I forgot, and it's for my science fair project. It's due tomorrow, and I really need to know. Please give accurate information~! Does the object inside it float or sink?
My grade dropped from a B+ to a C- (darn test) and my science project could raise my grade by 2 grades!
My grade dropped from a B+ to a C- (darn test) and my science project could raise my grade by 2 grades!
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An object will float in a fluid (gas or liquid) if it's average density is less than that of the fluid. That works for gasses (helium balloons rise) or liquids (bubbles rise). So, increased density of the water means that denser objects will float.
Adding table salt to water increases the density of the water, by up to about 35% at room temperature but not usually anywhere near that. Ocean water is about 2-3% more dense than fresh water, for example.
The classic demonstration uses a raw egg, which is slightly denser than fresh water. Place the egg in a glass of fresh water and it sinks. Add salt (a tablespoon ought to be enough) and after enough salt dissolves, the egg will rise. Gently stir while adding salt to speed things up.
The egg rises and floats when the surrounding density is greater than that of the egg.
For an interesting experiment (doesn't look like you have time, though) you can try to dump the salt in at once into the water before adding the egg, gently. The salt will dissolve slowly and you can create a salinity difference between the bottom and top of the glass. As this occurs, the egg will rise to the level where it equals the salinity of the water and stay there.
That will tell you something not only about density, but about the rate of dissolution of the salt.
Adding table salt to water increases the density of the water, by up to about 35% at room temperature but not usually anywhere near that. Ocean water is about 2-3% more dense than fresh water, for example.
The classic demonstration uses a raw egg, which is slightly denser than fresh water. Place the egg in a glass of fresh water and it sinks. Add salt (a tablespoon ought to be enough) and after enough salt dissolves, the egg will rise. Gently stir while adding salt to speed things up.
The egg rises and floats when the surrounding density is greater than that of the egg.
For an interesting experiment (doesn't look like you have time, though) you can try to dump the salt in at once into the water before adding the egg, gently. The salt will dissolve slowly and you can create a salinity difference between the bottom and top of the glass. As this occurs, the egg will rise to the level where it equals the salinity of the water and stay there.
That will tell you something not only about density, but about the rate of dissolution of the salt.
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"high density" is a statement that is meaningless to me. Please tell me what you mean by "high" and "low" density...i.e. DEFINE A CUTOFF for me.