specific gravity
One practical application of finding a liquid's density (the ratio of a substance's mass to its volume) and specific gravity (the ratio of a liquid's density to the density of water) is urinalysis.
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Transcript
Why do some liquids float on top of others?
Because of differences in their densities.
Density is a ratio of a substance’s mass to its volume.
So if you know the mass and the volume of a substance, you can use this relationship to determine its density. Let’s find the density of 150 milliliters of a liquid that has a mass of 130 grams.
Divide the mass by the volume.
The liquid has a density of 0.87 grams per milliliter. Now--will this liquid float on water, or sink?
You can find out by determining the specific gravity!
Specific gravity is the ratio of the liquid’s density compared to the density of water, which is 1 gram per milliliter. So, divide 0.87 by 1.0 to get….0.87!
Liquids with a specific gravity of less than 1 will float on water, while those with a specific gravity greater than 1 will sink.
Your liquid floats! Specific gravity has many practical applications.
In medicine, it is an important component of urinalysis.
Normal urine is slightly denser than water. The normal range for the specific gravity of urine is 1.001 to 1.035.
If the specific gravity of a urine sample is above the normal range, it could indicate dehydration or heart failure...
...while a below-normal result could indicate any of several disorders from kidney disease to diabetes.