Nursing Elites

1. If Silicon (Si) has an atomic mass of 28.1 AMU (atomic mass units), which of the following is the most likely number of neutrons an atom of Silicon would have?

• A. 28.1
• B. 14
• C. 28
• D. 14.2

Correct answer: B

Rationale: Silicon has an atomic number of 14, indicating it has 14 protons. The atomic mass of 28.1 AMU accounts for both protons and neutrons in the nucleus. By subtracting the atomic number from the atomic mass, we can estimate the number of neutrons in the atom. Thus, 28.1 - 14 = 14 neutrons. Choice A is incorrect as it represents the total atomic mass, not the number of neutrons. Choice C is incorrect; it is the atomic number (protons) rather than the number of neutrons. Choice D is incorrect as it is a value that does not reflect the number of neutrons in the silicon atom.

2. Convert 250 milliliters to liters.

• A. 25 liters
• B. 0.25 liters
• C. 2.5 liters
• D. 0.025 liters

Correct answer: B

Rationale: To convert milliliters to liters, you need to divide by 1000 since there are 1000 milliliters in a liter. Therefore, 250 milliliters is equal to 250/1000 = 0.25 liters. Choice A, 25 liters, is incorrect as it is a magnitude higher than the correct answer. Choice C, 2.5 liters, is also incorrect as it is 10 times greater than the correct conversion. Choice D, 0.025 liters, is incorrect as it is a magnitude lower than the correct conversion.

3. Which of the following statements is true regarding a supersaturated solution?

• A. It is unstable and tends to crystallize
• B. It contains more solute than it could dissolve
• C. It has a higher concentration than a saturated solution
• D. It is rarely encountered in everyday solutions

Correct answer: A

Rationale: A supersaturated solution is unstable and tends to crystallize because it contains more solute than it could dissolve at a given temperature. This excess solute is in a metastable state and can precipitate out if disturbed, leading to the formation of crystals. Option B is incorrect because a supersaturated solution does contain more solute than it could normally dissolve, but it becomes unstable due to this excess solute. Option C is incorrect because while a supersaturated solution does have a higher concentration than a saturated solution, the defining characteristic related to its instability is the excess solute. Option D is incorrect as supersaturated solutions can be encountered in various everyday scenarios, such as certain sugar solutions used in cooking or rock candy production.

4. What macromolecules are formed from amino acids, and what are their roles?

• A. Lipids; store energy
• B. Carbohydrates; provide energy
• C. Proteins; perform various functions like catalysis, transport, and structural support
• D. Nucleic acids; store genetic information

Correct answer: C

Rationale: The correct answer is C. Proteins are macromolecules formed from amino acids and have diverse roles, such as serving as enzymes, transport molecules, and providing structural support. They are essential for catalysis, cellular communication, immune response, and many other functions in living organisms. Choices A, B, and D are incorrect. Lipids are not formed from amino acids but from fatty acids and glycerol, mainly serving as energy storage molecules. Carbohydrates are composed of sugars and provide energy to the body. Nucleic acids, like DNA and RNA, are made up of nucleotides and store genetic information in cells.

5. Convert 2500 milliliters to liters.

• A. 2.5 liters
• B. 25 liters
• C. 0.25 liters
• D. 250 liters

Correct answer: A

Rationale: To convert milliliters to liters, you need to divide by 1000 since there are 1000 milliliters in a liter. Therefore, 2500 milliliters divided by 1000 equals 2.5 liters, making choice A the correct answer. Choice B is incorrect because it incorrectly multiplies instead of dividing. Choice C is incorrect as it incorrectly places the decimal point, resulting in an incorrect conversion. Choice D is incorrect as it multiplies instead of dividing, leading to an inaccurate conversion.

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