Neco Model Questions Vol1 2024 Biology Question 3

A student carried out a Benedict’s test to estimate the carbohydrate content of a commercial fruit juice. The procedure was: 1. Weigh 5.00 g of the juice. 2. Dilute with 10 mL distilled water and filter. 3. Pipette 2.00 mL of the filtrate into a test tube, add 2.00 mL of Benedict’s reagent and heat in a boiling water bath for 5 minutes. 4. Cool the mixture, filter the reddish‑brown precipitate, wash with a small amount of cold water and dry to constant mass. The mass of the dried precipitate (Cu₂O) was 0.108 g. The reaction stoichiometry is such that 1.0 g of Cu₂O corresponds to 5.0 g of reducing sugar present in the original sample. The juice label states that it contains 12 % (w/v) carbohydrate (i.e. 12 g per 100 mL). The density of the juice is 1.05 g mL⁻¹. Using the data above, answer the following: