No.
No, mixing cornstarch with water is not a chemical reaction. It is a physical change. The cornstarch particles disperse throughout the water, but no new substances are formed.
Well, there is no chemical reaction, really, since the cornstarch still remains cornstarch. (and if you dry it, it becomes cornstarch again) It's just that the cornstarch lightly bonds to the water which then lightly bonds to other cornstarch, creating a net-like substance. This net is easily broken and made, thus increasing the viscosity of the fluid and adding some other interesting properties to it as well.
No they do not.
No, because it just change to liquid
Cornstarch is hydrolysed with hot water (adding also a small volume of sulfuric acid).The product is glucose.
Neutralizing is a chemical change, as it involves a chemical reaction between an acid and a base to produce a salt and water. This reaction results in the formation of new substances with different chemical properties than the original acid and base.
It is a physical change.
No, only dissolving of KI but that is a physical change.
The absorption of water is not a chemical reaction.
Yes the chalk is turned into salt and water if there is enough vinegar
No, oobleck is typically made with cornstarch and water. Baking soda and water would not create the same non-Newtonian fluid consistency as cornstarch and water.
Water is not a reaction at all. If you mean to ask if a state change in water is chemical or physical, it is physical.