Nursing Elites

1. In the periodic table, which group contains the alkali metals?

• A. Group 7
• B. Group 1
• C. Group 2
• D. Group 3

Correct answer: B

Rationale: The correct answer is Group 1. Alkali metals are found in Group 1 of the periodic table, which includes elements such as lithium, sodium, and potassium. These elements are known for their high reactivity and tendency to form alkaline solutions when they react with water. Therefore, Group 1 is specifically designated as the group containing alkali metals. Choice A (Group 7) is incorrect as Group 7 contains the halogens. Choice C (Group 2) is incorrect as Group 2 contains the alkaline earth metals. Choice D (Group 3) is incorrect as Group 3 contains the scandium group of elements.

2. What is the name of the negatively charged subatomic particles?

• A. Protons
• B. Neutrons
• C. Electrons
• D. Isotopes

Correct answer: C

Rationale: The correct answer is C: Electrons. Electrons are the negatively charged subatomic particles. They are found outside the atomic nucleus and carry a negative charge. Protons are positively charged particles found in the nucleus, neutrons have no charge, and isotopes are atoms of the same element with different numbers of neutrons, not subatomic particles.

3. What is the oxidation state of the nitrogen atom in the compound NH3?

• A. -3
• B. -1
• C. +1
• D. +3

Correct answer: B

Rationale: In the compound NH3, nitrogen is bonded to three hydrogen atoms. Hydrogen is always assigned an oxidation state of +1. Since the overall charge of NH3 is zero, the oxidation state of nitrogen must be -1 to balance out the hydrogen's +1 oxidation state. Therefore, the correct oxidation state of the nitrogen atom in NH3 is -1. Choice A (-3) is incorrect because it does not account for the electronegativity of hydrogen. Choice C (+1) and Choice D (+3) are incorrect as the nitrogen atom in NH3 needs to balance the +1 oxidation state of each hydrogen atom, resulting in a total of -3 to maintain the compound's charge neutrality.

4. What happens in a single displacement reaction?

• A. A compound decomposes into two substances.
• B. An active element displaces a less active element.
• C. A precipitate solid forms from the reaction of two solutions.
• D. The oxidation states of atoms in the reactants change.

Correct answer: B

Rationale: In a single displacement reaction, an active element displaces a less active element in a compound. This process involves one element replacing another in a compound, resulting in the formation of a new compound. Option A is incorrect because a single displacement reaction does not involve the decomposition of a compound into two substances. Option C is incorrect because it describes a precipitation reaction, not a single displacement reaction. Option D is incorrect because it describes oxidation-reduction reactions, not specifically single displacement reactions.

5. Which of the following is a characteristic of a chemical change?

• A. Change in shape
• B. Production of gas
• C. Melting
• D. Freezing

Correct answer: B

Rationale: The production of gas is a characteristic of a chemical change. During a chemical change, new substances are formed, often with the release or absorption of energy. The production of gas is a significant indicator of a chemical change because it indicates the formation of new compounds through chemical reactions. Choices A, C, and D are not characteristics of chemical changes. Changes in shape, melting, and freezing are physical changes where the substance's identity remains the same, unlike in chemical changes where new substances with different properties are formed.

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