Add 200 mL of water to the measuring cup.
Place a paper towel on the scale and measure out 45 g of magnesium sulfate-7H2O.
Dissolve the 45 g of magnesium sulfate-7H2O in the water with one of the plastic spoons.
Pour 75 mL of the magnesium sulfate solution into each of the two small bowls. Use your graduated cylinder for precise measurements.
Cut a square of paper towel about 7 cm on a side.
Place a single paper towel in both solutions, so that it forms a "salt bridge" between them.
The salt bridge should be soaked with the solution. If there is a dry spot, add some magnesium sulfate solution to wet it.
It is not critical how the paper towel is placed in the solutions, as long as it makes good contact with both solutions.
Add a few drops of the universal pH indicator to each bowl. This will give you visual cues about the pH of the solution.
Use the pH meter to check the starting pH of the magnesium sulfate solutions.
Use the instructions that came with the instrument.
It is a good idea to calibrate the pH meter. If standard solutions came with your pH meter, use them as explained in the instrument's instructions.
Record the time and the pH in your lab notebook.