Density is the mass of 1 ml of a substance. In the previous experiment 1.0 ml of water was balanced by a paper weight of 1.0 g. This emans its density is 1.0 g/ml.
On a two pan scale you can compare the masses of 3 liquids, by putting an empty 1-ml syringe on each pan, taring and filling them with 1.0 ml of water samples.
For the following measurements a digitale pocket scale is used: The aluminium beaker of a tea light is tared. The first sample of 1.0 ml is added, weighed. After taring agin, the second 1.0 ml samples is added...
Material
Tray, digital pocket scale (VOLTCRAFT PS-20), Egyptian two pan scale with weights, clean aluminium beaker of a tea light, 3 labeled ampoules in stands, 3 sterile insulin syringes (1.0 ml/0.00 ml) without needles, methylated spirit, water, Dead Sea water (concentrated solution of Dead Sea salt).
Experiment
1. Take 3 labeled syringes, suck 1.0 ml of methylated alcohol ("alcohol"), of water and of Dead Sea water into them free of bubbles (Photo 1).
2. Tare the aluminium beaker on the digital scale (Photo 1), add 1.0 ml methylated spirit. Read the number (Photo 2) and tare. 3. Add 1.0 ml fresh water. Read the number (Photo 3) and tare again.
4. Add 1.0 ml Dead Sea water. Read the number (Photo 5).
Observations
Compare your results with those in Photos 2, 3, 5. Write them down. For Dead Sea, please click here.
Explanation
The density of a substance is one of the most important property of matter. The density of a substance depends on its mass and the composition of its particles.