Nursing Elites

1. How does an unbalanced force affect an object at rest?

• A. It maintains the object's state of rest
• B. It does not affect the object's rest
• C. It moves the object into motion
• D. It decreases the object's mass

Correct answer: C

Rationale: An unbalanced force acting on an object at rest will cause the object to move into motion. This is in accordance with Newton's first law of motion, which states that an object at rest will remain at rest unless acted upon by an external force. Therefore, option C, 'It moves the object into motion,' is the correct answer. Choices A and B are incorrect because an unbalanced force disrupts the object's state of rest. Choice D is incorrect as force does not affect the mass of an object.

2. Which of the following is an example of a weak acid?

• A. Hydrochloric acid (HCl)
• B. Sulfuric acid (H2SO4)
• C. Acetic acid (CH3COOH)
• D. Nitric acid (HNO3)

Correct answer: C

Rationale: The correct answer is Acetic acid (CH3COOH) because it is a weak acid that only partially dissociates in water, resulting in a lower concentration of H+ ions compared to strong acids like hydrochloric acid (HCl), sulfuric acid (H2SO4), and nitric acid (HNO3) which completely dissociate in water. Weak acids do not fully ionize in water, leading to a lower concentration of H+ ions in solution. Hydrochloric acid, sulfuric acid, and nitric acid are strong acids that completely dissociate in water, producing a higher concentration of H+ ions. Therefore, they are not examples of weak acids.

3. Iron is a transition metal, which means it often forms a cation with a charge of what?

• A. 2- or 3-
• B. 1-
• C. 2+ or 3+
• D. 1+

Correct answer: C

Rationale: The correct answer is C: 2+ or 3+. Transition metals, like iron, are known for their ability to exhibit variable oxidation states. This characteristic allows them to form cations with charges such as 2+ or 3+. Specifically, iron can form cations with these charges due to the varying electron configurations in its d-orbitals. The other choices are incorrect because transition metals typically form positively charged cations, not negatively charged ones. Additionally, while iron can form cations with charges of 2+ or 3+, it does not commonly form cations with charges of 1- or 1+. Transition metal cations play a crucial role in forming coordination complexes with ligands, highlighting their importance in various chemical reactions.

4. What is the SI unit of measurement for acceleration?

• A. Meters per second (m/s)
• B. Newton (N)
• C. Meters (m)
• D. Meters per second squared (m/s²)

Correct answer: D

Rationale: The SI unit of measurement for acceleration is meters per second squared (m/s²). Acceleration is defined as the rate of change of velocity over time. It is a vector quantity with dimensions of length per time squared. Meters per second squared (m/s²) represents the change in velocity (meters per second) over a specific time interval (seconds) squared. Choice A, meters per second (m/s), represents velocity, not acceleration. Choice B, Newton (N), is the unit of force. Choice C, Meters (m), represents only distance, not acceleration. Therefore, the correct unit for acceleration is meters per second squared (m/s²).

5. Fluorescent microscopy utilizes which property of certain molecules to create a visible image?

• A. Staining properties
• B. Light absorption
• C. Fluorescence emission
• D. Refraction

Correct answer: C

Rationale: Fluorescent microscopy relies on the property of certain molecules to fluoresce when exposed to specific wavelengths of light. When these molecules absorb light energy, they become excited and then emit light at a longer wavelength, producing a visible image. This emitted light is what is used to create the image in fluorescent microscopy, making option C, fluorescence emission, the correct answer. Staining properties (option A) are used to enhance contrast in microscopy but are not the primary mechanism in fluorescent microscopy. Light absorption (option B) is involved in the excitation of fluorescent molecules but is not the property used to create the visible image. Refraction (option D) is the bending of light as it passes through different mediums and is not the property utilized in fluorescent microscopy.

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