which is true of a saturated solution

HESI A2

HESI A2 Chemistry Practice Questions

1. Which statement is true of a saturated solution?

A. It has more solute than can dissolve in the solvent.
B. It has less solute that can dissolve in the solvent.
C. It has the maximum concentration of the solute dissolved in the solvent.
D. It contains a precipitate that lowers the concentration of the solute in the solvent.

Correct answer: C

Rationale: A saturated solution contains the maximum concentration of solute that can be dissolved in a specific amount of solvent at a particular temperature. Once a solution is saturated, adding more solute will not increase its concentration since the excess solute will not dissolve and will instead form a precipitate, indicating that the solution is at its maximum capacity. Choices A, B, and D are incorrect because a saturated solution has reached its limit in dissolving solute, so it cannot contain more solute than it can dissolve (choice A), less solute than it can dissolve (choice B), or a precipitate that lowers the concentration of the solute in the solvent (choice D).

2. What are the 3 types of radiation in nuclear chemistry?

A. Alpha, Beta, Delta
B. Alpha, Beta, Gamma
C. Gamma, Beta, Delta
D. Delta, Beta, Gamma

Correct answer: B

Rationale: The correct answer is B: Alpha, Beta, Gamma. In nuclear chemistry, the 3 types of radiation are alpha, beta, and gamma radiation. Alpha radiation consists of helium nuclei, beta radiation involves electrons or positrons, and gamma radiation is electromagnetic radiation of high frequency. Choice A is incorrect because 'Delta' is not a type of radiation in nuclear chemistry. Choice C is incorrect as it does not list alpha radiation. Choice D is incorrect as it lists the types in the wrong order and includes 'Delta' instead of alpha radiation.

3. Which of the following elements is a halogen?

A. Oxygen
B. Fluorine
C. Sodium
D. Carbon

Correct answer: B

Rationale: The correct answer is 'Fluorine' (Choice B) as it is a halogen. Halogens are a group of elements that include fluorine, chlorine, bromine, iodine, and astatine. They are highly reactive nonmetals located in Group 17 of the periodic table. Oxygen (Choice A) is a nonmetal but not a halogen. Sodium (Choice C) is a metal, and Carbon (Choice D) is a nonmetal, neither of which belong to the halogen group.

4. What is the correct electron configuration for carbon?

A. 1sÂ²2sÂ²2pÂ¹
B. 1sÂ²2sÂ²2pÂ²
C. 1sÂ²2sÂ²2pÂ³
D. 1sÂ²2sÂ²2pâ¶3sÂ¹

Correct answer: B

Rationale: The correct electron configuration for carbon is 1sÂ²2sÂ²2pÂ². This configuration indicates that there are 2 electrons in the first energy level (1sÂ²), 2 electrons in the second energy level (2sÂ²), and 2 electrons in the second energy level (2pÂ²). It adheres to the aufbau principle, which states that electrons fill orbitals starting from the lowest energy level, and the Pauli exclusion principle, which states that each electron in an atom must have a unique set of quantum numbers. Choice A is incorrect because it does not fill the 2p orbital correctly. Choice C is incorrect as it exceeds the number of possible electrons in the 2p orbital. Choice D is incorrect as it includes an electron in the 3s orbital, which is not part of the electron configuration for carbon.

5. Which gas is released during photosynthesis?

A. Carbon dioxide
B. Oxygen
C. Nitrogen
D. Helium

Correct answer: B

Rationale: During photosynthesis, plants utilize carbon dioxide and water to produce glucose and oxygen. Oxygen is released as a byproduct of this process, which is essential for the survival of most living organisms that depend on it for respiration. Therefore, the correct answer is oxygen. Choices A, C, and D are incorrect. Carbon dioxide is utilized in photosynthesis, nitrogen is not directly involved in the process, and helium is not a gas released during photosynthesis.