The molecules in water speed up and expand then the sugar slips in the space
Sugar should dissolve faster in a liquid.
Factors that cause sugar to dissolve faster include increasing the surface area of the sugar (finer crystals dissolve faster), stirring or agitating the solution, raising the temperature of the solvent (hot water dissolves sugar faster than cold water), and increasing the concentration of the solvent (higher concentration can dissolve more sugar).
The sugar cube in the hot water will dissolve faster because there are more and higher energy collisions between the water molecules and the sugar molecules which will cause the sugar to dissolve faster.
It isn't really a matter of what would dissolve first, as it is which dissolves faster. Both would dissolve at the same time, but the sugar would dissolve faster, and in higher quantities. Sugar has a solubility of 211.5 g/100 mL of water where salt only is ~37 g/ 100 mL. Sugar still dissolves faster even though apple juice has 10.8 g of sugar per 100 mL, since the solubility is as high as it is, sugar would dissolve first.
The difference is minimal; the white sugar dissolve a bit faster beacause doesn't contain impurities.
Yes
Sugar is less dense than salt, leading to it dissolving faster.
Sugar dissolves faster than salt in water. Salt has stronger bonds than sugar. That what makes sugar dissolve faster (because it has weaker bonds and structure than salt)
M&Ms dissolve faster in water than in soap because water has a higher solubility for sugar compared to soap. Soap molecules are more attracted to fats and oils, making them less effective at dissolving sugar.
No
Heat it
Sugar is more soluble.