HESI A2 Chemistry Practice Test

Correct Answer: D

Rationale: Rationale: 1. Wavelength is defined as the distance between adjacent peaks or troughs on a wave. 2. Frequency is the number of wave cycles per unit time, not the distance between peaks/troughs. 3. Wavenumber is the spatial frequency of a wave, not the distance between peaks/troughs. 4. Wave oscillation refers to the movement of particles in a wave, not the distance between peaks/troughs. Summary: The correct answer is D because wavelength specifically refers to the distance between adjacent peaks or troughs on a wave, whereas the other choices are related to different properties of waves.

Correct Answer: C

Rationale: Henry's Law states that the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas above the liquid (P = kC). This means that as the partial pressure of the gas increases, the amount of gas that dissolves in the liquid also increases. This relationship is specifically for gases and volatile substances in liquids. Boyle's Law relates pressure and volume, Gay-Lussac's Law relates pressure and temperature, and Charles' Law relates volume and temperature. Therefore, the correct answer is C, Henry's Law, because it directly describes the relationship between gas solubility and partial pressure.

Correct Answer: B

Rationale: The correct answer is B: 6. In sulfuric acid (H2SO4), the oxidation states of hydrogen and oxygen are always +1 and -2, respectively. Since the overall charge of the molecule is 0, the sum of the oxidation states must equal 0. Given that there are two hydrogen atoms (each with an oxidation state of +1) and four oxygen atoms (each with an oxidation state of -2), the oxidation state of sulfur (S) can be calculated as follows: 2(+1) + x + 4(-2) = 0. Solving for x gives x = +6, indicating that the oxidation state of the sulfur atom in sulfuric acid is indeed +6. Summary: A: 4 - Incorrect. This value does not account for the correct oxidation state calculation in sulfuric acid. C: 8 - Incorrect. This value is too high and does not align with the correct oxidation state calculation. D:

Correct Answer: B

Rationale: Failed to generate a rationale after 5 retries.

Correct Answer: A

Rationale: Rationale: A is false because in an endothermic process, solubility usually increases with increasing temperature and decreases with decreasing temperature due to the absorption of heat. B is true, as solubility generally decreases with increasing temperature in exothermic processes. C and D are incorrect as A is false.