Juice of tamarind turns blue litmus to red. It is because of the presence of a chemical compound called:
Step 1: Identifying the chemical compound. Tamarind juice is acidic due to the presence of tartaric acid, which is a weak acid.
Step 2: Conclusion. Therefore, the correct answer is tartaric acid.
Match the Compounds (List - I) with the appropriate Catalyst/Reagents (List - II) for their reduction into corresponding amines. 
Consider the following amino acid: 
Which of the following options contain the correct structure of (A) and (B)?
आपका घनिष्ठ मित्र दूसरे मुसीबत को, आपके घर में उसका स्वागत किस प्रकार करता है? विस्तार से लिखिए।