Dissolving sugar in water is considered a physical change. It can be confusing because the crystals of sugar are no longer visible, but like I tell my students, it is still sugar in water not a brand new substance. The two can be separated with various methods, but they are the same substances that you started with. I’m order for a chemical change to occur there must a change in the bonds between the individual molecules of each substance. Chemical changes usually give off an odor, a sound, heat etc during the reaction.
Sugar dissolution in water is a physical change and not a chemical change because, when sugar is mixed in water, the water molecules break down the sugar molecules so, as a result sugar changes it's shape and gets dissolved in the water attaching the chain bonding between them.
Dissolving of sugar in water is considered a physical change. Even though the appearance has changed (from white crystals to invisible in the water) and the phase has changed, from solid to solution, it is a physical change, not a chemical change, because the bonds between atoms haven’t changed. The sugar is still sugar, and you can taste it in the water, and if you let the water evaporate, you will recover the sugar.
Dissolving of a solid to make a solution is one of the trickier changes, because it can show one of the signs we usually associate with chemical change. As you probably recall, these include color change, production of a new substance, such as a gas or solid precipitate, and production of heat or light. Some substances release heat when dissolved in water, giving a warm solution, and others absorb heat to yield a cold solution, but these are still physical changes. You can always get the solid back by letting the water evaporate, so it has not changed chemically.
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