Nursing Elites

1. How many electrons are typically found in each shell of a neutral aluminum atom with 13 electrons in its electron cloud?

• A. 6 in the first shell, 7 in the second shell
• B. 2 in the first shell, 11 in the second shell
• C. 2 in the first shell, 8 in the second shell, 3 in the third shell
• D. 3 in the first shell, 5 in the second shell, 5 in the third shell

Correct answer: C

Rationale: In a neutral aluminum atom with 13 electrons, the electron distribution typically follows the electron shell filling order based on the Aufbau principle. The first shell can hold a maximum of 2 electrons, the second shell can hold up to 8 electrons, and the third shell can hold up to 8 electrons as well. Therefore, the distribution would be 2 electrons in the first shell, 8 electrons in the second shell, and 3 electrons in the third shell, totaling 13 electrons. Choice A is incorrect as it exceeds the maximum number of electrons the shells can hold. Choice B is incorrect as it does not distribute the electrons correctly among the shells. Choice D is incorrect as it also does not distribute the electrons correctly among the shells.

2. Melanin, the pigment responsible for skin color, is produced by

• A. Keratinocytes (These cells produce keratin)
• B. Melanocytes
• C. Sebocytes (These cells produce sebum)
• D. Langerhans cells (These cells are part of the immune system)

Correct answer: B

Rationale: Melanocytes are the cells responsible for producing melanin, the pigment that determines skin color. Melanin gives skin its color and protects it from the harmful effects of UV radiation. Keratinocytes produce keratin, a tough protein that forms the outer layer of the skin, hair, and nails. Sebocytes produce sebum, an oily substance that helps moisturize and protect the skin. Langerhans cells are a type of immune cell found in the skin that play a role in protecting against infections and foreign substances but do not produce melanin.

3. What are isotopes?

• A. Atoms of the same element with different numbers of protons.
• B. Atoms of the same element with different numbers of neutrons.
• C. Atoms of different elements with the same number of protons.
• D. Atoms of different elements with the same number of electrons.

Correct answer: B

Rationale: Isotopes are atoms of the same element with different numbers of neutrons. While isotopes share the same number of protons, which determines the element, they differ in the number of neutrons. This variance in neutron count results in isotopes having different atomic masses. Choice A is incorrect because isotopes have the same number of protons (same element) but differ in the number of neutrons. Choice C is incorrect as it describes atoms of different elements, not isotopes of the same element. Choice D is also incorrect because isotopes can have different numbers of electrons, but what defines isotopes is the variation in neutron numbers.

4. Which type of joint connects the bones of the skull?

• A. Synovial
• B. Fibrous
• C. Cartilaginous
• D. Ball-and-socket

Correct answer: B

Rationale: Fibrous joints connect the bones of the skull. These joints are immovable or provide very limited movement, providing stability and protection to the brain. Synovial joints (Choice A) are found in the limbs and allow for a wide range of movements. Cartilaginous joints (Choice C) are connected by cartilage and allow limited movement. Ball-and-socket joints (Choice D) allow for a wide range of motion, such as the hip and shoulder joints, but they do not connect the bones of the skull.

5. Which of the following factors does NOT affect the rate of dissolution of a solute in a solvent?

• A. Temperature
• B. Pressure
• C. Surface area
• D. Particle size

Correct answer: B

Rationale: Pressure does not affect the rate of dissolution of a solute in a solvent. The factors that affect the rate of dissolution include temperature, surface area, and particle size. Temperature generally increases the rate of dissolution by providing more energy for the solute particles to break apart and mix with the solvent. Increasing the surface area of the solute by grinding it into smaller particles or increasing its contact area with the solvent can also speed up dissolution. Similarly, reducing the particle size of the solute can increase the rate of dissolution by providing more surface area for interaction with the solvent. Pressure, however, does not have a significant impact on the dissolution process and is not a factor that influences the rate at which a solute dissolves in a solvent.

Similar Questions