Physical Science Module 5

The explanation for the given correct answer is that the concentration of salt in the oceans has been increasing gradually over time due to various geological and chemical processes. If the earth was billions of years old, the oceans would have accumulated much more salt, making them significantly saltier than they are today. However, the current salinity levels in the oceans align with the estimated age of the earth, which is in the range of a few billion years. Therefore, this supports the statement that the earth cannot be billions of years old based on the salinity of the oceans.

Residence time refers to the average amount of time that a particle or substance remains in a given system. It is a measure of how long a particle stays within a specific environment or process. This term is commonly used in various fields such as environmental science, chemistry, and engineering to understand the behavior and movement of particles within a system. The other options, such as evaporation time, atmospheric time, and tea time, do not accurately describe the concept of the average time a particle stays in a system.

Groundwater is the largest source of liquid freshwater on the planet because it is stored beneath the Earth's surface in aquifers. These aquifers contain vast amounts of water that have accumulated over time from rainfall and other sources. Groundwater is continuously replenished through the process of infiltration and provides a reliable supply of freshwater for drinking, agriculture, and other human needs. Unlike rivers, lakes, and ponds, which are visible bodies of water and can be affected by factors like evaporation and seasonal changes, groundwater remains relatively stable and accessible throughout the year.

Transpiration is the correct answer because it refers to the process of water evaporation from plants. During transpiration, water is absorbed by the roots of the plant and then transported to the leaves, where it evaporates through small pores called stomata. This process helps plants regulate their temperature and also allows for the movement of water and nutrients throughout the plant.

Adiabatic cooling refers to the process in which a gas cools down as it expands without any heat exchange with its surroundings. This occurs because the expanding gas performs work on its surroundings, causing a decrease in its internal energy and hence a decrease in temperature. Unlike diabatic cooling, which involves heat exchange, adiabatic cooling occurs in an isolated system where no additional energy is added or removed. Sporatic cooling and expanded cooling are not recognized terms in the context of gas expansion and cooling.

The majority of Earth's water resides in the oceans. Oceans cover about 71% of the Earth's surface and hold approximately 97% of the planet's water. This is because water from rivers, precipitation, and other sources eventually flows into the oceans. Oceans play a crucial role in regulating the Earth's climate, storing heat, and supporting diverse marine ecosystems.

Icebergs form from freshwater and come from glaciers. Glaciers are made up of compacted snow and ice, which in turn is formed from freshwater precipitation. Over time, the weight of the snow and ice causes it to compress and form glaciers. When chunks of ice break off from glaciers, they float in the ocean as icebergs. Since glaciers are formed from freshwater sources, it follows that icebergs are also composed of freshwater.

The residence time is longer in the ocean compared to a fast-moving stream. This is because the ocean is a large body of water with a slower flow rate, allowing water to circulate and stay within the ocean for a longer period. In contrast, a fast-moving stream has a higher flow rate, causing water to move quickly and have a shorter residence time before it is carried downstream.

Condensation is the correct answer because it refers to the process in which a gas changes into a liquid state. This occurs when the gas loses heat energy and its particles come closer together, forming liquid droplets. Condensation is a crucial part of the water cycle, where water vapor in the atmosphere cools down and transforms into liquid water, leading to the formation of clouds, fog, or dew. Respiration and transpiration are related to biological processes, while precipitation refers to the falling of liquid or solid water from the atmosphere.

If a lake has no means of getting rid of water except evaporation, it will contain saltwater. This is because when water evaporates, it leaves behind any dissolved salts, minerals, or impurities, resulting in an increase in salinity. Over time, the concentration of salt in the lake will continue to increase, making it a saltwater lake.

Percolation refers to the process of water moving downwards through the soil towards the water table. This movement occurs due to gravity and the porous nature of the soil, allowing water to pass through the gaps between particles. It is an essential process for the replenishment of groundwater and the formation of underground aquifers. Transpiration, on the other hand, is the process by which plants release water vapor through their leaves. Soil moisture refers to the amount of water present in the soil, while soaking simply refers to the act of saturating something with water.

Groundwater pollution is not easy to trace back to its original source. This is because groundwater moves through porous materials and can travel long distances, making it difficult to pinpoint the exact location of pollution sources. Additionally, the process of contaminant transport through groundwater can be complex, involving various factors such as the type of pollutant, the geology of the area, and the flow characteristics of the groundwater system. Therefore, it is often challenging to determine the exact source of groundwater pollution.

Precipitation is the correct answer because glaciers are formed when snow accumulates over time and undergoes compaction and recrystallization. This process is known as "precipitation" and it occurs when water vapor in the atmosphere condenses into ice crystals or snowflakes and falls to the ground. Over time, with more snowfall and the weight of the accumulated snow, the lower layers are compressed into ice, forming glaciers.

After going through transpiration, a molecule of water is released into the atmosphere. Transpiration is the process by which water is evaporated from plants through their leaves. This water vapor then enters the atmosphere, where it can condense and form clouds or participate in other atmospheric processes. Therefore, the correct answer is "Atmosphere."

When a sample of gas is compressed, the volume of the gas decreases. According to Boyle's Law, when the volume of a gas decreases, the pressure increases. This increase in pressure causes an increase in the kinetic energy of the gas particles, resulting in an increase in temperature. Therefore, when a gas is compressed and no other changes are allowed, the temperature of the gas will increase.

Evaporation is the process by which water changes from a liquid to a gas, and in this case, it occurred in the ocean. The water vapor then rises into the atmosphere and undergoes condensation, which is the process of water vapor turning back into liquid water. This condensation forms clouds, and eventually, the water droplets in the clouds combine to form precipitation, which can fall back to the Earth's surface as rain, snow, or other forms of precipitation. Therefore, the transfer of water from the ocean to a cloud involves the processes of evaporation and condensation.

Freezing ocean water in the polar region does not directly form an iceberg. Icebergs are formed when large chunks of ice break off from glaciers or ice shelves and float in the ocean. While freezing ocean water contributes to the formation of sea ice, which is different from icebergs, it does not directly result in the creation of icebergs.

Adiabatic cooling is the correct answer because it refers to the cooling of air as it rises and expands in the atmosphere. When moist air rises, it expands due to lower atmospheric pressure, causing a decrease in temperature. This cooling process is adiabatic because it occurs without any exchange of heat with the surroundings. As the air cools, it reaches its dew point and condensation occurs, forming clouds. Therefore, adiabatic cooling is the main factor that leads to the temperature change necessary for condensation and cloud formation.

When there is a lot more rain than normal in an area over an extensive length of time, the excess water will infiltrate into the ground and percolate through the soil layers. This will cause the water table to rise, resulting in a decrease in its depth.