what is a mole
Logo

Nursing Elites

HESI A2

Chemistry HESI A2 Quizlet

1. What is a mole?

Correct answer: A

Rationale: A mole is a unit used in chemistry to represent Avogadro's number, which is approximately 6.02 x 10^23. This number corresponds to the number of particles (atoms, molecules, ions) in one mole of a substance. Choice A, 6.02 x 10^23, is the correct answer as it accurately defines a mole. Choices B, C, and D provide values that are not equivalent to Avogadro's number, making them incorrect answers.

2. What effect does increasing the surface area of a reactant have?

Correct answer: C

Rationale: Increasing the surface area of a reactant leads to more particles being exposed to the reaction, which in turn increases the reaction rate. This is because a larger surface area provides more sites for collisions between reacting particles, resulting in a higher frequency of successful collisions and thus accelerating the reaction. Choice A, 'Decreases the reaction rate,' is incorrect because increasing surface area actually accelerates the reaction. Choice B, 'Has no effect,' is incorrect as increasing surface area does have a significant effect on the reaction rate. Choice D, 'Stops the reaction,' is incorrect as increasing surface area does not stop the reaction but rather enhances it.

3. Which factor does not affect the reaction rate of a chemical reaction?

Correct answer: D

Rationale: The color of reactants is not a factor that affects the rate of a chemical reaction. Temperature, surface area, and concentration of reactants are known factors that influence the reaction rate. Temperature plays a significant role in altering the reaction rate by affecting the kinetic energy of molecules. Surface area impacts the rate by providing more area for collisions to occur. Concentration affects the frequency of effective collisions. On the other hand, the color of reactants is a physical property that does not directly affect the speed of a chemical reaction.

4. What charge do alpha radiation particles have?

Correct answer: C

Rationale: The correct answer is C: +2. Alpha radiation particles consist of two protons and two neutrons, giving them a net charge of +2. This positive charge is due to the presence of the two protons in the nucleus of the alpha particle. Choice A (-2) is incorrect as alpha particles have a positive charge. Choice B (0) is incorrect as alpha particles carry a charge. Choice D (+1) is incorrect as alpha particles have a higher positive charge due to the presence of two protons.

5. Which of the following can act as a catalyst in a chemical reaction?

Correct answer: A

Rationale: Enzymes are biological catalysts that speed up chemical reactions without being consumed. They lower the activation energy required for the reaction to occur, facilitating and accelerating the process. Choice B, Light, is not a catalyst but can sometimes trigger reactions by providing energy. Choice C, Water, and choice D, Metal, are not catalysts but can participate in reactions as reactants.

Similar Questions

Which is a property of an ionic compound?
A salt solution has a molarity of 5 M. How many moles of this salt are present in 0 L of this solution?
Arsenic and silicon are examples of ___________.
Which two functional groups would you expect an amino acid to contain?
What is the chemical reaction that involves breaking down a compound into component parts?

Access More Features

HESI A2 Basic
$49/ 30 days

  • 3,000 Questions with answers
  • 30 days access

HESI A2 Premium
$99/ 90 days

  • Actual HESI A2 Questions
  • 3,000 questions with answers
  • 90 days access

Other Courses