HESI A2
HESI A2 Version 1 Chemistry Questions
Extract:
Question 1 of 5
Which of the following states of matter exhibits the most molecular motion?
Correct Answer: C
Rationale: The correct answer is 'C: Gas'. Gas exhibits the most molecular motion compared to solid and liquid states. In a gas state, molecules possess high kinetic energy, are spaced far apart, and move freely in all directions. This results in increased molecular motion compared to the more structured and restricted motion observed in solids and liquids. In solids, molecules are tightly packed and have minimal movement, while in liquids, although the molecules are more mobile than in solids, they are still more constrained compared to gases. Therefore, gas stands out as the state of matter with the highest molecular motion due to the high energy and freedom of movement of its molecules.
Question 2 of 5
What is the correct name for aqueous HI?
Correct Answer: A
Rationale: The correct name for aqueous HI is hydroiodic acid. In the naming of binary acids, the prefix 'hydro-' is combined with the root of the nonmetal element and the suffix '-ic acid'. Therefore, the correct systematic name for HI in aqueous solution is hydroiodic acid.
Question 3 of 5
What is the name for the horizontal rows of the periodic table?
Correct Answer: B
Rationale: In the periodic table, the horizontal rows are called 'periods.' These periods represent the number of electron shells an element has. Each period starts a new energy level, indicating the elements' properties and atomic structure. 'Groups' refer to the vertical columns of the periodic table, each containing elements with similar chemical properties. 'Families' can also be used interchangeably with groups. 'Sets' is a vague term and not specifically related to the layout of the periodic table. Understanding the distinction between 'periods' and 'groups' is crucial in comprehending the organization and properties of elements in the periodic table.
Question 4 of 5
What is a benefit of water's ability to make hydrogen bonds?
Correct Answer: D
Rationale: The correct answer is D - High specific heat. Water's ability to make hydrogen bonds leads to a high specific heat capacity, which allows it to absorb and release large amounts of heat with minimal temperature change. This property is crucial for maintaining stable temperatures in living organisms and aquatic environments. High specific heat helps regulate body temperature in organisms and prevents sudden temperature fluctuations in water bodies, providing an essential benefit for various biological processes.
Question 5 of 5
What are bases or alkaline solutions known as?
Correct Answer: A
Rationale: Bases or alkaline solutions are substances that can accept protons (H+ ions), making them hydrogen acceptors. When a base reacts with an acid, it accepts a proton to form water, hence neutralizing the acid. This property distinguishes bases from acids, which donate protons (H+ ions). Therefore, the correct answer is that bases or alkaline solutions are known as hydrogen acceptors.