Nursing Elites

1. What is matter that has a definite shape and volume?

• A. Liquid
• B. Solid
• C. Gas
• D. Plasma

Correct answer: B

Rationale: Matter that has a definite shape and volume is referred to as a solid. Solids maintain their shape and volume under normal conditions, unlike liquids that have a definite volume but take the shape of their container, gases that have neither a definite shape nor volume, and plasma which is a state of matter with no definite shape or volume and consists of charged particles.

2. If gas A has four times the molar mass of gas B, you would expect it to diffuse through a plug ___________.

• A. at half the rate of gas B
• B. at twice the rate of gas B
• C. at a quarter the rate of gas B
• D. at four times the rate of gas B

Correct answer: A

Rationale: When comparing the diffusion rates of two gases, according to Graham's law of diffusion, the rate of diffusion is inversely proportional to the square root of the molar mass. If gas A has four times the molar mass of gas B, the square root of the molar masses ratio (4:1) is 2. This means that gas A would diffuse through a plug at half the rate of gas B. Therefore, the correct answer is A, at half the rate of gas B. Choices B, C, and D are incorrect because they do not reflect the correct relationship between the molar masses and the rates of diffusion according to Graham's law.

3. What is the oxidation state of the sulfur atom in sulfuric acid H2SO4?

• A. 4
• B. 6
• C. 8
• D. 10

Correct answer: B

Rationale: In sulfuric acid (H2SO4), sulfur has an oxidation state of +6. The oxidation state is determined by considering the overall charge of the compound and the known oxidation states of other elements. In this case, hydrogen is typically +1, and oxygen is -2. To balance the charges and match the compound's overall charge of 0, sulfur must have an oxidation state of +6. Choice A (4) is incorrect because it doesn't balance the charges in the compound. Choices C (8) and D (10) are also incorrect as they are not valid oxidation states for sulfur in this compound.

4. What is a benefit of water's ability to make hydrogen bonds?

• A. Lack of cohesiveness
• B. Low surface tension
• C. Use as a nonpolar solvent
• D. High specific heat

Correct answer: D

Rationale: The correct answer is D, high specific heat. Water's ability to form hydrogen bonds results in a high specific heat capacity, allowing it to absorb and release a large amount of heat energy with minimal temperature change. This property is essential for moderating temperature changes in organisms and maintaining stable environmental conditions for life processes. Choices A, lack of cohesiveness, and C, use as a nonpolar solvent, are incorrect. Water actually has high cohesiveness due to its ability to form hydrogen bonds, and it is a polar solvent, not nonpolar. Choice B, low surface tension, is also incorrect as water's hydrogen bonding contributes to its relatively high surface tension.

5. If electrons are shared equally in a covalent bond, the bond is classified as what?

• A. Polar
• B. Non-polar
• C. Ionic
• D. Hydrogen

Correct answer: B

Rationale: The correct answer is B: Non-polar. In a non-polar covalent bond, electrons are shared equally between the atoms involved, leading to a balanced distribution of charge and no significant difference in electronegativity between the atoms. This equal sharing results in a non-polar bond. Choices A, C, and D are incorrect because a polar bond involves an unequal sharing of electrons, an ionic bond is formed by the transfer of electrons, and a hydrogen bond is a specific type of non-covalent bond.

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