What is the main reason that it takes 2 to 3 minutes for the reaction to occur between sucrose and sulfuric acid in the dehydration of sucrose?

 There is a time delay of almost two to three minutes before the reaction proceeds because of the following processes:

1)     The acid starts to go yellow as the dehydration begins.

2)     The rate of dehydration then accelerates as the acid heats up because the reaction is exothermic/chemical (releases energy by light or heat).  As the sugar molecules are stripped of water, the heat generated turns the water into steam which then expands the remaining carbon into a porous, smoking, black column.

3)    This expands out of the reaction vessel, producing a choking acrid vapor and the smell of burned sugar.

 At this stage, sulfuric acid is highly corrosive and will burn skin so one must avoid contact with it. 

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.

the answer is 0.8m.

by: nicholas