Question

Construct a circle graph for the composition of air. \(78.08 \% \mathrm{N}, 20.95 \% \mathrm{O}_{2}\) . 0.93\(\% \mathrm{Ar}\) , and 0.04\(\% \mathrm{CO}_{2}\) and other gases.

Short answer

To create a circle graph representing the composition of air, first convert the percentages of each gas into degrees as follows: Nitrogen (N) = \(280.69°\), Oxygen (O2) = \(75.42°\), Argon (Ar) = \(3.35°\), and Carbon dioxide (CO2) and other gases = \(0.14°\). Then, draw a circle, mark a starting point, and use a protractor to mark the angle measure for each gas composition in degrees, moving clockwise. Connect the endpoints of angle measures to the center of the circle, label each section with the corresponding gas composition and percentage, and the graph is complete.

Step-by-step solution

Convert percentages to degrees

To convert the percentage composition of each gas into degrees for the circle graph, we need to multiply each percentage by 360° (since a full circle represents 100%). Degrees for each gas: 1. Nitrogen (N): \(78.08 \% \times 360° = 280.69°\) 2. Oxygen (O2): \(20.95 \% \times 360° = 75.42°\) 3. Argon (Ar): \(0.93 \% \times 360° = 3.35°\) 4. Carbon dioxide (CO2) and other gases: \(0.04 \% \times 360° = 0.14°\)

Draw the circle graph

To draw the circle graph, follow these steps: 1. Draw a circle using a compass. 2. Mark a starting point on the circle, usually at the top or the right side. 3. Using a protractor, mark the angle measure for each gas composition in degrees, starting from the initial point and moving clockwise. 4. Complete the section for each gas by connecting the endpoints of angle measures to the center of the circle. 5. Label each section with the corresponding gas composition and percentage. With the degrees for each gas component calculated, you can now draw the circle graph: 1. Nitrogen (N): 280.69° 2. Oxygen (O2): 75.42° 3. Argon (Ar): 3.35° 4. Carbon dioxide (CO2) and other gases: 0.14° Following these steps will create a circle graph (pie chart) representing the composition of air.

Key concepts

Composition of Air

Air is made up of a variety of gases, each contributing to the air we breathe every day. The major component is nitrogen, which makes up about 78.08% of the atmosphere. Following nitrogen, oxygen is the second most abundant at approximately 20.95%. These two elements are crucial for supporting life on Earth.
Argon is another constituent, although much less in quantity, comprising only 0.93% of air. Carbon dioxide and other gases together form a small fraction of just 0.04%.

• Nitrogen (N₂): Vital for plant growth and a significant component of the Earth's atmosphere.
• Oxygen (O₂): Essential for respiration in animals and combustion processes.
• Argon (Ar): A noble gas used in fluorescent lights and arc welding.
• Carbon Dioxide (CO₂): Important for photosynthesis and a key gas in climate regulation.

Understanding this composition gives insights into environmental and atmospheric studies.

Percentage Conversion

To effectively represent data in a circle graph, it's necessary to convert percentages into degrees. This is because a circle graph, sometimes called a pie chart, utilizes the 360-degree circle to portray different data segments proportionally.
Here's how to convert a percentage into degrees:

• Identify the percentage value of the data you want to represent. For instance, nitrogen makes up 78.08% of air.
• Multiply the percentage by 360° to get the equivalent degree value. This means you take 78.08 and multiply it by 360, resulting in about 280.69° for nitrogen.
• Repeat this calculation for all components:
  • Oxygen: 20.95% × 360° = 75.42°
  • Argon: 0.93% × 360° = 3.35°
  • Carbon dioxide and other gases: 0.04% × 360° = 0.14°

This conversion ensures that each portion of the circle graph is proportionate to the actual significance or contribution of each component.

Circle Graph Construction

Constructing a circle graph (or pie chart) involves a few meticulous steps that result in a visual representation of data proportions. Here’s a simple guide to create one:

• Start by drawing a circle with a compass to ensure evenness.
• Choose a starting point on the circle edge—often at the top or the right.
• Use a protractor to measure the angle for each gas composition, starting from your initial point and measuring clockwise direction.
• Draw each segment by aligning the protractor correctly with the circle’s center, marking the endpoint of each angle measure.
• Once all sections are marked, connect them back to the circle's center to complete the partitioning.
• Label each segment appropriately with both the percentage and the gas name (e.g., "Nitrogen 78.08%"), making it easy to interpret the graph.

This pie chart graphically represents the atmospheric composition proportions and can be a powerful tool in data analysis and presentations.

Visual Representation in Chemistry

Visual aids like circle graphs are incredibly useful for interpreting and understanding chemical data. In chemistry, the composition of gases, liquids, or compounds can be effectively conveyed using such graphs.
The process of turning quantitative chemical data into visual formats helps in memorizing and relating concepts. For example, understanding the air composition through a circle graph allows us to

• quickly gauge the major and minor components of the atmosphere,
• engage with the data more intuitively than with numbers alone,
• identify variations easily, which could indicate environmental changes or pollution levels.

Visual representation is not just educational but also enhances cognitive processing, making chemistry more accessible and engaging to learn.