mass of isotope (2)
8.83 = 0.8020 × mass of isotope (2)
mass of isotope (2) = 8.83 / 0.8020
mass of isotope (2) = 11.009975
mass of isotope (1) = 10.012938 (given by the question)
Metals are the most abundant
The basic units for density is

and any get of units that has those units in the proper place can be considered a density unit. The ones that has those specifically are A, B, E and F