It depends on the freshness of an egg.
why does an egg float or sink in water
Bad eggs don't sink they float.
until you mix it
An egg will sink in water but will float in salt water. An egg will sink faster in hot water than it will in cold water.
float....when you boil an egg it starts out at the bottom and as the insides harden, making it ready for consumption, it will float.
The older an egg is the more likely it is to float. If it actually sits on the surface it may actually have gone bad.
It doesn't float or sink in the water that means that the egg has the same density as the water.
If the egg is good and not spoiled it will sink down. If the egg is spoiled it will float up.
Normaly if an egg floats it is bad and should be discarded. As the egg ages air pockets enter the egg, that's why they float. A change in buoyancy. If the egg is more dense then the water (or whatever liquid it is in), it will sink.
It sinks because the water is more dense than the egg in the water.
A Rock would obviously sink in water and a egg would float in salt water Believe it or not bowling balls that are denser than water float!
As the egg decomposes, the mass of the egg is reduced. This is because the egg shell is porous and water vapor and gases can escape over time, reducing the mass of the egg. If the mass of the egg is less than the mass of the volume of water displaced by the egg, it will float.