The diagram represents osmosis taking place between two sucrose solutions of different concentrations.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2020). The mark or mark type is shown in brackets.

1. [1] water ;
2. [1] (E) sucrose ;
3. [1] (F) partially permeable membrane AW ;
4. [1] (G) water ;
5. [1] movement of solvent / water / G;
6. [1] water + from high to low water potential / G concentration OR water + from dilute to concentrated sucrose / E solution OR water + down its concentration gradient AW ;
7. [1] water / G + to left / from right ;
8. [1] through partially permeable membrane / F;
9. [1] sucrose / solute / E too large OR water / G small enough to pass through ;
10. [1] diffusion + water G;
11. [1] stops at equilibrium / concentration same on both sides AW ;