Which of the following is NOT a clue that could indicate a chemical change? A. change in color
B. mixing reactants
C. change in energy
D. release of gas
E. formation of precipitate​

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

2-bromo-2-methylbutane undergoes an e1 elimination reaction in the presence of ethanol. in the next reaction only one of the possible products is represented. although the product shown is not the major product of the reaction, notice that there is more than one way it can be produced. complete the mechanism and draw the missing substances.

Just on number 2 (all parts), and if you do answer explain in detail