Nursing Elites

1. On what concept is Kelvin based?

• A. Freezing point
• B. Absolute zero
• C. Boiling point
• D. Evaporation point

Correct answer: B

Rationale: The correct answer is B: Absolute zero. Kelvin is based on the concept of absolute zero, which is the point where molecular movement ceases entirely. This temperature scale starts at absolute zero (0K), where theoretically no molecular movement occurs. Choices A, C, and D are incorrect because Kelvin is not based on the freezing point, boiling point, or evaporation point, but rather on the absolute absence of molecular motion.

2. What type of radiation is high-energy electromagnetic radiation that lacks charge and mass?

• A. Beta
• B. Alpha
• C. Gamma
• D. Delta

Correct answer: C

Rationale: Gamma radiation is a form of high-energy electromagnetic radiation that does not possess charge or mass. This type of radiation is commonly used in various fields due to its penetrating ability and lack of charge or mass, making it different from alpha and beta radiation, which consist of charged particles. Therefore, the correct answer is C - Gamma. Choices A and B are incorrect as they refer to alpha and beta radiation, which are composed of charged particles. Choice D, Delta, is not a type of radiation.

3. How much concentrated HCl should be used to prepare 500 mL of a 0.100 M HCl solution?

• A. 75 mL
• B. 100 mL
• C. 125 mL
• D. 150 mL

Correct answer: B

Rationale: To prepare a 0.100 M HCl solution with a volume of 500 mL, you can use the formula C1V1 = C2V2, where C1 is the concentration of the concentrated HCl solution, V1 is the volume of concentrated HCl solution used, C2 is the desired concentration (0.100 M), and V2 is the final volume (500 mL). Rearranging the formula to solve for V1, you get V1 = (C2V2) / C1. Plugging in the values (0.100 M)(500 mL) / C1 = 100 mL, which means 100 mL of concentrated HCl should be used to prepare 500 mL of a 0.100 M HCl solution. Therefore, the correct answer is 100 mL. Choice A (75 mL), Choice C (125 mL), and Choice D (150 mL) are incorrect as they do not match the calculated volume needed to prepare the desired concentration of HCl solution.

4. What is the typical oxidation state of oxygen in most compounds?

• A. -1
• B. -2
• C. 0
• D. -3

Correct answer: B

Rationale: The correct answer is B: "-2". Oxygen usually exhibits an oxidation state of -2 in most compounds. This is due to oxygen's high electronegativity, which causes it to attract electrons, leading to the gain of two electrons in chemical reactions. Choice A (-1) is incorrect because oxygen rarely has an oxidation state of -1 in compounds. Choice C (0) is incorrect as oxygen does not usually have an oxidation state of zero in compounds. Choice D (-3) is incorrect as oxygen does not commonly have an oxidation state of -3 in compounds.

5. Which substance forms hydroxide ions when placed in water?

• A. Lemon juice
• B. Battery acid
• C. Vinegar
• D. Lye

Correct answer: D

Rationale: The correct answer is D, lye. Lye, also known as sodium hydroxide (NaOH), is a strong base that forms hydroxide ions (OH-) when placed in water. When lye dissolves in water, it dissociates into sodium ions (Na+) and hydroxide ions, making it an alkaline substance. Lemon juice, battery acid, and vinegar do not form hydroxide ions when placed in water. Lemon juice contains citric acid, battery acid contains sulfuric acid, and vinegar contains acetic acid, none of which produce hydroxide ions when dissolved in water.

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