Air: แบบฝึกหัด

A student uses a piece of dry blue cobalt chloride paper to test for a specific component of air. What is the substance being tested for, and what is the expected color change for a positive result?

Cigarette smoke contains carbon monoxide (\(CO\)). How does this specific component primarily interfere with the human body's gas exchange and transport system?

Which of the following gases is the third most abundant component in dry air, and what is its primary chemical property?

A healthy potted plant is sealed inside a transparent, air-tight glass container and placed under bright, continuous lighting for 24 hours. The initial composition of the air is normal atmospheric air. Assuming optimal temperature and water supply, which of the following statements correctly describes the net change in the plant's dry mass and the composition of the air inside the container after 24 hours?

Nitrogen gas constitutes a large portion of Earth's atmosphere. One of its crucial properties makes it widely used in applications such as food packaging (e.g., potato chips) and inert gas shielding for welding. What is this property?

Explain why a potted plant placed in a sealed, dark container will eventually die, even if it has sufficient water and nutrients.

In an experiment, a student notices that a burning splint is extinguished immediately when placed in a jar of nitrogen, but a glowing splint does not relight. Explain why these observations occur based on the properties of nitrogen and its role in the atmosphere.

State one physical property of nitrogen gas that makes it suitable for use in food packaging, and explain why this property helps preserve the quality of the food.

A student investigates the composition of air and the biological processes that maintain it. She sets up two identical airtight chambers, P and Q, each containing a small green plant and a container of limewater. Chamber P is placed in bright sunlight for 12 hours, while Chamber Q is kept in total darkness for the same duration.

(a) Describe the observable change in the limewater in Chamber Q after 12 hours and identify the gas responsible for this change. (2 points)

(b) In Chamber P, the limewater remains clear. However, if the student increases the number of small animals (like insects) inside Chamber P while keeping it in the sun, the limewater might eventually turn cloudy. Explain this observation by referencing the relative rates of two biological processes. (3 points)

(c) Explain how large-scale deforestation disrupts the natural constancy of the atmospheric oxygen level. (2 points)

The Earth's atmosphere maintains a delicate balance of gases, crucial for sustaining life. Two fundamental biological processes, photosynthesis and respiration, play key roles in regulating the concentrations of oxygen and carbon dioxide.

a) Explain how the processes of photosynthesis and respiration are interdependent and collectively maintain the natural balance of oxygen and carbon dioxide in the Earth's atmosphere. Include a word equation for each process.

b) Human activities significantly disrupt this natural balance, leading to global environmental concerns.

i) Name two major human activities that primarily lead to an increase in atmospheric carbon dioxide.

ii) Explain how the increased atmospheric carbon dioxide from these activities contributes to the 'greenhouse effect' and identify one observable environmental consequence of this effect.