Quick science question! need instant !

a scoop of baking soda is added to a beaker containing vinegar. the baking soda disappears and bubbles are observed. this is an example of a change.
a) chemical
b) ionic
c) phase
d) physical

Which of the following warnings would an agricultural chemist tell a farmer who wants to recycle his or her own ammonia? recycling ammonia is a difficult process that sometimes takes weeks. recycling ammonia requires a degree in biochemistry or a related field. recycling ammonia can be harmful because it is highly flammable and toxic. recycling ammonia costs too much money considering the price of the necessary chemicals.