Search results
Results from the WOW.Com Content Network
Pure water containing no exogenous ions is an excellent electronic insulator, but not even "deionized" water is completely free of ions. Water undergoes autoionization in the liquid state when two water molecules form one hydroxide anion (OH −) and one hydronium cation (H 3 O +). Because of autoionization, at ambient temperatures pure liquid ...
As a result, more water is forced into the container from another inlet creating a fountain effect. The demonstration introduces concepts like solubility and the gas laws at entry level. An ammonia fountain demonstration. A different gas of comparable solubility in water, such as hydrogen chloride, can be used instead of ammonia. [2]
To simplify comparisons of density across different systems of units, it is sometimes replaced by the dimensionless quantity "relative density" or "specific gravity", i.e. the ratio of the density of the material to that of a standard material, usually water. Thus a relative density less than one relative to water means that the substance ...
where g is the local acceleration due to gravity, V is the volume of the sample and of water (the same for both), ρ sample is the density of the sample, ρ H 2 O is the density of water, W V represents a weight obtained in vacuum, is the mass of the sample and is the mass of an equal volume of water. The density of water and of the sample ...
Dew is small drops of water that are condensed when a high density of water vapor meets a cool surface. Dew usually forms in the morning when the temperature is the lowest, just before sunrise and when the temperature of the earth's surface starts to increase. [103] Condensed water in the air may also refract sunlight to produce rainbows.
Example 1: If a block of solid stone weighs 3 kilograms on dry land and 2 kilogram when immersed in a tub of water, then it has displaced 1 kilogram of water. Since 1 liter of water weighs 1 kilogram (at 4 °C), it follows that the volume of the block is 1 liter and the density (mass/volume) of the stone is 3 kilograms/liter.
A Cartesian diver or Cartesian devil is a classic science experiment which demonstrates the principle of buoyancy (Archimedes' principle) and the ideal gas law.The first written description of this device is provided by Raffaello Magiotti, in his book Renitenza certissima dell'acqua alla compressione (Very firm resistance of water to compression) published in 1648.
A common example is the removal of water generated during a reaction in boiling toluene. An azeotropic mixture of toluene and water distills out of the reaction, but only the toluene (density 0.865 g/ml) returns, since it floats on top of the water (density 0.998 g/ml), which collects in the trap. Some high-boiling liquids that have an ...