Nursing Elites

1. Which of the following is unique to covalent bonds?

• A. Most covalent bonds are formed between the elements H, F, N, and O.
• B. Covalent bonds are dependent on forming dipoles.
• C. Bonding electrons are shared between two or more atoms.
• D. Molecules with covalent bonds tend to have a crystalline solid structure.

Correct answer: C

Rationale: The correct answer is C: 'Bonding electrons are shared between two or more atoms.' This statement is unique to covalent bonds. In covalent bonds, atoms share electrons to achieve a stable electron configuration, which leads to the formation of a bond. This sharing of electrons is a fundamental characteristic of covalent bonds and distinguishes them from other types of chemical bonds, such as ionic bonds, where electrons are transferred rather than shared. Choices A, B, and D do not represent unique characteristics of covalent bonds. Choice A describes some common elements involved in covalent bonds, choice B refers to the concept of dipoles, which can also exist in other types of bonds, and choice D describes a property of molecules (crystalline solid structure) that is not exclusive to covalent bonds.

2. Which term describes the resistance of a substance to flow?

• A. Density
• B. Viscosity
• C. Conductivity
• D. Malleability

Correct answer: B

Rationale: Viscosity is the term used to describe the resistance of a substance to flow. It quantifies how thick or thin a fluid is and how easily it flows. Density (A) refers to the mass of a substance per unit volume and does not directly relate to resistance to flow. Conductivity (C) is the property of a material to conduct electricity or heat, not related to resistance to flow. Malleability (D) is the property of a material to be hammered or rolled into thin sheets, which is not related to resistance to flow.

3. What happens to the momentum of an object when there is no external force acting upon it?

• A. Momentum increases
• B. Momentum decreases
• C. Momentum remains constant
• D. Momentum becomes zero

Correct answer: C

Rationale: When there is no external force acting upon an object, the law of conservation of momentum dictates that the momentum of the object remains constant. This means that the momentum does not increase or decrease; it stays the same. Choice A is incorrect because momentum does not increase. Choice B is incorrect because momentum does not decrease. Choice D is incorrect as momentum does not become zero; it remains constant as per the conservation law. Therefore, the correct answer is C, as the object's momentum is unchanged in the absence of external forces.

4. What is the tough, fibrous tissue that connects bones at joints called?

• A. Cartilage
• B. Ligaments
• C. Tendons
• D. Fascia

Correct answer: B

Rationale: Ligaments are the tough, fibrous tissue that connects bones at joints, providing stability and support to prevent excessive movement and potential injury. Cartilage is a smooth, rubbery connective tissue that covers bone ends at joints. Tendons connect muscles to bones, enabling movement. Fascia surrounds muscles, blood vessels, and nerves, providing support and structure to these tissues. In this context, ligaments are specifically the connective tissues that bind bones together at joints, not cartilage, tendons, or fascia.

5. What is the main function of the large intestine?

• A. To absorb proteins
• B. To absorb water and form feces
• C. To produce enzymes for digestion
• D. To store fat

Correct answer: B

Rationale: The main function of the large intestine is to absorb water and form feces from waste material. Choice A is incorrect because the absorption of proteins primarily occurs in the small intestine. Choice C is incorrect as the production of enzymes for digestion mainly takes place in the pancreas and small intestine. Choice D is incorrect as the storage of fat is not a primary function of the large intestine.

Similar Questions