Target: 10 questions in 10 minutes
1. Which of the following does not apply to solvation of solutes by water?
  • A. Water molecules interact with the positive and negative charges of the solute through hydrogen bonding or ion-dipole forces
  • B. Creation of a hydrolysis shell around each molecule of solute
  • C. Orientation of appropriate partially charged portion of the water molecule towards the solute
  • D. Solute polarity or charge plays an important role

Q2&3. The image shows two solutions separated by a semi-permeable membrane.

2 solutions seperated by semi-permeable membrane

 adapted from
H. Hoffmeister
public domain
2. In comparison to Y, region X can be described as:
  • A. Having lower water concentration
  • B. Hypertonic
  • C. Hypotonic
  • D. Having lower osmolarity 
3.  If a piece of plant tissue is placed in solution X, its mass will:
  • A. Increase
  • B. Decrease
  • C. Remain the same
  • D. Be indeterminate - cannot tell whether mass will change or not

Q4-6: A student cut some potato chips and placed them in different concentrations of sucrose solution. The chips were 50 mm long at the start. After 60 minutes she remeasured the chips and plotted a graph of her results:

graph to show effect of concentration of sucrose on potato chip size

potato chip section
4. In this investigation, which factor would not be a controlled variable?
  • A. Temperature
  • B. Potato surface area to volume ratio
  • C. Potato variety
  • D. Concentration of sucrose solution
5. Using the graph, at which sucrose concentration is a dynamic equilibrium reached?
  • A. 0.0%
  • B. 1.0%
  • C. 1.2%
  • D. 2.0%
6. Which of the following would not be an improvement of the investigation?
  • A. Carrying out repeats at each concentration
  • B. Adding error bars to the graph which show variability of repeats
  • C. Measuring both mass and length change
  • D. Increasing the intervals of sucrose concentrations studied

7. A similar experiment was repeated using red onion. The image below is a light micrograph of a sample of the red onion cells in 2.0% sucrose solution.

red_onion_cells

 Wikimedia
CC-BY-SA 3.0
Which description best matches cell X labelled in the image?
  • A. The cell becomes turgid due to net inflow of water
  • B. The cell becomes plasmolysed due to net outflow of water
  • C. The cell becomes flaccid due to a net outflow of water
  • D. The cell becomes soft due to net outflow of water

8. The image shows a light micrograph of red blood cells taken from a patient following an intravenous solution being given.

red_blood_cells

 Ed Uthman from Houston, TX, USA
CC-BY-SA 2.0
Which cell appearance would be compatible with the patient having been given a hypotonic solution intravenously?
  • A. I only
  • B.  II only
  • C.  I and II only
  • D. I and III only

Q9+10: The Image below shows a paramecium, a unicellular freshwater organism.

Paramecium organism

 Barfooz at the English Wikipedia.
CC-BY-SA 3.0
9. What structure is X?
  • A. Lysosome
  • B. Nucleus
  • C. Contractile vacuole
  • D. Mitochondrion
10. The paramecium is anaesthetised so that X can no longer function, then it is placed in distilled water. What is the likely outcome?
  • A. The paramecium will burst
  • B. The paramecium will become turgid
  • C. The paramecium will stay the same
  • D. Structure X will get smaller