- - hydrometer;
- - table density of the substance;
- - scales;
- - graduated cylinder.
To measure the density of the liquid mixture take a hydrometer.Immerse it in the liquid so that it floats freely in it.At the top of the scale of the hydrometer is.Determine density mixture , combining scale with the bottom of the meniscus of the liquid in which it is immersed.
To calculate the density of the mixture weigh it on the scales.The value of the mass m will get in grams.Using a measuring cylinder, or otherwise, determine the volume of a weighed amount of mixture V. Measured in cc.Calculate the density mixture , dividing its mass per volume, ρ = m / V.The resu
lts were obtained in g / cm³.To put it in kg / m³, the result of multiply by 1000.
PrimerPri two metals smelting received 400 g of an alloy of 50 cc.Determine its density .Calculate the density from the formula ρ = 400/50 = 8 g / cc or 8000 kg / m³.
If you know the density of the substances to be mixed, and the volume, as it often occurs when mixing liquids, calculate the density of resulting mixture .Measure the volume of the mixture .It may look slightly different from the total volume of mixed liquids.For example, by mixing one liter of alcohol and 1 liter of water volume mixture is less than 2 liters.This is due to the molecular structure of these two liquids.
If the density of the mixed liquids are unknown, find their meaning in a special table.To calculate the sum of the products get 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.
PrimerPri mixing 1 liter of water and 1 liter of ethyl alcohol obtained 1.9 liters mixture .Determine its density .The density of water is 1 g / cc, alcohol - 0.8 g / cm³.Turn the unit volume: 1 l = 1000 cc, 1900 cc = 1.9.Calculate the density mixture of the two components of the formula for ρ = (ρ1 ∙ V1 + ρ2 ∙ V2) / V = (1 ∙ 1000 + 0,8 ∙ 1000) / 1900≈0,947 g / cm³.