The physical meaning of density of substance is the value of its weight concluded in a certain volume. There is a set of methods of determination of this parameter. But one of them famous from school textbooks and based on effect of replacement of liquids by the solid bodies shipped in them, is allocated with the simplicity and sufficient accuracy. It is possible to determine by a similar way density, for example, flew down.
It is required to you
- - graduated cylinder;
- - studied glass;
- - exact (it is desirable electronic) scales;
- - water.
Instruction
1. Prepare everything, necessary for measurements. First of all you need a graduated cylinder and scales. The graduated cylinder has to have rather exact graduation, and scales to allow measurement of masses to within the tenth shares of gram. At the same time the graduated cylinder has to be established reliably on scales. Prepare glass which density needs to be measured. Its fragments have to be rather small. Therefore if it is necessary, crush glass before carrying out an experiment.
2. Begin an experiment on finding of density of glass. In a graduated cylinder approximately on a third pour water. Determine its volume by divisions of a scale. Then make weighing of a graduated cylinder with the liquid which is contained in it. Write down results of measurements, having designated the initial volume as V1, and mass of a graduated cylinder with water as m1.
3. Place a number of shredded glass in a graduated cylinder. It has to be enough as on weight and in order that water level considerably increased (it will reduce errors in calculations). Act carefully, placing glass in a graduated cylinder in the small portions. Use metal nippers or a shovel. Pay attention that liquid has to cover all particles of glass completely. Also between them there should not be vials of air. If they are available, several times stir up a graduated cylinder.
4. Perform repeated measurements. Again weigh a graduated cylinder and also learn the volume of its contents. Designate the found weight as m2, and volume as V2.
5. Determine glass density. Find the mass of the splinters placed in a graduated cylinder. As the weight of the device and liquid in it did not change, it will be equal to m2-m1. The volume of glass will be equal to the volume of the liquid which is forced out by it, that is V2-V1. Thus, density of glass can be calculated on a formula Ρ=(m2-m1)/(V2-V1).