Nursing Elites

1. What is the molarity of a solution made by dissolving 4.0 grams of NaCl into enough water to make 120 mL of solution? The atomic mass of Na is 23.0 g/mol, and Cl is 35.5 g/mol.

• A. 0.34 M
• B. 0.57 M
• C. 0.034 M
• D. 0.057 M

Correct answer: B

Rationale: To find the molarity, first calculate the moles of NaCl. Moles of NaCl = 4.0 g / (23.0 g/mol + 35.5 g/mol) = 0.068 mol. Next, use the formula for molarity: Molarity = moles of solute / liters of solution. Molarity = 0.068 mol / 0.120 L = 0.57 M. Therefore, the molarity of the solution is 0.57 M. Choice A, 0.34 M, is incorrect as it does not match the calculated molarity. Choice C, 0.034 M, is incorrect as it is a decimal point off from the correct molarity. Choice D, 0.057 M, is incorrect as it does not match the calculated molarity of 0.57 M.

2. What happens to the potential energy of an object as it falls freely near the Earth's surface?

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

Correct answer: A

Rationale: As an object falls freely near the Earth's surface, its potential energy decreases. This decrease occurs because the gravitational potential energy is being converted into kinetic energy as the object accelerates due to gravity. According to the law of conservation of energy, the total mechanical energy (the sum of potential and kinetic energy) remains constant in the absence of non-conservative forces like air resistance. Choice B ('Potential energy increases') is incorrect because the object's potential energy is being converted into kinetic energy, leading to a decrease. Choice C ('Potential energy remains constant') is incorrect as the conversion of potential energy to kinetic energy results in a decrease in potential energy. Choice D ('Potential energy becomes zero') is incorrect because potential energy is not reduced to zero but is transformed into kinetic energy as the object falls.

3. How does RNA polymerase differ from DNA polymerase?

• A. Both enzymes are identical in function and structure.
• B. RNA polymerase does not require a primer to initiate RNA synthesis.
• C. RNA polymerase can synthesize both RNA and DNA.
• D. RNA polymerase can only synthesize RNA, unlike DNA polymerase.

Correct answer: B

Rationale: Rationale: A) This statement is incorrect. RNA polymerase and DNA polymerase are not identical in function and structure. They have different roles in the cell. B) This statement is correct. Unlike DNA polymerase, RNA polymerase does not require a primer to initiate RNA synthesis. RNA polymerase can start the synthesis of RNA de novo. C) This statement is incorrect. RNA polymerase is specialized for synthesizing RNA, not DNA. DNA polymerase is responsible for synthesizing DNA. D) This statement is correct. RNA polymerase can only synthesize RNA, while DNA polymerase is responsible for synthesizing DNA.

4. Imagine you have an element with atomic number 11 and mass number 23. How many neutrons does it have?

• A. 11
• B. 12
• C. 23
• D. 21

Correct answer: B

Rationale: - The atomic number (Z) of an element is the number of protons in its nucleus. In this case, the element has an atomic number of 11. - The mass number (A) of an element is the sum of its protons and neutrons. Given that the mass number is 23 and the atomic number is 11, we can calculate the number of neutrons by subtracting the atomic number from the mass number: Neutrons = Mass number - Atomic number = 23 - 11 = 12. - Therefore, the element with atomic number 11 and mass number 23 has 12 neutrons.

5. Where does the electron transport chain occur in the cell?

• A. Cytosol
• B. Golgi apparatus
• C. Inner mitochondrial membrane
• D. Nucleus

Correct answer: C

Rationale: The electron transport chain occurs in the inner mitochondrial membrane. This process is crucial for the generation of ATP, the cell's energy currency. Choice A (Cytosol) is incorrect as the electron transport chain does not take place in the cytosol. Choice B (Golgi apparatus) is also incorrect as the Golgi apparatus is involved in modifying, sorting, and packaging of proteins. Choice D (Nucleus) is incorrect as the nucleus houses the cell's genetic material but is not the location of the electron transport chain.

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