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3 marksReactions of Carbon Compounds

CSEC Chemistry · January 2012 · Paper 2 · Question 6(c)

Flour usually consists of 55–80% carbohydrates (starches). Iodine can be used to test for the presence of starches. There is no blue-black colouration when flour, which is stored in a hot, humid room for a long time, is tested with iodine.

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Other parts of this question

  1. 6(a)(i)Discuss the role of Water in the making of dough:[2 marks]
  2. 6(a)(ii)Discuss the role of Leavening agent (baking powder and yeast) in the making of dough:[2 marks]
  3. 6(a)(iii)Discuss the role of Heat in the making of dough:[2 marks]
  4. 6(b)Write THREE relevant chemical equations to support your answer in (a). Include AT LEAST ONE equation from the action of yeast and ONE from the action of baking…[6 marks]

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