Nursing Elites

1. What is the pH of a solution with a hydrogen ion concentration of (1x10^{-9}) M?

• A. 5
• B. 7
• C. 9
• D. 11

Correct answer: C

Rationale: The pH of a solution can be calculated using the formula: pH = -log[H+]. Given that the hydrogen ion concentration is \(1 \times 10^{-9}\) M, the pH can be calculated as pH = -log(1 x 10^-9) = 9. Therefore, the correct answer is C) 9.

2. Which of the following describes a scalar quantity?

• A. Velocity
• B. Acceleration
• C. Force
• D. Speed

Correct answer: D

Rationale: A scalar quantity is a physical quantity that has magnitude only, without any direction. Speed is an example of a scalar quantity because it only describes how fast an object is moving without specifying the direction of motion. Velocity, acceleration, and force are vector quantities because they have both magnitude and direction. Therefore, the correct answer is 'Speed.' Choices A, B, and C are incorrect because velocity, acceleration, and force are all vector quantities that involve both magnitude and direction.

3. What is the mass number of an element?

• A. The number of protons in an atom's nucleus.
• B. The number of neutrons in an atom's nucleus.
• C. The number of electrons in an atom's valence shell.
• D. The number of isotopes of an element.

Correct answer: B

Rationale: The mass number of an element represents the total number of protons and neutrons in an atom's nucleus. It specifically focuses on the number of neutrons in an atom's nucleus, which contributes to the overall mass of the atom. Therefore, the mass number is not solely determined by the number of protons, electrons, or isotopes. Choice A is incorrect because it refers to the atomic number, which is the number of protons in an atom's nucleus. Choice C is incorrect as the number of electrons in the valence shell is related to the atom's reactivity and bonding behavior, not the mass number. Choice D is incorrect because the mass number does not represent the number of isotopes of an element, but rather the sum of protons and neutrons in an atom's nucleus. Thus, option B, the number of neutrons in an atom's nucleus, is the correct choice.

4. What term describes the maximum displacement of particles from their rest position in a wave?

• A. Frequency
• B. Wavelength
• C. Amplitude
• D. Velocity

Correct answer: C

Rationale: The term that describes the maximum displacement of particles from their rest position in a wave is called the amplitude. Amplitude is a measure of the strength or intensity of a wave and is represented by the height of the wave from the rest position to the crest (or trough) of the wave. Frequency (A) refers to the number of complete wavelengths that pass a point in a given time. Wavelength (B) is the distance between two consecutive crests (or troughs) of a wave. Velocity (D) is the speed of the wave, not the maximum displacement of particles from their rest position.

5. Which statement is true about the pH of a solution?

• A. A solution cannot have a pH less than 0.
• B. A solution always has a pH of 7.
• C. A solution's pH is not influenced by its chemical composition.
• D. A solution with a pH of 14 is considered acidic.

Correct answer: A

Rationale: The pH scale ranges from 0 to 14, with 0 being the most acidic, 7 neutral, and 14 the most basic. A solution with a pH less than 0 would be outside the defined pH range, as 0 is the lower limit. Therefore, a solution cannot have a pH less than 0. Choice B is incorrect because a pH of 7 is considered neutral, not always the pH of a solution. Choice C is incorrect because a solution's pH is influenced by its chemical composition. Choice D is incorrect as a solution with a pH of 14 is considered highly basic, not acidic.

Similar Questions