chemistry hesi a2 Chemistry Hesi A2 - Nursing Elites
Logo

Nursing Elites

HESI A2

Chemistry Hesi A2

1. Which of these intermolecular forces might represent attraction between atoms of a noble gas?

Correct answer: B

Rationale: Noble gases are non-polar molecules without a permanent dipole moment. The only intermolecular force applicable to noble gases is the London dispersion force, also known as Van der Waals forces. This force is a temporary attractive force resulting from the formation of temporary dipoles in non-polar molecules. Dipole-dipole interactions, Keesom interactions, and hydrogen bonding involve significant dipoles or hydrogen atoms bonded to electronegative atoms, which do not apply to noble gases.

2. What does a blood sample with a pH of 3 indicate?

Correct answer: A

Rationale: A blood pH of 3 is significantly low, indicating a strong acidity level. The normal blood pH range is 7.35 to 7.45; therefore, a pH of 3 is far below the normal range, showing a highly acidic condition in the blood sample. Choice B is incorrect because a pH of 3 is not basic at all. Choice C is incorrect as a pH of 3 is not weakly acidic but strongly acidic. Choice D is wrong as a blood pH of 3 does not indicate a weakly basic condition.

3. Why does fluorine have a higher ionization energy than oxygen?

Correct answer: D

Rationale: Fluorine has a higher ionization energy than oxygen because fluorine has a larger nuclear charge. The greater number of protons in the nucleus of fluorine attracts its electrons more strongly, making it harder to remove an electron from a fluorine atom compared to an oxygen atom. Choice A is incorrect as the number of neutrons does not directly affect ionization energy. Choice B is also incorrect for the same reason. Choice C is incorrect because a smaller nuclear charge would result in lower ionization energy, not higher.

4. What is the oxidation state of the nitrogen atom in the compound NH3?

Correct answer: B

Rationale: In the compound NH3, nitrogen is bonded to three hydrogen atoms. Hydrogen is always assigned an oxidation state of +1. Since the overall charge of NH3 is zero, the oxidation state of nitrogen must be -1 to balance out the hydrogen's +1 oxidation state. Therefore, the correct oxidation state of the nitrogen atom in NH3 is -1. Choice A (-3) is incorrect because it does not account for the electronegativity of hydrogen. Choice C (+1) and Choice D (+3) are incorrect as the nitrogen atom in NH3 needs to balance the +1 oxidation state of each hydrogen atom, resulting in a total of -3 to maintain the compound's charge neutrality.

5. Which is a triatomic allotrope of oxygen?

Correct answer: A

Rationale: Ozone (O3) is a triatomic allotrope of oxygen. It differs from the common diatomic oxygen molecule (O2) by having three oxygen atoms bonded together. Ozone is known for its protective role in the Earth's atmosphere, absorbing most of the Sun's harmful ultraviolet radiation. Water (H2O) is a compound composed of two hydrogen atoms and one oxygen atom. Acidic oxide and carbon dioxide are not triatomic allotropes of oxygen. Carbon dioxide consists of one carbon atom and two oxygen atoms, while acidic oxides refer to compounds where oxygen is bonded with other elements to form oxides, and they are not allotropes of oxygen.

Similar Questions

What is the correct name of MgO?
Aluminum (Al) has 13 protons in its nucleus. What is the number of electrons in an Al3+ ion?
Which of the following compounds is ionic?
A chemist takes 100 mL of a 40 g NaCl solution and dilutes it to 1L. What is the concentration (molarity) of the new solution?
What is the charge of a gamma ray?
ATI TEAS 7 Exam Overview

Access More Features

HESI A2 Basic
$99/ 30 days

  • 3,000 Questions with answers
  • 30 days access @ $99

HESI A2 Premium
$149.99/ 90 days

  • Actual HESI A 2 Questions
  • 3,000 questions with answers
  • 90 days access @ $149.99