You will need
- - hydrometer;
- - table of densities substances;
- - scales;
- - measuring cylinder.
To measure the density of the liquid mixture , take a hydrometer. Soak it in liquid so that it freely floated in it. At the top of the hydrometer is a scale. Determine the density of the mixture, combining the scale with the bottom edge of the meniscus of the liquid in which it is immersed.
To calculate the density of the mixture weigh her on the scales. The value of the mass m will get grams. Using the graduated cylinder, or other means, determine the amount of weighted number of compound V. the Measurement are produced in cm3. Calculate the density of the mixture, dividing its mass by the volume ρ=m/V. the Result is in g/cm3. In order to convert it in kg/m3, multiply the result by 1000.
Primeri melting the two metals received 400 g of alloy, with a volume of 50 cm3. Determine its density. Calculate the density according to the formula ρ=400/50=8 g/ cm3 or 8000 kg/m3.
If you know the density of the substances to be mixed, and their amounts, as often occurs when mixing the liquids, calculate the density of the resulting mixture. Measure the volume of the mixture. It may differ slightly from total volume of mixed liquids. For example, when mixing 1 liter of alcohol and 1 liter of water the volume of the mixture is less than 2 liters. This is due to the molecular structure of these two liquids.
If the density of the miscible fluids is unknown, find their value in the special table. To calculate, find the sum of the products of the density of each of the liquids on its volume ρ1∙V1+ ρ2∙V2+ ρ3∙V3+... etc the resulting value divide by the total volume of the mixture V, ρ=(ρ1∙V1+ ρ2∙V2+ ρ3∙V3+...)/V.
Primeri mixing 1 liter water and 1 liter of ethyl alcohol received 1.9 l of the mixture. Determine its density. The density of water is 1 g/ cm3, alcohol 0.8 g/cm3. Put the units of volume: 1 l=1000 cm3 and 1.9=1900 cm3. Calculate the density of the mixture using the formula for two components ρ=(ρ1∙V1+ ρ2∙V2)/V=(1∙1000+ 0,8∙1000)/1900≈0,947 g/cm3.