The surface tension of water at room temperature around 20C or 68F is approximately 72.8 mN/m millinewtons per meter .The drop weight method is a technique used to measure the surface tension of a liquid. Here's how it can be done:1. Prepare a clean, dry, and smooth glass or metal tube with a small diameter around 1-3 mm . The tube should have a smooth, well-rounded opening at the bottom.2. Fill the tube with the liquid water, in this case using a syringe or pipette. Make sure there are no air bubbles in the liquid.3. Allow the liquid to flow out of the tube under the force of gravity. As the liquid flows out, it will form a droplet at the bottom of the tube. The droplet will grow in size until the surface tension force can no longer support its weight, and the droplet will detach from the tube.4. Measure the mass of the detached droplet using a sensitive balance. This can be done by collecting the droplets in a container placed on the balance and recording the mass difference after each droplet falls.5. Repeat the process several times to obtain an average mass of the droplets.6. Calculate the surface tension using the formula: = mgd / 6R where m is the mass of the droplet, g is the acceleration due to gravity approximately 9.81 m/s , d is the density of the liquid, and R is the radius of the tube.7. The calculated value should be close to the known surface tension of water at room temperature, which is approximately 72.8 mN/m.Keep in mind that this method may not provide highly accurate results, as it is sensitive to factors such as temperature, impurities in the liquid, and the cleanliness of the tube. However, it can still give a reasonable estimate of the surface tension of water at room temperature.