Draw a mechanism for this reaction: 02 0 0 0 201 Br-Br 8? HO–CH, Draw all missing reactants and/or products in the appropriate boxes by placing atoms on the canvas and connecting them with bonds. Add charges where nee Electron-flow arrows should start on the electron(s) of an atom or a bond and should end on an atom, bond, or location where a new bond should be created. QQ H CH₂ 5 CH, Sund I UZ H

To help farmers and gardeners, commercial fertilizers have a big three-number "NPK" label on the bag that gives the amounts of three key plant nutrients: nitrogen, phosphorus and potassium. For example, a bag of "10-10-10" fertilizer has 10% by mass nitrogen, 10% by mass potassium as potash (K₂O), and 10% by mass phosphorus as phosphate (P₂05). Suppose a certain fertilizer has the following composition: ingredient ammonium phosphate ((NHÂ)¸PO4) ((NH,),CO) potassium sulfate (K,SO4) urea inert ingredients percent by mass 14% 36% 44% 6% What should the first (nitrogen) number on the bag label be? That is, calculate the percent by mass of nitrogen in this fertilizer. Round your answer to the nearest percent.

Element X has two isotopes, 28Q and 30Q. The relative atomic mass of X is 28.24. (a) Define the term "isotope". (b) Calculate the relative abundance of 28Q.

#69 a, b and c