Nursing Elites

1. 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.

2. What is another name for aqueous HI?

• A. hydroiodic acid
• B. hydrogen monoiodide
• C. hydrogen iodide
• D. hydriodic acid

Correct answer: D

Rationale: The correct name for aqueous HI is 'hydriodic acid.' When hydrogen iodide (HI) dissolves in water, it forms hydriodic acid. Therefore, 'hydriodic acid' is the appropriate term for aqueous HI. Choice A, 'hydroiodic acid,' is incorrect as it does not reflect the nature of the compound in the aqueous state. Choice B, 'hydrogen monoiodide,' is not a widely recognized term for this compound. Choice C, 'hydrogen iodide,' is the name for HI in the gaseous state, not when it's dissolved in water.

3. In what type of covalent compounds are dispersion forces typically found?

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

Correct answer: B

Rationale: Dispersion forces, also known as London dispersion forces, are the weakest intermolecular forces that occur in non-polar covalent compounds. These forces result from temporary shifts in electron density within molecules, creating temporary dipoles. As a result, non-polar molecules, which lack a permanent dipole moment, can experience these dispersion forces. Polar compounds exhibit stronger intermolecular forces such as dipole-dipole interactions or hydrogen bonding, while ionic compounds involve electrostatic interactions between ions. Therefore, the correct answer is non-polar (choice B). Choices A, C, and D are incorrect because dispersion forces are typically found in non-polar covalent compounds, not polar, ionic, or hydrogen-bonded compounds.

4. Which ion would you expect to dominate in water solutions of bases?

• A. MgCl₂
• B. 2HCl
• C. H⁺
• D. OH⁻

Correct answer: D

Rationale: In water solutions of bases, the dominant ion would be OH⁻ (hydroxide ion). Bases release OH⁻ ions when dissolved in water, increasing the concentration of hydroxide ions and leading to a higher pH. This is in contrast to acids, which release H⁺ ions. Therefore, in water solutions of bases, the presence of OH⁻ ions signifies the basic nature of the solution. Choices A, B, and C are incorrect because MgCl₂ is a salt, 2HCl is a compound consisting of two hydrogen ions and one chloride ion, and H⁺ represents a hydrogen ion typically associated with acids, not bases.

5. A chemist takes 100 mL of a 40 g NaCl solution and dilutes it to 1L. What is the concentration (molarity) of the new solution?

• A. 0.04 M NaCl
• B. 0.25 M NaCl
• C. 0.40 M NaCl
• D. 2.5 M NaCl

Correct answer: C

Rationale: Initially, the chemist has 40 g of NaCl in 100 mL of solution. To find the initial molarity, we need to calculate the number of moles of NaCl using the molar mass of NaCl (58.44 g/mol). After dilution to 1 L, the molarity of the new solution can be calculated by dividing the moles of NaCl by the total volume in liters. Therefore, the concentration (molarity) of the new solution is 0.40 M NaCl. Choice A (0.04 M NaCl) is incorrect because it doesn't consider the correct molar concentration after dilution. Choice B (0.25 M NaCl) is incorrect as it also doesn't account for the correct molar concentration post-dilution. Choice D (2.5 M NaCl) is incorrect as it is too concentrated given the initial amount of NaCl and the dilution factor.

Similar Questions