Health Educational Systems Health Educational Systems Certifications HESI Questions & Answers

• Question 221:

  An unknown element has a mass number of 33 and an atomic number of 12. How many neutrons does the element contain?

  A. 21

  B. 12

  C. 33

  D. 45

  Correct Answer: A

• Question 222:

  Rank the following intermolecular forces in decreasing strength: hydrogen bonding, London dispersion forces, ion-dipole interactions, ion bonding, and dipole-dipole interactions.

  A. ionic bonding > dipole-dipole interactions > ion-dipole interactions > hydrogen bonding > London dispersion forces

  B. ionic bonding > hydrogen bonding > ion-dipole interactions > dipole-dipole interactions > London dispersion forces

  C. ionic bonding < ion-dipole interactions < dipole-dipole interactions < hydrogen bonding < London dispersion forces

  D. ionic bonding > ion-dipole interactions > hydrogen bonding > dipole-dipole interactions > London dispersion forces

  Correct Answer: D

• Question 223:

  An unknown element is found to contain 45 protons and an atomic mass of 64, what is its atomic number?

  A. It cannot be determined.

  B. 19

  C. 45

  D. 64

  Correct Answer: C

• Question 224:

  Elements that are in the same column of the periodic table are in the same:

  A. period.

  B. group.

  C. row.

  D. classification

  Correct Answer: B

• Question 225:

  What is the purpose of scientific notation?

  A. There is no purpose.

  B. The purpose is to handle bigger numbers more easily.

  C. The purpose is to handle smaller numbers more easily.

  D. The purpose is to handle both smaller and bigger numbers more easily.

  Correct Answer: D

• Question 226:

  What is the metric prefix meaning one billionth?

  A. Nano

  B. Milli

  C. Micro

  D. Pico

  Correct Answer: A

• Question 227:

  The breakdown of ____ provides the energy needed for chemical reactions in the body.

  A. RNA

  B. ATP

  C. ADP

  D. ATE

  Correct Answer: B

• Question 228:

  Which of the following statements about atoms is false?

  A. Electrons do not orbit an atom's nucleus; they exist in electron clouds surrounding the nucleus.

  B. As each orbital of an atom is filled to capacity, electrons begin occupying a higher energy orbital.

  C. Most of the volume of an atom is empty space.

  D. Atoms are most stable when their outer electron shell (valence shell) is incomplete.

  Correct Answer: D

• Question 229:

  What are isotopes?

  A. Elements which have the same number of protons but a different number of neutrons.

  B. Elements with the same atomic number but different atomic mass numbers.

  C. Elements which have a different number of protons than electrons.

  D. Both A and B are correct.

  Correct Answer: D

• Question 230:

  What is the charge on sodium in the compound NaCl?

  A. -1

  B. 0

  C. +1

  D. +2

  Correct Answer: C