Nursing Elites

1. Which of the following substances can donate a hydroxide ion (OH-) in solution?

• A. Salt
• B. Base
• C. Neutral compound
• D. Dehydrating agent

Correct answer: B

Rationale: The correct answer is B: Base. A base is a substance that can donate hydroxide ions (OH-) in solution. Bases increase the concentration of hydroxide ions by either accepting protons (H+) or donating hydroxide ions. Salts are ionic compounds made of cations and anions, which do not directly donate hydroxide ions. Neutral compounds do not significantly affect the concentration of hydroxide ions. Dehydrating agents are substances that remove water molecules from other compounds, unrelated to donating hydroxide ions.

2. What is the momentum of a car with a mass of 1500 kg moving at a speed of 20 m/s?

• A. 30,000 kg m/s
• B. 1500 kg m/s
• C. 20 kg m/s
• D. Momentum cannot be determined without knowing the direction of motion.

Correct answer: A

Rationale: The momentum of an object is calculated by multiplying its mass by its velocity. In this case, the momentum of the car can be determined using the formula momentum = mass x velocity. Substituting the given values, momentum = 1500 kg x 20 m/s = 30,000 kg m/s. Therefore, the correct answer is A, 30,000 kg m/s. Choice B (1500 kg m/s) is incorrect because that value represents the mass of the car, not its momentum. Choice C (20 kg m/s) is incorrect as it only represents the speed of the car, not its momentum. Choice D (Momentum cannot be determined without knowing the direction of motion) is incorrect because momentum is a vector quantity and can be determined using magnitude and direction, but in this case, only the magnitude is required.

3. In which type of cell would you expect to find a high concentration of lysosomes?

• A. Cardiac cells
• B. Glandular cells
• C. Immune cells
• D. Neurons

Correct answer: C

Rationale: The correct answer is C: Immune cells. Immune cells, such as macrophages, contain many lysosomes for breaking down pathogens. Lysosomes are organelles responsible for digestion and waste removal within the cell, and immune cells require a high concentration of lysosomes to aid in their defense mechanisms against pathogens. Choice A, Cardiac cells, is incorrect because lysosomes are not primarily abundant in cardiac cells. Choice B, Glandular cells, is incorrect as well since lysosomes are not specifically concentrated in glandular cells. Choice D, Neurons, is also incorrect because while lysosomes are present in neurons, they are not typically found in high concentrations compared to immune cells.

4. What is the electrical charge of the nucleus?

• A. A nucleus always has a positive charge.
• B. A stable nucleus has a positive charge, but a radioactive nucleus may have no charge and instead be neutral.
• C. A nucleus always has no charge and is instead neutral.
• D. A stable nucleus has no charge and is instead neutral, but a radioactive nucleus may have a charge.

Correct answer: A

Rationale: A nucleus always has a positive charge. This is because the nucleus is composed of positively charged protons, along with neutral neutrons. The positive charge of the protons is balanced by the negative charge of the surrounding electrons in an atom, resulting in an overall neutral charge for the atom as a whole. Therefore, choice A is correct as it accurately reflects the positive charge of the nucleus due to the presence of protons. Choices B, C, and D are incorrect because they do not accurately represent the fundamental composition and charge distribution within an atom's nucleus. A stable nucleus consists of positively charged protons and neutral neutrons, leading to an overall positive charge, and not a neutral charge as suggested in the incorrect choices.

5. What is the difference between the atomic number and the mass number of an atom?

• A. The atomic number is the number of protons in the nucleus, while the mass number is the total number of protons and neutrons in the nucleus.
• B. The atomic number is the number of electrons in an atom, while the mass number is the total number of protons and neutrons in the nucleus.
• C. The atomic number is the number of neutrons in the nucleus, while the mass number is the total number of protons and electrons in an atom.
• D. The atomic number is the number of protons and neutrons in the nucleus, while the mass number is the total number of electrons in an atom.

Correct answer: A

Rationale: The atomic number of an atom represents the number of protons in its nucleus, which defines the element's identity. On the other hand, the mass number corresponds to the total sum of protons and neutrons in the nucleus. Therefore, the key distinction between the atomic number and the mass number lies in the fact that the atomic number specifically counts the protons, whereas the mass number encompasses both protons and neutrons. Choice B is incorrect because the atomic number is not related to the number of electrons but rather to the number of protons. Choice C is incorrect because the atomic number is not the number of neutrons but the number of protons. Choice D is incorrect because the atomic number does not include neutrons; it is solely the number of protons.

Similar Questions