When 1 litre of water is cooled from 4°C to 0°C, its volume _____.

Question

Question

This question was previously asked in

RRB ALP Electrician 22 Jan 2019 Official Paper (Shift 1)

Answer 1

The correct answer is increases.

Important Points

In normal cases, the volume of substances increases on heating and decreases while cooling.
When 1 litre of water is cooled from 4°C to 0°C volume of water will start increasing this due to water's unique property known as 'Anomalous Expansion of Water'.
Anomalous Expansion of Water occurs between 4°C to 0°C.
The density of water is a maximum at 4 °C.
When water is cooled from 4°C to 0°C, its density decreases.
The anomalous expansion of water helps preserve aquatic life during very cold weather.

Explanation:

When water reaches 4°C the molecules have been pushed as close to one another as possible and the density of water becomes precisely 1.00 g/cm³
When water freezes at 0°C due to the crystal structure the molecules arranged in some structured fashion so a little far apart ended up less dense - 0.93 g/cm³ - and so floats due to buoyancy.

As density decreases the volume increases.

Volume = mass /density.

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