Question

Four students recorded their data in the experiment done to detect the presence of metanil yellow in the adulterated arhar dal. Student Procedure Observation Inference I 5 g dal + 5 g metanil yellow Dal turns yellow Metanil yellow is present II 5 g dal + 5 ml water + 2 drops of HCl Solutions turns pink Metanil yellow is present in the sample III 5 g dal + 5 ml water + a pinch of metanil yellow Water turns yellow Metanil yellow is present IV 5 g dal + 5 ml water + 2 drops of HCl Water turns yellow and then pink Metanil yellow is absent which recording has been correctly reported by student:

Answer 1

Answer:

MATERIALS REQUIRED

Samples of food material (boiled rice or boiled potato), test tubes, test tube holder, iodine solution, distilled water.

THEORY

Starch is a complex carbohydrate which consists of many glucose molecules. It gives blue-black colour with iodine solution.

PROCEDURE, OBSERVATION AND INFERENCE

CBSE Class 9 Science Practical Skills – Food Sample Test for Starch and Adulteration 1

RESULT

The given food sample (rice/potato) contains starch.