안녕하세요 
네 맞습니다. water 가 polarity가 있어서 positively, negatively charged 인 ions을 잘 dissolve  ( MIX WELL) 한다는 뜻입니다. 

그리고 chemical reaction 일어날수있는 좋은 매질 ( medium) 인데요 
chemical들이 물에 잘 녹아있는 상태에서 다른 chemical들과 만나서 새로운 product을 만들수있고, 아래 이유로 chemical reaction이 잘일어난답니다.  

Water As a Medium for Chemical Reactions

Water is required for even the most basic chemical reactions. Proteins fold into their functional shape based on how their amino-acid sequences react with water. These newly formed enzymes must conduct their specific chemical reactions in a medium, which in all organisms is water. Water is an ideal medium for chemical reactions as it can store a large amount of heat, is electrically neutral, and has a pH of 7.0, meaning it is not acidic or basic. Additionally, water is involved in many enzymatic reactions as an agent to break bonds or, by its removal from a molecule, to form bonds.

이해가 되었는지요? 화이팅입니다 :)