OH- is the ion that increases the concentration of a base
Answer:
Your answer will be b(molten material from the outer core makes its way to the surface of earth)
Explanation:
I would say it is a chemical change because after a while, the nails start to rust. Now they only rust after about a week though. But rust is a chemical change.
A and b are related because if u look carefully at what its showing u that there both the same but what its telling u is not the same.
a and c are the same but the picture is different and also the way they describe it is different and what they want u to look at is that if you look at it closely then youll know the difference and how to find it as well