Nursing Elites

1. What charge do Group VIIA elements have?

• A. -1
• B. -2
• C. 0
• D. 1

Correct answer: A

Rationale: Group VIIA elements, also known as halogens, have a tendency to gain one electron to achieve a stable electron configuration, resulting in a -1 charge. This is because they have seven valence electrons and need one more to complete their octet, making them highly reactive in forming -1 ions. Therefore, the correct answer is A. Choice B (-2) is incorrect because Group VIIA elements typically gain one electron, not two. Choice C (0) is incorrect as these elements tend to form -1 ions by gaining one electron. Choice D (1) is incorrect because Group VIIA elements gain electrons to form negative ions, not positive ones.

2. What are bases or alkaline solutions known as?

• A. Hydrogen acceptors
• B. Solutions of low pH
• C. Hydrogen donors
• D. Amphoteric

Correct answer: A

Rationale: Bases or alkaline solutions are known as 'hydrogen acceptors.' They accept protons (H+) in chemical reactions, as opposed to acids that donate protons. This property allows bases to neutralize acids and form salts. Choice B, 'Solutions of low pH,' is incorrect because bases have high pH values, not low. Choice C, 'Hydrogen donors,' is incorrect as bases do not donate protons but accept them. Choice D, 'Amphoteric,' refers to substances that can act as both acids and bases, which is not the definition of bases. Therefore, the correct answer is A.

3. To the nearest whole number, what is the mass of one mole of water?

• A. 16 g/mol
• B. 18 g/mol
• C. 20 g/mol
• D. 22 g/mol

Correct answer: B

Rationale: The molar mass of water (Hâ‚‚O) is calculated by adding the atomic masses of two hydrogen atoms (each with a molar mass of approximately 1 g/mol) and one oxygen atom (with a molar mass of approximately 16 g/mol). Therefore, the molar mass of water is approximately 18 g/mol, making choice B the correct answer. Choice A (16 g/mol) is incorrect because it represents the molar mass of oxygen, not water. Choices C (20 g/mol) and D (22 g/mol) are incorrect as they do not correspond to the molar mass of water.

4. Which type of change occurs when no change is made to the chemical composition of a substance?

• A. Chemical
• B. Physical
• C. Nuclear
• D. Mechanical

Correct answer: B

Rationale: A physical change refers to alterations in the state of matter without modifying the chemical composition of the substance. Examples of physical changes include changes in state (solid, liquid, gas), shape, size, or phase. In a physical change, the substance may look different or behave differently, but its chemical structure remains the same. On the other hand, chemical changes involve the breaking and forming of chemical bonds, resulting in the creation of entirely new substances with different chemical properties. Nuclear changes involve alterations in the nucleus of an atom, such as radioactive decay. Mechanical changes refer to changes in the position or motion of an object caused by applied forces, like pushing, pulling, or twisting.

5. In the solid state, you would expect a nonmetal to be _________.

• A. brittle
• B. lustrous
• C. malleable
• D. conductive

Correct answer: A

Rationale: In the solid state, you would expect a nonmetal to be brittle. Nonmetals generally lack the malleability and ductility of metals, which makes them prone to being brittle and easily fractured under stress. This property is due to the lack of metallic bonding in nonmetals, which results in a more rigid and less flexible structure. Choice B, 'lustrous,' is incorrect because nonmetals typically do not exhibit a shiny or reflective surface like metals do. Choice C, 'malleable,' is also incorrect as nonmetals lack the ability to be hammered or rolled into thin sheets like metals. Choice D, 'conductive,' is incorrect since nonmetals are generally poor conductors of electricity compared to metals.

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