what is the normal body temperature in f

HESI A2

Chemistry HESI A2 Practice Test

1. What is the normal body temperature in Fahrenheit?

A. 96°F
B. 98.6°F
C. 100°F
D. 95°F

Correct answer: B

Rationale: The normal body temperature for humans is 98.6°F, which is equivalent to 37°C. This temperature is considered the average baseline for most individuals when measured orally. Choice A (96°F) is too low for normal body temperature. Choice C (100°F) is too high for normal body temperature. Choice D (95°F) is also lower than the normal body temperature range. Therefore, the correct answer is B, 98.6°F.

2. What is the oxidation state of the chlorine atom in the compound HCl?

A. +1
B. -1
C. +2
D. -2

Correct answer: B

Rationale: In the compound HCl (hydrochloric acid), the hydrogen atom has an oxidation state of +1 based on the rules of assigning oxidation states. Since the overall compound is neutral, the oxidation state of chlorine must be -1 to balance the charge. Chlorine typically has an oxidation state of -1 in binary compounds with nonmetals, such as HCl. Therefore, the correct answer is -1. Choices A, C, and D are incorrect as the oxidation state of chlorine in HCl is -1, not +1, +2, or -2.

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

A. Dipole-dipole interaction
B. London dispersion force
C. Keesom interaction
D. Hydrogen bonding

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.

4. What does the mass number minus the atomic number equal?

A. Number of electrons
B. Number of neutrons
C. Number of protons
D. Number of isotopes

Correct answer: B

Rationale: The mass number of an atom represents the total number of protons and neutrons in its nucleus. The atomic number indicates the number of protons in the nucleus. The difference between the mass number and the atomic number provides the number of neutrons present in the nucleus of an atom. Therefore, mass number minus atomic number equals the number of neutrons. Choice A is incorrect because the number of electrons is not determined by the mass number and atomic number. Choice C is incorrect as it represents the number of protons, not the difference between the mass number and atomic number. Choice D is incorrect as isotopes refer to atoms of the same element with different numbers of neutrons, not the difference between mass number and atomic number.

5. Balance this equation: Zn + HCl → ZnCl + H2.

A. Zn + 2HCl → ZnCl + H2
B. Zn + HCl → 2ZnCl + H2
C. 2Zn + 2HCl → 2ZnCl + H2
D. Zn + 4HCl → ZnCl + H2

Correct answer: C

Rationale: The given unbalanced equation is Zn + HCl → ZnCl + H2. To balance it, we need to have equal atoms on both sides of the equation. The balanced equation is 2Zn + 2HCl → 2ZnCl + H2. This balanced equation shows that two atoms of Zn combine with two molecules of HCl to form two molecules of ZnCl and one molecule of H2. Choice A is incorrect because it does not balance the equation. Choice B is incorrect as it does not have the same number of atoms on both sides. Choice D is incorrect because it does not balance the equation properly, resulting in an unequal number of atoms on both sides.