What must occur in a substance in order to determine a chemical property?

Answer;

-Change in the substance in presence of another;

Explanation;

-A chemical property can be determined only when a change in the substance occurs in the presence of another substance or when sufficient energy of some form is added to it.

-Chemical properties can be established by changing a substance's chemical identity, and are different from physical properties, which can be observed by viewing or touching a sample.

the tides are influenced by both the moon and the sun, it's easy to see that when the sun lines up with the moon and the earth, as during a new moon or full moon, the tidal effect is increased. these are known as spring tides, named not for the season, but for the fact that the water "springs" higher than normal. on the other hand, if the sun and the moon are 90 degrees apart in relation to an observer on earth as during the first quarter moon or third quarter moon, then high tides are not as high as they normally would be. this is because despite its greater distance, the sun's mass allows it to exert enough gravitational force on the oceans that it can negate some of the effects of the moon's pull. this phenomenon of lower high tides is called a neap tide. if you need more information on this topic visit moonconnection.com.