Announcing the winners!

(I edited the comment and added the title as now all questions are already answered.)

Finally some interesting answers were coming in. Let's make a little conclusion:

Concerning part a)

• 40 min is correct.
  Hive account@isnochys was the fastest and will receive 4 STEEM for that.

• 0.833 mol is correct.
  Hive account@isnochys found it first, which means 2 more STEEM.

• The number of molecules is 5.018∙10²³.
  Hive account@jedigeiss is correct here and will receive 2 STEEM.

Concerning part b):

• The density of the honey is 1.25 g/cm³.
  Hive account@isnochys was the fastest one and will get 4 STEEM.

Concerning part c):

• It is correct that per mol glucose an amount of 2808.4 kJ energy is released as Hive account@mcw pointed out (and earned 3 STEEM by doing so).
  However, one-tenth of the 500 g honey contains far less than 1 mol glucose, but a twelfth part of one mol. Thus the released energy ΔH_R = - 234.033 kJ as Hive account@jedigeiss found out - and earns 5 more STEEM.