Question 1:

A water molecule (H₂O) is formed when one oxygen atom shares electrons with two hydrogen atoms. This type of bond, where atoms share electrons, is called a covalent bond. In a water molecule, the oxygen and hydrogen atoms are held together by these shared electron pairs. The sharing is unequal, making water a polar molecule, but the bonds themselves are covalent, not ionic.

The correct answer is D. covalent bonds between two hydrogen atoms and one oxygen atom.

*These A.I. responses may be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 2:

The unequal sharing of electrons in a water molecule results in polar covalent bonds. Since the oxygen nucleus is more attractive to electrons, it pulls the shared electrons closer to it. This creates a region of slight negative charge around the oxygen atom. As a result, the hydrogen atoms, which have had their shared electrons pulled away, become slightly positive. The resulting water molecule has a net negative charge on the oxygen side and a net positive charge on the hydrogen side, making it a polar molecule.

The correct answer is B. Partial positive charge on Hydrogen, and Partial negative charge on Oxygen.

*These A.I. responses may be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 3:

Substances that dissolve in water are known as hydrophilic (from the Greek words hydro, meaning "water," and philos, meaning "loving"). These substances are typically polar or ionic, which allows them to form strong attractions with the polar water molecules, leading to them dissolving.

The correct answer is C. hydrophilic.

A. Hydrophobic: This term describes substances that do not mix with or dissolve in water ("water-fearing"). Examples include oil and fat.

B. Insoluble: This is a general term for a substance that does not dissolve in a solvent. While related, "hydrophobic" is a more specific term for substances that don't dissolve in water.

D. Hydrolysing: This refers to the chemical reaction of hydrolysis, where a molecule is broken down by the addition of water, not the physical property of dissolving.

*These A.I. responses may be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 4:

A triglyceride is a type of lipid (fat or oil) composed of a glycerol molecule and three fatty acid chains. The long hydrocarbon chains of the fatty acids are nonpolar, which means they do not have partial positive and negative charges like water molecules. Because of this, they are unable to form hydrogen bonds with water, making the entire molecule hydrophobic ("water-fearing").

The correct answer is A. Triglyceride.

Glucose and ribose are both sugars (carbohydrates). Their molecular structures contain many hydroxyl (−OH) groups, which are polar and can form hydrogen bonds with water. This makes them hydrophilic ("water-loving") and easily soluble in water.

DNA is a large molecule with a sugar-phosphate backbone and nitrogenous bases. The phosphate groups in the backbone are negatively charged, making them highly polar and hydrophilic. While the nitrogenous bases in the interior of the double helix are nonpolar, the overall molecule is soluble in water due to its polar backbone.

*These A.I. responses may be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 5:

Capillary action is a phenomenon that relies on two primary properties of water: adhesion and cohesion.

Adhesion is the attraction between water molecules and other surfaces (like the walls of a plant's xylem vessels or the particles of soil).

The correct answer is C. Adhesion.

Cohesion is the attraction between water molecules themselves, which holds the column of water together.

In capillary action, the adhesive forces cause the water molecules to "climb" up the sides of a narrow tube or pore, while the cohesive forces pull the other water molecules up with them, against the force of gravity. This combined action is what moves water up plant stems and through the soil.

*These A.I. responses may be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 6:

The transport of water up the xylem in plants is explained by the cohesion-tension theory. This theory is based on the unique properties of water, specifically its ability to stick to itself (cohesion) and to other surfaces (adhesion).

The correct answer is A. Cohesion.

Here's how it works:

• Transpiration: Water evaporates from the leaves through small pores called stomata.
• Tension: This evaporation creates a negative pressure, or "pull," at the top of the plant.
• Cohesion: Because of cohesion, each water molecule pulls on the one behind it, creating a continuous column of water that extends all the way from the leaves down to the roots.
• Adhesion: The water column is also held in place by adhesion, as the water molecules stick to the walls of the xylem vessels, helping to counteract gravity.

*These A.I. responses may be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 7:

Cohesion is the attractive force between water molecules themselves.
This force is a result of hydrogen bonds, which form between the partially positive hydrogen atom of one water molecule and the partially negative oxygen atom of an adjacent water molecule. This property allows water molecules to stick together and is a key reason for phenomena like surface tension and the transport of water in plants.

The correct answer is C. The hydrogen bonding between hydrogen and oxygen in a different water molecule.

*These A.I. responses may be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 8:

I. Water produces more buoyancy than air

This is correct. Because water is much denser than air, it produces a stronger upward buoyant force on the loon's body. To counteract this force and be able to sink and swim underwater, the loon needs adaptations like solid bones (which make it denser than other flying birds) and the ability to compress air from its lungs and feathers to decrease its overall volume and buoyancy.

II. Water is less viscous than air

This is incorrect. Water is more viscous than air. Viscosity is a fluid's resistance to flow. The loon's streamlined body shape is an adaptation to reduce this viscous drag, but the viscosity of water is not the reason it needs to be dense enough to sink.

III. Water is a better thermal conductor than air

This is correct, but it is not the reason the loon needs to have adaptations to sink. Thermal conductivity relates to heat loss, not buoyancy. A loon's dense feathers and fat layers are adaptations to reduce heat loss in water, but this is a different physical challenge from overcoming buoyancy.

The correct answer is A. I only.

This statement is the only one that directly relates to the necessity of a bird having solid bones or compressing air to overcome buoyancy when diving.

*These A.I. responses may be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 9:

The correct answer is D. maintain a relatively stable temperature.

Water has a very high specific heat capacity, which means it takes a large amount of energy to change its temperature.

*These A.I. responses may be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 10:

The statement that water is a "universal solvent" is a common phrase used to describe its remarkable dissolving power. However, it's technically inaccurate because water cannot dissolve everything. The reason it's so good at dissolving substances is due to its polarity.

Water molecules have a partial positive charge on the hydrogen side and a partial negative charge on the oxygen side, which allows them to attract and pull apart ionic compounds (like salt) and other polar molecules (like sugar).

However, water is unable to dissolve non-polar substances, such as oils, fats, and other lipids, because these molecules lack the charges that water needs to interact with them. The phrase "like dissolves like" is key here: polar solvents dissolve polar solutes, and non-polar solvents dissolve non-polar solutes. Since water is polar, it cannot dissolve non-polar substances.

The correct answer is C. Water does not dissolve organic compounds such as lipids.

*These A.I. responses may be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.