Answer:
The equilibrium shifts to the left, and the concentration of Ba2+(aq) decreases
Explanation:
Whenever a solution of an ionic substance comes into contact with another ionic compound with which it shares a common ion, the solubility of the ionic substance in solution decreases significantly.
In this case, both BaSO4 and Na2SO4 both possess the SO4^2- anion. Hence SO4^2- anion is the common ion. Given the equilibrium;
BaSO4(s) <—> Ba2+ (aq) + SO4 2- (aq), addition of Na2SO4 will decrease the solubility of BaSO4 due to the presence of a common SO4^2- anion compared to pure water.
This implies that the equilibrium will shift to the left, (more undissoctiated BaSO4) hence decreasing the Ba^2+(aq) concentration.
Sugar is made of molecules that are bonded together based on the positively and negatively charged areas. They will slowly dissolve in water. Pebbles are solids. They will sit in water for a long time. Though shale pebbles will break apart or fall apart.
Hope this helps. I provided step by step in the picture below if you want to see how I got these answers.
A= 1.0L
B= 0.50atm
C= 0.60atm
D= 4.0L