Biology 9700 · AS & A Level · Testing for biological molecules

Testing for biological molecules — practice question

Trehalose is a sugar that gives a negative result in a test with Benedict’s solution. If a molecule of trehalose is hydrolysed, it produces two $\alpha$-glucose molecules. Which row is the correct one?

  • Aformula of trehalose $\text{C}_{12}\text{H}_{22}\text{O}_{11}$; sugar that gives the same result with Benedict’s as trehalose: fructose
  • Bformula of trehalose $\text{C}_{12}\text{H}_{22}\text{O}_{11}$; sugar that gives the same result with Benedict’s as trehalose: sucrose
  • Cformula of trehalose $\text{C}_{12}\text{H}_{24}\text{O}_{12}$; sugar that gives the same result with Benedict’s as trehalose: fructose
  • Dformula of trehalose $\text{C}_{12}\text{H}_{24}\text{O}_{12}$; sugar that gives the same result with Benedict’s as trehalose: sucrose

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