No, of course not. I can't give you a long drawn out answer but it is definitely not.
A metal Surface being ground is a physical change, not a chemical change.
chemical change
Resistance to corrosion is a chemical property.
Potatoes that are contain more starch than the average are used as boiling potatoes. The color of a potato does not dictate its use due to there being hundreds of varieties of potatoes. Potatoes that are ideal for making mashed potatoes are russet varieties (the majority of Idaho grown potatoes are russet, and Caribe. Yukon Gold, Peruvian Blue, Superior, Kennebec, and Katahdin are all purpose potatoes.
when milk curs it is a chemical change. A physical change is change in form, which is revesrable. Like water being frozen then thawed. A chemical change is irreversible, and involves a change in the chemical make up. What is happening is a new compound is being formed by the milk reacting with the air and such.
physical. the water being added simply soaks through the coffee, so there's no chemical change.
No. It is a physical change because the wheat's chemical composition does not change.
Gasoline being poured into a tank is not a chemical change.
Chemical
Here are some links to potato recipes on a fabulous cooking website called epicurious.com.You can search the recipe data bank using the word "potatoes" and find many more, but I can vouch for these three being very tasty and easy to prepare.http://www.epicurious.com/recipes/food/views/Thyme-Roasted-Sweet-Potatoes-233085http://www.epicurious.com/recipes/food/views/Garlic-Mashed-Potatoes-with-Chives-108582http://www.epicurious.com/recipes/food/views/Olive-Oil-Mashed-Potatoes-107604
burning of tree or wood is an irreversible chemical change
Tarnishing is a chemical change in which the metal is being oxidized.