Consider dissolving sugar in water and magnesium sulfate in water. is any new substance being produced? what happens after sodium hydroxide is added to the dissolved magnesium sulfate? does the addition of sodium hydroxide cause a new substance to appear? if so, what evidence shows this?

Here's what I get  

Explanation:

1. Sugar

(a) Dissolving in water

The white solid dissolves in water to give a colourless solution. There is no evidence that a new substance is being produced.

(b) Addition of sodium hydroxide

Adding the colourless solution of sodium hydroxide to the colourless sugar solution gives a colourless solution. There is no evidence that a new substance is being produced.

2. Magnesium sulfate

(a) Dissolving in water

The colourless crystals dissolve in water to give a colourless solution. There is no evidence that a new substance is being produced.

(b) Addition of sodium hydroxide

Adding the colourless solution of sodium hydroxide to the colourless solution of magnesium sulfate gives a white precipitate (see image). This is evidence that a new substance is being produced.

it is the most commonly accepted one