1.
Adding salt to water causes the boiling point of water to be __________________. Higher/Lower
Explanation
Adding salt to water causes the boiling point of water to be higher. This is because when salt is added to water, it increases the boiling point of the solution. This occurs because the salt particles disrupt the formation of water vapor bubbles, which normally occurs during boiling. As a result, more heat is required to reach the boiling point, causing the boiling point to be higher than pure water.
2.
Adding salt to water causes the freezing point of water to be ______________________. Lower/ higher
Explanation
When salt is added to water, it disrupts the formation of ice crystals and reduces the freezing point of water. This happens because the salt particles interfere with the water molecules, making it more difficult for them to come together and form a solid structure. As a result, the freezing point of the water is lowered, and it requires lower temperatures for the water to freeze.
3.
Salts in the ocean _____________________ the pH of the ocean water.
Explanation
Salts in the ocean act as a buffer, meaning they help to stabilize and maintain the pH of the ocean water. Buffers are substances that resist changes in pH by accepting or donating hydrogen ions. In this case, the salts in the ocean can either release or absorb hydrogen ions, depending on the conditions, which helps to keep the pH of the water relatively constant. This buffering capacity is important for the survival of marine organisms, as sudden changes in pH can be harmful to their physiology and overall ecosystem.
4.
The _________________________ is the worlds largest aqueous solution.
Explanation
The ocean is the world's largest aqueous solution. It covers about 71% of the Earth's surface and contains a vast amount of dissolved salts and minerals. The term "ocean" is used to refer to the interconnected bodies of saltwater that cover the planet, including the Atlantic, Pacific, Indian, Arctic, and Southern oceans. These bodies of water are constantly in motion, driven by winds, tides, and currents, making them dynamic and essential for regulating the Earth's climate and supporting diverse marine ecosystems.
5.
_________________________________ is a measure of the dissolved salts in water.
Explanation
Salinity is a measure of the dissolved salts in water. It represents the concentration of salts, such as sodium, chloride, magnesium, and calcium, in a given body of water. Salinity is typically expressed as parts per thousand (ppt) or as a percentage. It is an important parameter in determining the quality and suitability of water for various purposes, including drinking, irrigation, and aquatic life. High salinity can have detrimental effects on plants, animals, and ecosystems, while low salinity can also pose challenges for certain organisms adapted to higher salt concentrations.
6.
Scientists calculate the salinity of sea water by usiing the following method/methods.
Correct Answer
E. Both A and B
Explanation
The correct answer is "Both A and B." Scientists calculate the salinity of sea water using both the conductivity of sea water and the evaporation method. Conductivity is a measure of how well a substance conducts electricity, and it is directly related to the salinity of the water. The evaporation method involves evaporating a sample of sea water and measuring the remaining salt content. Therefore, both methods are used to determine the salinity of sea water.
7.
The average salinity of sea water is __________ parts per thousand.
Correct Answer
B. 35
Explanation
Sea water has an average salinity of 35 parts per thousand. Salinity refers to the concentration of dissolved salts in water. The average salinity of sea water is determined by factors such as evaporation, precipitation, and the flow of freshwater from rivers into the ocean. A salinity of 35 parts per thousand means that for every 1,000 parts of water, there are 35 parts of dissolved salts. This level of salinity is essential for the survival of marine organisms and plays a crucial role in oceanic processes such as thermohaline circulation.
8.
What does psu stands for __________________________________________________.
Correct Answer
practical salinity units
Explanation
PSU stands for practical salinity units. This term is commonly used in oceanography to measure the salinity of seawater. Salinity refers to the concentration of dissolved salts in the water, and PSU provides a standardized unit of measurement for this. It is a practical and convenient way to express salinity levels, allowing scientists to compare and analyze data from different sources.
9.
The _______________________ lower/greater the psu the greater the salt content of the water being tested
Correct Answer
greater
Explanation
The answer "greater" is correct because the sentence states that the higher the psu (practical salinity unit), the higher the salt content of the water being tested. This implies that there is a direct relationship between the psu and salt content, where an increase in psu corresponds to an increase in salt content. Therefore, the greater the psu value, the greater the salt content of the water being tested.
10.
A __________________ ___________________ is a body of water with distinct properties based on where it originates.
Correct Answer
water mass
Explanation
A water mass is a body of water with distinct properties based on where it originates. This means that depending on its source, such as a specific ocean or river, a water mass will have unique characteristics such as temperature, salinity, and nutrient content. These distinct properties can affect the ecosystem and marine life within the water mass, making it an important concept in understanding and studying the Earth's oceans and bodies of water.
11.
The most common ion in sea water is
Correct Answer
C. Chloride
Explanation
Chloride is the most common ion in sea water because it is derived from the dissolution of salt deposits on the Earth's surface. The ocean's salinity is primarily due to the presence of chloride ions, which are abundant in seawater.
12.
More than ____________ elements are found in sea water.
Correct Answer
70
seventy
Explanation
The question asks for the number of elements found in sea water. The correct answer is "70" or "seventy" which indicates that there are a large number of elements present in sea water. This suggests that sea water is a complex mixture containing a diverse range of chemical elements.
13.
Common salt and _______________ are extracted from sea water.
Correct Answer
magnesium
Mg
Explanation
Common salt and magnesium are extracted from sea water. Magnesium is a mineral that is found in abundance in sea water and can be extracted through various processes. It is commonly used in industries for the production of alloys, as well as in agriculture as a fertilizer. The symbol for magnesium is Mg, derived from its Latin name "magnesium."