Answer: When the reaction reaches equilibrium, the cell potential will be 0.00 V
Explanation:
Equilibrium state is the state when reactants and products are present but the concentrations does not change with time.
The equilibrium is dynamic in nature and the reactions are continuous in nature. Rate of forward reaction is equal to the rate of backward reaction.
The standard emf of a cell is related to Gibbs free energy by following relation:

The Gibbs free energy is related to equilibrium constant by following relation:

For equilibrium 
Thus 

Thus When the reaction reaches equilibrium, the cell potential will be 0.00 V
Answer: for an object or gas or liquid to float in another there must be a difference in density
Explanation:
Helium has a density of 0.18 kg/m³ and air has a density of 1.29 kg/m^³. If a balloon is filled with helium it will float in air due to density differences
Archimedes' principle states that the upward buoyant force that is exerted on a body immersed in a fluid, whether fully or partially submerged, is equal to the weight of the fluid that the body displaces
Answer:
Mass number (A) is the number of nucleons (proton and neutron) present in a atom.
Explanation:
electrons don't cout since they are thousandth's of the mass of protons or neutrons