Nursing Elites

1. How many moles of water are produced when 0.5 moles of methane (CH4) react with excess oxygen?

• A. 0.5 moles
• B. 1 mole
• C. 2 moles
• D. 3 moles

Correct answer: B

Rationale: The balanced chemical equation for the combustion of methane is: CH4 + 2O2 -> CO2 + 2H2O. This equation shows that 1 mole of methane produces 2 moles of water. Therefore, when 0.5 moles of methane react, they will produce 1 mole of water. The ratio of water to methane is 2:1, meaning that for every mole of methane that reacts, it produces 2 moles of water. Since only 0.5 moles of methane are reacting, the amount of water produced will be half of what would be produced if 1 mole of methane reacted, resulting in 1 mole of water being produced. Choice A is incorrect because it does not consider the stoichiometry of the reaction. Choices C and D are incorrect as they do not align with the balanced chemical equation and the stoichiometric ratios involved in the reaction.

2. Tendonitis is an inflammation of which part of the body?

• A. Muscles
• B. Tendons
• C. Ligaments
• D. Cartilage

Correct answer: B

Rationale: Tendonitis specifically refers to the inflammation of tendons, which are the thick cords that connect muscles to bones. The correct answer is tendons. Choice A, muscles, are not affected in tendonitis, but rather in myositis, which is the inflammation of muscles. Ligaments (Choice C) connect bones to other bones, while cartilage (Choice D) is a smooth and flexible tissue that covers the ends of bones at a joint. Therefore, the correct term for inflammation of tendons is tendonitis.

3. Which structure in the skin is responsible for producing hair?

• A. Sudoriferous gland
• B. Sebaceous gland
• C. Melanocyte
• D. Hair follicle

Correct answer: D

Rationale: The correct answer is D: Hair follicle. Hair follicles are structures in the skin responsible for producing hair. They are specialized structures that contain the hair root and the bulb, where hair growth originates. Sudoriferous glands produce sweat, sebaceous glands produce sebum, and melanocytes are responsible for producing melanin, the pigment that gives hair and skin their color. Choices A, B, and C are incorrect because sudoriferous glands produce sweat, sebaceous glands produce sebum, and melanocytes produce melanin, respectively, but they are not responsible for producing hair.

4. What does half-life refer to?

• A. Radioactive intensity to completely disappear
• B. The number of neutrons in a nucleus to double
• C. The number of protons in a nucleus to change
• D. An isotope to decay by half of its initial quantity

Correct answer: D

Rationale: Half-life refers to the time it takes for half of the radioactive atoms in a sample to decay. This means that after one half-life, half of the initial quantity of the radioactive substance will have decayed. Choice A is incorrect because radioactive intensity doesn't completely disappear during half-life. Choice B is incorrect as half-life doesn't refer to the number of neutrons doubling. Choice C is incorrect as half-life doesn't relate to the number of protons changing.

5. Which statement correctly describes the concept of ionization energy?

• A. The energy required to remove an electron from an outermost shell.
• B. The energy released when an electron bonds with an atom.
• C. The total energy possessed by all electrons in an atom.
• D. The energy needed to change an atom's nucleus.

Correct answer: A

Rationale: Ionization energy is defined as the energy required to remove an electron from an atom in the gaseous state. This process typically involves removing an electron from the outermost shell of the atom. Therefore, option A accurately describes the concept of ionization energy. The other choices do not accurately describe ionization energy; option B refers to bond formation energy, option C is about the total energy of electrons in an atom, and option D relates to nuclear energy changes, not ionization energy.

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