HESI A2 Chemistry Questions - Nurselytic

Correct Answer: B

Rationale: The correct answer is B: Condensation. Condensation is the process where gas transforms into a liquid. When gas cools down, it loses energy and its particles come closer, leading to the formation of liquid droplets. Sublimation is the direct transition from solid to gas without passing through the liquid state. Evaporation is the process of liquid turning into a gas, and deposition is the transition of gas directly into a solid.
Therefore, choices A, C, and D are incorrect as they describe different phase transitions.

Correct Answer: A

Rationale: The correct answer is 'boron.' Diatomic molecules consist of two atoms of the same element bonded together. Boron is an exception and does not exist naturally as a diatomic molecule. On the other hand, fluorine, oxygen, and nitrogen commonly exist as diatomic molecules in their natural states. Fluorine, for example, exists as F2, oxygen exists as O2, and nitrogen exists as N2.

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.

Correct Answer: B

Rationale: The correct answer is Group 1. Alkali metals are found in Group 1 of the periodic table, which includes elements such as lithium, sodium, and potassium. These elements are known for their high reactivity and tendency to form alkaline solutions when they react with water.
Therefore, Group 1 is specifically designated as the group containing alkali metals.
Choice A (Group 7) is incorrect as Group 7 contains the halogens.
Choice C (Group 2) is incorrect as Group 2 contains the alkaline earth metals.
Choice D (Group 3) is incorrect as Group 3 contains the scandium group of elements.

Correct Answer: B

Rationale: An exothermic reaction is characterized by the release of heat. During an exothermic reaction, energy is released in the form of heat to the surroundings, resulting in a temperature increase. This distinguishes it from endothermic reactions, which absorb heat from the surroundings.
Choice A is incorrect because exothermic reactions do not absorb heat; instead, they release heat.
Choice C is incorrect as exothermic reactions do not remain neutral; they involve a net release of energy.
Choice D is incorrect as exothermic reactions do not require energy input; instead, they release energy.