Percent composition of (NO3)-4

11. phosphorus-32 is radioactive and has a half life of 14 days. how much of a 124 mg sample of phosphorus-32 is present after 56 days? a) 7.75 mg b) 15.5 mg c) 31.0 mg d) 62.0 mg

Astudent made the lewis dot diagram of a compound as shown. mg is written with two dots shown on its top. an o is written on each side of mg. each o has six dots around it. an arrow is shown from one dot on mg toward the vacant space around the o on the right. another arrow is shown from the other dot on mg toward the vacant space around the o on the left. the title of the art is students lewis dot model. what is the error in the lewis dot diagram? an o atom should transfer all its six electrons to mg because the formula is mgo. both electrons of mg should be transferred to one o atom because the formula is mgo. the electrons should be transferred from each o atom to mg because mg has fewer electrons. the number of dots around mg should be four because it has to transfer two electrons to each o.

Assignment directions: pick one of the following chemists and perform a bit of research on him/her. answer the following questions. alice hamilton             rosalind franklin marie curie             gertrude b. elion ada yonath             henry cavendish robert boyle             antoine lavoisier mario j. molina             svante arrhenius