Physical Science Module 2

Explanation
Humidity refers to the amount of moisture or water vapor present in the air. It is a measure of the air's ability to hold water vapor, and it affects the comfort level and perceived temperature. Humidity can be influenced by factors such as evaporation, sweating, and the greenhouse effect, which traps heat and increases the moisture content in the air. Therefore, humidity is the correct answer as it directly relates to the moisture content of the air.

Explanation
Absolute humidity refers to the mass of water vapor present in a given volume of air. It is a measure of the actual amount of water vapor in the air, regardless of the air's temperature. Relative humidity, on the other hand, is the ratio of the amount of water vapor present in the air to the maximum amount the air could hold at a given temperature. Saturated refers to a condition where the air is holding the maximum amount of water vapor it can at a particular temperature. Heat index, on the other hand, is a measure of how hot it feels when relative humidity is combined with the actual air temperature.

Explanation
Relative humidity is the correct answer because it is the ratio of the mass of water vapor in the air at a given temperature to the maximum mass of water vapor the air could hold at that temperature, expressed as a percentage. Relative humidity is an important measure of the amount of moisture in the air and is used to understand and predict weather conditions.

Explanation
The process by which certain gases trap heat that radiates from the earth is known as the greenhouse effect. This effect occurs when greenhouse gases, such as carbon dioxide and methane, absorb and re-emit infrared radiation, preventing it from escaping into space. This trapped heat leads to an increase in the Earth's temperature, causing global warming and climate change.

Explanation
The statement is false because ethanol is not a gas responsible for trapping heat that radiates from Earth. The correct gases responsible for this are water vapor, carbon dioxide, and methane. Ethanol is not a greenhouse gas and does not contribute significantly to the greenhouse effect.

Explanation
Water evaporates more slowly under conditions of high humidity because the air is already saturated with water vapor. When the humidity is high, the air contains a lot of moisture, which reduces the rate of evaporation. This is because there is less room for additional water molecules to escape from the liquid phase into the gas phase. In contrast, low humidity means that the air is dry and has a lower concentration of water vapor, allowing for faster evaporation. High temperatures can also increase the rate of evaporation, but in this case, the presence of high humidity counteracts the effect of temperature. Windy conditions can enhance evaporation by removing the water vapor near the liquid surface, but high humidity can still slow down the process.

Explanation
The majority of the gas we inhale is nitrogen. Oxygen is also present in the air we breathe, but it makes up a smaller percentage compared to nitrogen. Carbon dioxide is produced as a waste product in our bodies and is exhaled, while argon is a noble gas that is present in very small amounts in the atmosphere. Therefore, the correct answer is nitrogen.

Explanation
Ozone serves the purpose of blocking ultraviolet light from the sun. Ozone molecules in the Earth's atmosphere act as a protective layer that absorbs and filters out harmful UV radiation, preventing it from reaching the surface. This helps to protect living organisms from the damaging effects of excessive UV exposure, such as skin cancer, cataracts, and damage to marine ecosystems.

Explanation
Decreasing the concentration of ground level ozone in the air is beneficial for good health. Ground level ozone is a harmful pollutant that can cause respiratory issues, such as coughing, chest tightness, and shortness of breath. It can also worsen existing conditions like asthma and bronchitis. By decreasing the concentration of ground level ozone, we can reduce the risk of these health problems and improve overall air quality. Therefore, decreasing the concentration of ground level ozone is the correct answer for good health.

Explanation
The statement suggests that the average temperature of the earth has increased significantly in the past 80 years. However, the correct answer is False. This implies that the average temperature of the earth has not increased significantly in the past 80 years.

Explanation
To convert a percentage to parts per million (ppm), we multiply the percentage by 10,000. In this case, 1% is equivalent to 1 * 10,000 = 10,000 ppm.

Explanation
The mandate of catalytic converters decreased the concentration of carbon monoxide. Catalytic converters are designed to convert harmful pollutants, such as carbon monoxide, into less harmful substances before they are released into the atmosphere. By implementing catalytic converters in vehicles, the emission of carbon monoxide is reduced, leading to improved air quality and a decrease in the concentration of this pollutant.

Explanation
When the oxygen level increases, the rate at which a certain substance burns will also increase. This is because oxygen is necessary for combustion to occur. When there is more oxygen available, it allows for a greater amount of fuel to be oxidized, resulting in a faster and more intense burning process. Therefore, the statement is true.