Astudent wants to prepare a 1.0-liter solution of a specific molarity. the student determines that the mass of the solute needs to be 30. grams. what is the proper procedure to follow?
(1) add 30. g of solute to 1.0 l of solvent.
(2) add 30. g of solute to 970. ml of solvent to make 1.0 l of solution.
(3) add 1000. g of solvent to 30. g of solute.
(4) add enough solvent to 30. g of solute to make 1.0 l of solution.

The answer is (4) Add enough solvent to 30.0 g of solute to make 1.0 L solution. The molarity is calculated using volume of the solution. When solute dissolving, the total volume will change. So the final volume of solution need to be 1.0 L.

The  grandmother cell  is a hypothetical  neuronthat represents a complex but specific concept or object.[1]  it activates when a person "sees, hears, or otherwise sensibly discriminates"[2]  a specific entity, such as his or her grandmother. the term was in use at least as early as 1966 amongst staff and students in the department of experimental psychology, university of cambridge, england. a similar concept, that of the  gnostic neuron, was proposed two years later