The indicator phenolphthalein turns pink in: MCQ with Answer and Explanation

Explanation:
Chlorophyll, the green pigment in plants, contains a magnesium ion (Mg²⁺) at the center of the porphyrin ring. It's essential for photosynthesis. Haemoglobin in blood contains iron. Calcium is in bones. Sodium is in body fluids.

Explanation:
The Ostwald process is used to manufacture nitric acid. The first step involves the catalytic oxidation of ammonia (NH3) to nitric oxide (NO). This reaction is carried out at about 800°C using a platinum-rhodium gauge catalyst. Iron is used in the Haber process, and V2O5 in the Contact process.

Explanation:
Chromatography separates components of a mixture based on differential affinities between a stationary phase and a mobile phase. In paper chromatography, dyes separate due to different rates of movement. Distillation is for liquids, centrifugation for density-based separation, filtration for solids from liquids. Chromatography is used in forensics, drug testing, and food coloring analysis.