Answer:
, 
Explanation:
The change in energy is given by the change in gravitational potential energy:



The average rate of change in terms of time is approximately this:



Answer:
a solution color becoming less intense due to dilution- is not an evidence of a chemical reaction
bubbles (gas formation) - evidence of a chemical reaction
explosion or fire - evidence of a chemical reaction
changes in color- evidence of a chemical reaction
precipitation- evidence of a chemical reaction
changes in temperature - evidence of a chemical reaction
a solid liquifying - is not an evidence of a chemical reaction
solution colors mixing - is not an evidence of a chemical reaction
Explanation:
A chemical change is not easily reversible and yields new substances. It is often accompanied by a loss or gain of heat.
In the answer section, i have shown some evidences that lead us to conclude that a chemical reaction has taken place. The occurrence of a chemical change often goes with the formation of new substances as earlier stated and any of these signs may accompany the process.
For instance, when a metal is dropped in dilute acid solution, bubble of hydrogen gas indicates that a chemical reaction has taken place.
Answer:
See explanation
Explanation:
A. Constitutional or structural isomers have the same molecular formula but different structural formulas.
B. Conformational isomers are compounds having the same atom to atom connectivity but differ by rotation about one or more single bonds.
C. Stereo isomers are compounds having the same molecular mass and atom to atom connectivity but different arrangement of atoms and groups in space.
I. Enantiomers are stereo isomers (optical isomers particularly) that are non-superimposable mirror images of each other.
II. Diasteromers are optical isomers that are not mirror images of each other.
Both diasteromers and enantiomers are types of optical isomers which in turn is one of the types of stereo isomers.
Stereo isomers differ from conformational isomers in that the arrangement of atoms in stereo isomers is permanent while conformational isomers results from free rotations in molecules about single bonds.
Gain or lose.
The exchange of electrons in chemical bonding seeks to fulfill the octet rule. There are some exceptions, such as with hydrogen and helium, whose valence shells have a capacity of two electrons.