Nursing Elites

1. When balanced, the reaction Fe + O₂ → FeO will be?

• A. 2Fe + 2Oâ‚‚ → 3FeO
• B. 4Fe + 6Oâ‚‚ → 6FeO
• C. 2Fe + 3Oâ‚‚ → 2FeO
• D. 4Fe + 3Oâ‚‚ → 2FeO

Correct answer: C

Rationale: To balance the chemical equation Fe + O₂ → FeO, the coefficients needed are 2 for Fe and 1 for O. Therefore, the balanced equation becomes 2Fe + O₂ → 2FeO, which translates into 2Fe + 3O₂ → 2FeO. This corresponds to option C. Choice A has the incorrect number of oxygen molecules. Choice B has an incorrect number of Fe atoms on the product side. Choice D also has an incorrect number of Fe atoms on the product side.

2. What charge do Group IA elements have?

• A. +1
• B. +2
• C. +3
• D. 0

Correct answer: A

Rationale: Group IA elements, also known as alkali metals, have a +1 charge. They readily lose one electron to achieve a stable electron configuration, forming ions with a single positive charge. This makes +1 the correct choice. Choices B, C, and D are incorrect because alkali metals in Group IA typically lose one electron, so they do not have a +2, +3, or 0 charge.

3. At what temperature does water boil in °F?

• A. 210°F
• B. 212°F
• C. 215°F
• D. 220°F

Correct answer: B

Rationale: Water boils at 212°F under standard atmospheric pressure. This is the point at which water changes from a liquid to a gas phase. Choice A (210°F) is incorrect as it is below the boiling point of water. Choice C (215°F) and Choice D (220°F) are also incorrect as they are above the boiling point of water.

4. Which element is considered a noble gas?

• A. Oxygen
• B. Neon
• C. Hydrogen
• D. Argon

Correct answer: B

Rationale: The correct answer is 'Neon.' Noble gases are a group of elements with very low reactivity. Neon is one of these elements, known for its stable and unreactive nature. Oxygen, hydrogen, and argon do not belong to the noble gas group. Oxygen is a reactive non-metal, hydrogen is a non-metal and the first element in the periodic table, and argon is a noble gas like neon but not the correct answer in this case.

5. How many amino acids are essential for human life?

• A. 22
• B. 20
• C. 18
• D. 24

Correct answer: B

Rationale: There are 20 essential amino acids required for human life. These amino acids cannot be synthesized by the body and must be obtained through the diet. They play crucial roles in various physiological functions and are necessary for protein synthesis and overall health. Choice A is incorrect because there are not 22 essential amino acids. Choice C is incorrect as there are more than 18 essential amino acids. Choice D is incorrect as there are not 24 essential amino acids for human life.

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