Question
Download Solution PDFFoods with starch in them will turn blue-black when they come in contact with ________.
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFThe correct answer is iodine.Key Points
- Iodine is a chemical element that is used as an indicator to test for the presence of starch in food.
- When iodine comes in contact with starch, it forms a blue-black complex that is visible to the naked eye.
- This reaction is due to the formation of an amylose-iodine complex, which is a type of chemical bond between iodine and starch.
- Salt, blue litmus, and red litmus are not indicators of starch and do not react with it in any way.
Additional Information
- Iodine is a halogen element that is commonly used as an antiseptic, disinfectant, and nutritional supplement.
- It is also used in the production of dyes, photographic film, and other industrial applications.
- Blue litmus is an indicator that is used to test for the presence of acids in a solution.
- It turns red in the presence of acids and remains blue in the presence of bases or neutral solutions.
- Red litmus is an indicator that is used to test for the presence of bases in a solution.
- It turns blue in the presence of bases and remains red in the presence of acids or neutral solutions.
Last updated on Jul 8, 2025
-> The Staff Selection Commission released the SSC GD 2025 Answer Key on 26th June 2025 on the official website.
-> The SSC GD Notification 2026 will be released in October 2025 and the exam will be scheduled in the month of January and February 2026.
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