HESI A2
HESI A2 Version 1 Chemistry Questions
Question 1 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 2 of 5
What can be predicted by using the periodic table?
Correct Answer: A
Rationale: The periodic table organizes elements based on their properties, such as atomic number, electron configuration, and chemical behavior. By examining an element's position on the periodic table, one can predict its properties, including its physical and chemical characteristics, reactivity, and other behaviors. This predictive ability is one of the fundamental strengths of the periodic table in understanding and working with elements. Therefore, the correct answer is A, as the periodic table allows for the prediction of the properties of each element based on its location and characteristics within the table.
Question 3 of 5
What can be predicted by using the periodic table?
Correct Answer: A
Rationale: The periodic table is a fundamental tool in chemistry that organizes elements based on their properties. By using the periodic table, scientists can predict the properties of each element. The arrangement of elements in the table groups together elements with similar characteristics, allowing for the prediction of various properties such as reactivity, atomic size, and electronegativity. These predictions are possible because elements in the same group or period exhibit similar chemical behaviors. Therefore, the correct answer is A: The properties of each of the elements.
Question 4 of 5
What is the pH of a solution with a pH of 7?
Correct Answer: C
Rationale: The correct answer is C: Neutral. A pH of 7 is considered neutral on the pH scale, which ranges from 0 to 14. A pH of 7 indicates a balance between acidic and basic properties in a solution, making it neither acidic nor basic. Values below 7 are acidic, above 7 are basic, and 7 is the midpoint representing neutrality. Therefore, a solution with a pH of 7 is neutral.
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.