Answer:
All of the above.
Explanation:
Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances.
This process is not reversible and a change of energy that is sometimes heat is given off.
In the case of the liquid meniscus, a concave meniscus that is what one usually observes takes place when the molecules of the liquid are fascinated towards the container. This takes place with water and a glass tube. A convex meniscus takes place when the molecules exhibit a stronger attraction with each other in comparison to the container, as in the case of glass and mercury.
The shape of the liquid meniscus is determined by the relative magnitudes of the cohesive forces in the liquid and adhesive forces between the liquid and its container.
The Earth's gravitational force accelerates objects when they fall. It constantly pulls, and the objects constantly speed up.