Please help #1, #2, #3 I do not understand how to do them

Aperfume bottle is dropped in the corner of a room. the odor of the perfume can be detected on the other side of the room. which statement best describes this observation?

Dumbledore decides to gives a surprise demonstration. he starts with a hydrate of na2co3 which has a mass of 4.31 g before heating. after he heats it he finds the mass of the anhydrous compound is found to be 3.22 g. he asks everyone in class to determine the integer x in the hydrate: na2co3·xh2o; you should do this also. round your answer to the nearest integ

Chemical bonds result from the interaction of the from two or more atoms. a. protons b. electrons c. neutrons d. nuclei