The most common method for this lab is the , which relies on the balance of gravity and surface tension forces at the moment a drop breaks away from a tube. Objective: Determine the surface tension of water. Formula: = mass of one drop. = acceleration due to gravity ( = internal diameter of the pipette or tube. 📝 Step-by-Step Execution 1. Gather Equipment

Soap is a surfactant (PAV) that significantly the surface tension of water. Why do drops form spheres?

Surface tension as temperature increases because molecules move faster and weaken intermolecular bonds. What if you add soap?

Surface tension forces act to minimize the surface area for a given volume, and a sphere has the smallest surface area. ⚠️ Common Errors to Avoid

. For pure water at room temperature, your result should be close to the reference value of . 💡 Typical "Check Your Knowledge" Answers

You will need a pipette or medicine dropper, a beaker of water, a small empty beaker for collecting drops, sensitive scales (electronic or balance), and a caliper (shtangentsirkul) to measure the tube diameter. 2. Measure the Diameter Use the caliper to measure the inner diameter of the dropper tip. Convert this value to meters ( 3. Collect Data Weigh the empty beaker ( M1cap M sub 1 Carefully count exactly drops (e.g., 50 or 100 drops) into the beaker. Weigh the beaker with the water ( M2cap M sub 2 Calculate the total mass of the water: Calculate the mass of a single drop: 4. Calculate Plug your values into the formula: