Question

A cell is 90% water outside and 14% salt inside. What is the direction of osmosis?

Answer 1

Into the cell.

Explanation:

Osmosis is the movement of a solvent from a high solvent concentration to a low solvent concentration across a semi-permeable membrane. If we have a 14% salt solution inside the cell, we assume that the rest, 86%, is water (in this question at least, since we're only dealing with salt and water). The solvent in this case is water, and the solute is salt.

Comparing the concentration of solvent on both sides, we see that there is a higher concentration of solvent outside the cell than inside (90% vs 86%). As the concentration of solvent is higher outside, the direction of osmosis will be inwards as to relieve the concentration gradient and reach equilibrium.

Osmosis and diffusion bot fulfill this criteria.