Summary of Everyday Materials Transformations

Goals

1. Understand how common materials change when they experience different conditions.

2. Identify specific changes in materials when exposed to heat, cold, light, and humidity.

Contextualization

Think about how our daily lives would look without the items we rely on, like mugs, clothing, toys, and even the food we eat. Most of these everyday objects undergo a variety of transformations to become useful and safe for us. These changes can take place due to heat, cold, light, and moisture. Grasping how these factors affect materials helps us make sense of the world around us and come up with innovative solutions for common issues. For instance, glass can be crafted into different shapes when heated, and chocolate turns liquid when heated but returns to a solid state when cooled.

Subject Relevance

To Remember!

Material Transformation through Heating

Heating involves transferring thermal energy to a material, which leads to physical and chemical changes. Different materials react differently to heat. For example, chocolate melts when heated, while glass can be moulded into various shapes at high temperatures.

• Heating can change the shape and texture of materials.

• Materials like chocolate and glass have distinct melting points.

• The heating process is employed in various industries, including glass-making and food production.

Material Transformation through Cooling

Cooling is the removal of heat from a material, resulting in physical and chemical changes. Materials that have melted can solidify again upon cooling. For instance, chocolate melts when heated and hardens when cooled.

• Cooling can solidify materials that have melted.

• The cooling temperature is crucial in determining the final texture of the material.

• This process is widely used in the food industry and the production of materials like plastics.

Effect of Light on Materials

Light can impact materials in various ways, including colour changes, degradation, and chemical alterations. For example, strong light can fade the colour of paper or affect the integrity of some plastics.

• Light can cause chemical changes in materials, such as photodegradation.

• Materials exposed to sunlight can fade or lose their physical properties.

• Industries use UV protection to maintain the quality of light-sensitive materials.

Effect of Humidity on Materials

Humidity can influence materials in several ways, such as causing swelling, deformation, or weakening. Materials like paper and wood are particularly affected by humidity, which can compromise their structure and durability.

• Humidity can lead to swelling and deformation in materials like paper and wood.

• Extended exposure to humidity can cause deterioration and fungal growth.

• Protection against humidity is crucial across various industries, including construction and food storage.

Practical Applications

• In glass-making, heating shapes the material into things like bottles and window panes.

• In the food sector, cooling is used to set chocolates and ice creams after processing.

• UV protection is applied to plastics and paints to prevent damage from sunlight.

Key Terms

• Heating: The process of transferring thermal energy to a material.

• Cooling: The process of removing heat from a material.

• Photodegradation: The breakdown of materials due to light exposure.

• Humidity: The presence of water or water vapour in the air or within materials.

Questions for Reflections

• How can understanding material transformations help us create products that are more durable and efficient?

• Can you think of other materials that change due to heat, cold, light, or humidity in your everyday life?

• How can knowledge of these transformations assist in solving practical problems in the workplace?

Home Observation Challenge

To consolidate your understanding of material transformations, you'll conduct a simple experiment at home.

Instructions

• Select a common material in your house, such as a candle, a piece of chocolate, or a sheet of paper.

• Subject the material to one of the conditions studied: heat, cold, light, or humidity.

• Observe and document the changes that occur in the material. Take photos or create drawings of the transformations.

• Write a short report detailing the chosen material, the condition it was exposed to, and the changes observed.

• Share your findings with the class in the next lesson.