It has more surface area.
The granules of icing sugar are more fine than granular sugar. The smaller the particles, the faster it dissolves.
it actually doesn't dissolve faster that other sugars. caster sugar dissolves faster than icing sugar because icing sugar will stick together in the water and as for caster sugar, the grains are small and so melt quicker!
The rate of dissolution is affected by the surface area of the solute coming into contact with the solvent. When powdered sugar is added to water, it can dissolve quickly because the particles are very small. Crystalline sugar has large particles. For two equal masses of powdered and crystalline sugar, the powdered sugar has much more surface.
Icing sugar shouldn't dissolve unless used in a very small amount because it contains chemicals that cause it to stick together when it's in water.
It has more surface area.
Dissolving will depend on surface area. Castor sugar has a smaller particle than regular sugar. The smaller the particle the larger the surface area. Surface area: Regular sugar < castor sugar < icing sugar. Castor sugar should dissolve faster than the same mass of regular sugar but slower than the same mass of icing sugar.
Faster. Because the hotter/warmer the substance, the faster ink or any other material would dissolve in it.
Not really; sugars other than powdered do not dissolve when used in a mixture that is not heated (such as icing). If the recipe already involves brown sugar, you can increase the quantity slightly without too many side-effects. However replacing powdered sugar (completely) with brown is likely to yield undesirable results; powdered sugar helps add 'smoothness' to icing, so without this you may end up with a very brown granular icing (that may not set adequately). If the recipe does not call for brown sugar at all, definitely do not add it.
The hotter it is the faster the molecules will move away from each other
It doesn't. The amount of time it takes for a tablet to dissolves depends on the tablet brand. Some brand names dissolve faster but some other tablets can dissolve faster.
Because it is hydrophilic...."water-loving." Examples of these are sugars, salts and ions. :)
No, sugars are polar molecules considering that they will interact and dissolve in water (which is also a polar molecule). Polar molecules will only interact with other polar molecules and vice-versa.
Sugar dissolves in a liquid faster than salt does. The reason is that sugar is less dense as a solute than salt is, leading to it dissolving in the solvent faster as it would fit into the 'empty gaps' that the solvent has at a much faster rate, which is how substances dissolve.
Fondant goes over icing that has been on a cake in the fridge.
In hot water the water molecules are moving at a faster rate than they move in cold water. The faster moving molecules hit the salt molecules with greater force and knock them away from the other salt molecules faster. That way the salt molecules dissolve in the water quicker.
Brown sugar is soluble in water- and it's solubility increases as the temperature increases (i.e. the hotter the water, the more brown sugar will dissolve!) This is why you can put brown sugar in your tea- while it is hot, it will all mix in, but if you make it with cold water, much less will dissove.
As a general rule the solubility of solids in water or other solvents is improved raising the temperature.