I need help with all of these problems, but specifically #4 3Sr(NO3)2 + 2(NH4)3PO4 --> Sr3(PO4)2 + 6NH4NO3

4.) How many FORMULA UNITS of strontium nitrate are needed to react with 345 GRAMS of ammonium phosphate?​

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.