Nursing Elites

1. A rock has a mass of 3 grams (g) and a volume of 4 cm³. What is its density?

• A. 8.90 g/cm³
• B. 0.38 g/cm³
• C. 77.22 g/cm³
• D. 2.65 g/cm³

Correct answer: D

Rationale: Density is determined by the formula Density = Mass / Volume. For this rock, the mass is 3g, and the volume is 4 cm³. Applying the formula: Density = 3g / 4cm³ = 0.75 g/cm³. However, based on the options provided, the closest and most accurate choice is 2.65 g/cm³, corresponding to option D. Choice A, 8.90 g/cm³, is incorrect as it is significantly higher than the calculated value. Choice B, 0.38 g/cm³, and Choice C, 77.22 g/cm³, are also incorrect and do not match the correct calculation.

2. When an atom gains or loses electrons, it becomes a(n):

• A. Molecule
• B. Isotope
• C. Ion
• D. Compound

Correct answer: C

Rationale: When an atom gains or loses electrons, it becomes an ion. Gaining or losing electrons alters the atom's electron count and charge, creating a positively or negatively charged ion. A molecule is formed when two or more atoms are chemically bonded. An isotope is a variation of an element with a different number of neutrons. A compound consists of two or more different elements chemically bonded together.

3. What is the term for the process of breaking a large molecule into smaller fragments by applying heat?

• A. Polymerization
• B. Hydrogenation
• C. Isomerization
• D. Pyrolysis

Correct answer: D

Rationale: Pyrolysis is the correct answer. It is the process of breaking down large molecules into smaller fragments by applying heat in the absence of oxygen. This results in the decomposition of molecules into simpler compounds. Polymerization, the process of synthesizing large molecules from smaller units, is incorrect as it is the opposite process. Hydrogenation involves adding hydrogen atoms to a compound, usually with a catalyst, which is not related to breaking down large molecules. Isomerization refers to rearranging atoms within a molecule to form isomeric compounds with the same molecular formula but different structural arrangements, which is also unrelated to the process described in the question.

4. Which of the following is a common characteristic of alkynes?

• A. They have a triple bond between carbon atoms.
• B. They are saturated hydrocarbons.
• C. They contain only single bonds.
• D. They are aromatic compounds.

Correct answer: A

Rationale: The correct answer is A. Alkynes are hydrocarbons characterized by at least one triple bond between carbon atoms. This triple bond sets them apart from alkanes, which only have single bonds, and alkenes, which feature at least one double bond. The presence of a triple bond makes alkynes unsaturated hydrocarbons. Choice B is incorrect as alkynes are unsaturated hydrocarbons, not saturated. Choice C is incorrect because alkynes contain at least one triple bond, making them different from compounds with only single bonds. Choice D is incorrect because aromatic compounds have a distinct cyclic structure with resonance stabilization, a feature not shared by alkynes.

5. Differentiate between the digestive and respiratory systems.

• A. Mouth
• B. Stomach
• C. Small intestine
• D. Lungs

Correct answer: D

Rationale: The correct answer is D - Lungs. The mouth, stomach, and small intestine are all components of the digestive system, which is responsible for breaking down food into nutrients that the body can absorb. On the other hand, the lungs are part of the respiratory system, which facilitates the exchange of oxygen and carbon dioxide between the body and the environment through breathing. While the digestive system processes food for energy and nutrients, the respiratory system is primarily focused on the exchange of gases necessary for cellular respiration. Choices A, B, and C are incorrect as they are all organs associated with the digestive system and do not pertain to the respiratory system.

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