Describe an experiment to show that water has maximum density at `4^(@)`. What important cosequences follow from this peculiar property of water? Discuss the importance of this phenomenon in nature.

Describe an experiment to show that water has maximum density at 4^@C .

Water has maximum density at 4°C.

Water has maximum density and minimum volume at 4^(@)C. Explain.

How is aquatic life benefitted by the fact that water has maximum density at 4°C ?

How is heavy water prepared from ordinary water ? Discuss its important physical and chemical properties.

A: Density of water is maximum at 4^(@)C . R : Water has both positive and negative temperature coefficients of volumetric expansions depending on the temperature range.

Which of the following statements regarding eutrophication are correct ? (i) Eutrophication is the natural ageing of a lake by nutrient enrichment of its water. (ii) Pollutants from human activities like effluents from the industries and homes can radically accelerate the aging process of a lake. This phenomenon is called as cultural or accelerated eutrophication. (iii) The plant nutrients responsible for eutrophication are nitrates and phosphates. (iv) These phosphates and nitrates accelerate the growth of algae, which utilise oxygen and may deoxygenate the water to kill the fish and other aquatic animals.

Define transpiration. Describe a simple experiment to demonstrate this phenomenon. In what way is transpiration important for plants ?

The alkene limonene has the following structure. What product results from the reaction of limonene and chlorine water ?

A student puts his pencil into an empty trough and observes the pencil from the position as indicated in Figure. (i) What change will be observed in the appearance of the pencil when water is poured into the trough? (ii) Name the phenomenon which accounts for the above stated observation. (iii) Complete the diagram showing how the student's eye sees the pencil through water.