Explanations:- A precipitation reaction is a double displacement reaction in which a solid salt is formed.
If we look at all the given equations then it's only second reaction in which a solid salt (CdS) is formed. In rest of the reactions there is no solid salt formed.
It means A, C and D are not the right choices and so the correct choice is only B.
Here the phase are given for all the products. If the phases are not given then we use the solubility chart to see which reactions would form the precipitate.
Since, the precipitate is formed only in second equation, the correct choice is B.
Movement of solute from a 0.2% solute concentration solution to a 0.4% solute concentration solution is an example of active transport.
-Active transport is the process by which dissolved molecules move across a cell membrane from a lower to a higher concentration. In active transport, particles move against the concentration gradient - and therefore require an input of energy from the cell.
-During active transport, a protein pump uses energy, in the form of ATP, to move molecules from an area of low concentration to an area of high concentration.