Why Does Hot Water Freeze Faster than Cold Water?

What would happen if hot water is kept inside the freezer? Will it freeze faster than cold water? To understand the concept of the Mpemba effect, you can conduct science experiments for kids in order to teach how hot water evaporates into vapor and reduces its volume so that it can freeze faster than cold water. Why does hot water freeze faster than cold water? Besides evaporation, there are also other factors such as convection, supercooling, dissolved gas and the effect of surroundings that contribute to hot water freezing faster than cold water. 

Contents

To make children aware of the scientific concept of how hot water freezes faster than cold water, teach them about the factors that contribute to the freezing of hot water faster than cold water. Allow kids to experiment with cold and hot water to check which one of them freezes fast. This is one of the DIY science project ideas for kids in Kindergarten and elementary school. They would not only learn the concept of freezing but also upgrade their scientific knowledge with the help of experiments that they perform. 

How Does Hot Water Freeze Faster than Cold Water?

According to the Mpemba effect, when the cold and hot water are exposed to the same temperature, the hot water freezes faster than the cold water.  Take two containers with equal amounts of water with different temperatures, one should be hot and the other should be cold. The two water containers will be kept under the same temperature to freeze. Now, you need to figure out which container will freeze first.

Why does hot water freeze faster than cold water? To know the answer, you need to understand the mechanism of how hot water freezes first than cold water. Some of the factors responsible for hot water freezing in the first place are evaporation and convection. The former enables hot water to evaporate and reduces the volume of water so that it cools faster than cold water. Whereas, the latter develops convection currents in hot water by creating a difference in the temperature from top to bottom of the container. Besides this, there are other factors such as supercooling, the effect of surroundings and dissolved gas.  

Fun Facts about Why Does Hot Water Freeze Faster than Cold Water?

Some of the interesting facts about why hot water freezes faster than cold water are mentioned below:

  • The hot water freezes faster than cold water due to the Mpemba effect. 
  • The hot water freezes faster due to evaporation, convection and other factors. 
  • The hot water has less capacity to hold dissolved gases compared to cold water. 
  • During convection, the density of water decreases when the temperature increases. 
  • The hot water has more convection current than cold water. 
  • The Mpemba effect came into light when young Mpemba argued that slightly heated ice cream would freeze faster compared to cold ice cream. 

Easy Science Project: Why Does Hot Water Freeze Faster than Cold Water?

Have you ever tried tossing boiling or hot water into the air during the freezing temperature outside your home? If you’ve, then what did you observe? It basically creates snow out of it. Must say! It is a beautiful thing to watch. It happens when the hot water evaporates and loses its mass and eventually needs less time to cool and freeze compared to the cold water kept under the same conditions. Why does hot water freeze faster than cold water? You can teach the concept more easily to children with the help of an experiment.

Why Does Hot Water Freeze Faster than Cold Water?

Aim of the Project 

To experiment and observe how hot water freezes first compared to cold water using the materials available at home. 

Materials Required

  • Two containers
  • A cup of hot water 
  • A cup of cold water
  • Thermometer 
  • A paper and a pen

Procedure 

  • Take two containers and label it as A and B.
  • Pour a cup of hot water into container A. 
  • Then, pour a cup of cold water into container B. 
  • Record the temperature of both containers on a sheet of paper. 
  • Now, keep both the containers in the freezer for one hour. 
  • Remove the containers after one hour and record the observations. 

Result

It was observed that container A with hot water freezes faster than container B with cold water. This phenomenon is called the Mpemba effect. It usually occurs due to factors such as evaporation, convection, and along with other factors such as supercooling, dissolved gas and the effect of surroundings responsible for hot water freezing faster than cold water. 

Benefits of Learning about Why Hot Water Freezes Faster than Cold Water?

Some of the benefits of learning about the Mpemba effect are mentioned below:

  • Develops understanding of Mpemba effect in children.
  • Creates an interest to learn why hot water freezes than cold water by performing an experiment at home or in the classroom.
  • Develops creativity and visualization skills in children while performing an experiment. 
  • Boosts confidence to conduct more experiments in order to gain scientific knowledge on various topics. 
  • Helps in understanding the factors that enable hot water to freeze faster than cold water. 
  • Enhances the learning experience of children. 

To know more information, explore science games for kids, STEM activities for kids in the kids learning section at Osmo.

Frequently Asked Questions on Why Does Hot Water Freeze Faster than Cold Water?

Why does hot water freeze faster than cold water?

It is due to the Mpemba effect when the cold water evaporates and reduces the volume of water resulting in freezing faster compared to cold water. There are also other factors that contribute to hot water freezing faster than cold water is convection, dissolved gas, supercooling and the effect of the surrounding.

What are the benefits of learning about why hot water freezes faster than cold water?

The benefits of learning about why hot water freezes faster than cold water are that it helps children understand the phenomenon called the Mpemba effect and the factors responsible for making hot water freeze faster than cold water. Most importantly, it enables children to perform experiments to understand the concept in a much better way.