The central theme across the sources is to deepen students' understanding of the various factors that affect how quickly liquids, specifically water, evaporate. The primary factors highlighted are:

• Surface Area: A larger surface area leads to a faster rate of evaporation.
• Temperature: Higher temperatures result in a quicker evaporation process.
• Humidity: Higher humidity in the surrounding air slows down evaporation.
• Presence of Wind: Wind increases the rate of evaporation.
• Pressure: (Mentioned in the title of one source but not elaborated upon in the provided excerpts).

The sources emphasize the use of an interactive HTML5 applet as a tool for students to explore these relationships through simulation and observation.

Key Ideas and Facts:

1. Interactive Simulation: The core of the learning resource is an embedded HTML5 applet that allows secondary school students to visualize and investigate the factors affecting evaporation. The embed code is provided:
2. <iframe width="100%" height="100%" src="https://iwant2study.org/lookangejss/03thermalphysics_10temperature/ejss_model_evaporationV2secomdarywithpressure/evaporationV2secomdarywithpressure_Simulation.xhtml " frameborder="0"></iframe>
3. Learning Goals: The applet and accompanying materials are designed to help students understand how surface area, temperature, humidity, and wind influence the rate of evaporation. The stated learning goal is to deepen students' understanding of these factors. The resource is also linked to the Pri 5 & 6 SCIENCE (2014) curriculum.
4. Impact of Surface Area: The documentation explicitly states the relationship between surface area and evaporation rate:

• "For a small surface area, the rate of evaporation of water in the container decreases with time"
• "For a large surface area at the beginning, the rate of evaporation of water in the container decreases with time in the blue trail. This implies larger the surface area the shorter the time taken to evaporate"

1. Impact of Temperature: The effect of temperature on evaporation is also clearly outlined:

• "For a low temperature, the rate of evaporation of water in the container decreases with time linearly in the red trail"
• "For a high temperature, the rate of evaporation of water in the container decreases with time linearly in the blue trail. This implies higher the surrounding temperature the shorter the time taken to evaporate"

1. Impact of Wind: The presence of wind accelerates evaporation:

• "For a low wind condition, the rate of evaporation of water in the container decreases with time linearly in the red trail"
• "This implies higher the wind the shorter the time taken to evaporate"

1. Impact of Humidity: Higher humidity inhibits evaporation:

• "For a low humidity condition, the rate of evaporation of water in the container decreases with time linearly in the red trail"
• "This implies higher the humidity the longer the time taken to evaporate"

1. Experimental Activities: The resource suggests hands-on or virtual experiments using the applet. One example provided involves:

• Changing the temperature in the simulation.
• Observing the graph of water amount over time.
• Recording the time taken for complete evaporation at different temperatures.
• Comparing the graphs to determine which temperature leads to faster evaporation.

1. Related Resources: The web page provides links to other relevant materials, including:

• An "Evaporation (Surface Area, Temperature, Humidity, Presence of Wind) for Primary School" resource.
• YouTube videos demonstrating evaporation experiments and the virtual labs. Links provided include:
• https://www.youtube.com/watch?v=4JIz7913EQU
• http://weelookang.blogspot.com/2020/06/evaporation-surface-area-temperature.html
• https://weelookang.blogspot.com/2022/02/evaporation-surface-area-temperature.html
• Links to lessons on the Singaporean Ministry of Education's learning platform (VLE).

1. Credits and Licensing: The applet is credited to Francisco Esquembre, Felix J. Garcia Clemente, Rena F, Zed, and ShiXiong (idea). It is licensed under the Creative Commons Attribution-Share Alike 4.0 Singapore License for non-commercial use. Commercial use of the underlying EasyJavaScriptSimulations Library requires contacting fem@um.es.
2. Target Audience: The primary target audience for this resource is secondary school students, although a related resource is available for primary school levels.

Potential Discussion Points/Further Investigation:

• While pressure is mentioned in the title of the secondary school resource, the provided excerpts do not elaborate on its effect on evaporation. Further investigation into this aspect might be beneficial.
• The resource utilizes graphs to represent the rate of evaporation over time under different conditions. Understanding these graphical representations is crucial for students.
• The links to external resources, particularly the YouTube videos and VLE lessons, could provide additional context and learning activities.

In conclusion, these sources provide a valuable open educational resource for teaching the factors affecting evaporation to secondary school students. The interactive simulation, coupled with clear explanations and suggested activities, offers a practical approach to understanding this scientific phenomenon.

Frequently Asked Questions about Evaporation

What is evaporation?

Evaporation is the process by which a liquid, such as water, changes into a gas or vapor. This occurs when molecules within the liquid gain enough kinetic energy to overcome the intermolecular forces holding them together and escape into the surrounding air.

What are the key factors that affect the rate of evaporation?

Several factors influence how quickly evaporation occurs. These include:

• Temperature: Higher temperatures provide more kinetic energy to liquid molecules, increasing the rate at which they can escape and become a gas.
• Surface Area: A larger surface area exposes more liquid molecules to the air, allowing for a greater number of molecules to evaporate at any given time, thus speeding up the overall process.
• Humidity: Humidity refers to the amount of water vapor already present in the air. If the air is already saturated with water vapor (high humidity), the rate of evaporation will be slower because there is less space for more water molecules to enter the gaseous phase. Conversely, dry air (low humidity) allows for a faster rate of evaporation.
• Presence of Wind: Wind or air movement helps to carry away water vapor molecules that have just evaporated from the liquid's surface. This prevents the air directly above the liquid from becoming saturated, allowing more molecules to evaporate and increasing the rate of evaporation.
• Pressure: While not explicitly detailed as prominently as the other factors in the provided text, lower atmospheric pressure generally leads to a faster rate of evaporation. This is because there is less external force pressing down on the liquid surface, making it easier for molecules to escape.

How does temperature affect the time it takes for water to evaporate?

Higher temperatures significantly decrease the time it takes for water to evaporate. The provided information states that at higher surrounding temperatures, the time taken for evaporation is shorter. This is because more water molecules have sufficient energy to break free from the liquid surface and become vapor.

In what way does surface area influence the rate of evaporation?

A larger surface area leads to a faster rate of evaporation and consequently a shorter time for the liquid to completely evaporate. The text explicitly mentions that with a larger surface area at the beginning, the time taken for the water to evaporate is shorter. This is because more molecules are exposed to the air and can escape simultaneously.

How does humidity in the air impact the evaporation process?

Higher humidity in the surrounding air slows down the rate of evaporation, thus increasing the time it takes for a liquid to evaporate completely. The provided text indicates that under high humidity conditions, the time taken for evaporation is longer. This is because the air already contains a significant amount of water vapor, reducing its capacity to hold more.

What role does wind play in the evaporation of a liquid?

The presence of wind or air movement increases the rate of evaporation and reduces the time required for a liquid to evaporate. The text states that with higher wind conditions, the time taken to evaporate is shorter. Wind helps to remove the water vapor that accumulates above the liquid's surface, preventing saturation and allowing more evaporation to occur.

Can you provide examples of how these factors interact in everyday life?

Yes, several everyday scenarios illustrate the interplay of these factors:

• Drying clothes on a clothesline: Clothes dry faster on a warm, sunny, and windy day (high temperature and wind, typically lower humidity) compared to a cool, still, and humid day. Spreading the clothes out (increasing surface area) also speeds up drying.
• Sweating: When we exercise, our body produces sweat to cool down. The evaporation of sweat from our skin is more effective on a dry and windy day because the low humidity and wind allow the sweat to evaporate quickly, taking heat away from our body. On a humid day, sweat evaporates more slowly, making us feel hotter and stickier.
• Water evaporating from a puddle: A shallow puddle (large surface area) will evaporate faster than a deep container with the same volume of water (smaller surface area). The rate will also be higher on a warm, breezy day than on a cool, still day.

What educational resources are available to further understand evaporation?

The provided text mentions several open educational resources, including:

• An interactive HTML5 applet for secondary school that allows exploration of the effects of pressure, surface area, temperature, humidity, and wind on evaporation.
• Links to specific scenarios demonstrating the effects of varying surface area, temperature, and wind conditions.
• A YouTube video demonstrating an experiment on the effect of temperature on the rate of evaporation.
• Links to virtual labs focusing on the impact of surface area, humidity, and wind on evaporation for primary school science.
• Additional resources and lessons available on learning platforms.