Which statement describes the law of constant composition (definite proportions)? mass in an isolated system is neither created nor destroyed by chemical reactions. all samples of a given chemical compound will be composed of the same elements in the same proportion. when two elements react to form multiple compounds, the different masses of one element that combine with a fixed mass of the other element can be expressed as a ratio of whole numbers. energy cannot be created or destroyed, but may be changed from one form to another. for a collision occurring between two particles in an isolated system, the total momentum of the two particles before the collision is equal to the total momentum of the two particles after the collision.

All samples of a given chemical compound will be composed of the same elements in the same proportion.

Explanation:

The law of constant composition or definite proportions states that "all pure samples of the same chemical compound contain the same proportions of the elements by mass". For example, every time water H₂O forms, it would always  have the same proportion of hydrogen and oxygen.

mechanics (greek   is that area of science concerned with the behaviour of physical bodies when subjected to forces or displacements, and the subsequent effects of the bodies on their environment. the scientific discipline has its origins in ancient greece with the writings of aristotle and archimedes[1][2][3] (see history of classical mechanics and timeline of classical mechanics). during the early modern period, scientists such as galileo, kepler, and newton laid the foundation for what is now known as classical mechanics. it is a branch of classical physics that deals with particles that are either at rest or are moving with velocities significantly less than the speed of light. it can also be defined as a branch of science which deals with the motion of and forces on objects. the field is yet less widely understood in terms of quantum theory.

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