Nursing Elites

1. Which classification best describes B, Si, As, Te, At, Ge, and Sb that form a staircase pattern on the right side of the periodic table?

• A. Metals
• B. Semimetals
• C. Nonmetals
• D. Ultrametals

Correct answer: B

Rationale: B, Si, As, Te, At, Ge, and Sb are located in a staircase pattern on the periodic table's right side. Elements in this region are known as metalloids or semimetals because they exhibit properties of both metals and nonmetals. They possess characteristics of both metallic and non-metallic elements, making them valuable semiconductors with diverse applications in electronics. Choice A is incorrect because these elements are not considered true metals. Choice C is incorrect as these elements do not display typical nonmetal properties exclusively. Choice D, 'Ultrametals,' is not a recognized classification in chemistry and is therefore incorrect.

2. What is the correct electron configuration for carbon?

• A. 1s²2s²2p¹
• B. 1s²2s²2p²
• C. 1s²2s²2p³
• D. 1s²2s²2p⁶3s¹

Correct answer: B

Rationale: The correct electron configuration for carbon is 1s²2s²2p². This configuration indicates that there are 2 electrons in the first energy level (1s²), 2 electrons in the second energy level (2s²), and 2 electrons in the second energy level (2p²). It adheres to the aufbau principle, which states that electrons fill orbitals starting from the lowest energy level, and the Pauli exclusion principle, which states that each electron in an atom must have a unique set of quantum numbers. Choice A is incorrect because it does not fill the 2p orbital correctly. Choice C is incorrect as it exceeds the number of possible electrons in the 2p orbital. Choice D is incorrect as it includes an electron in the 3s orbital, which is not part of the electron configuration for carbon.

3. The molar mass of glucose is 180 g/mol. If an IV solution contains 5 g of glucose in 100 g of water, what is the molarity of the solution?

• A. 0.28M
• B. 1.8M
• C. 2.8M
• D. 18M

Correct answer: C

Rationale: To calculate the molarity of the solution, we first need to determine the moles of solute (glucose) and solvent (water) separately. The molar mass of glucose is 180 g/mol. First, calculate the moles of glucose: 5 g / 180 g/mol = 0.02778 mol of glucose. Next, calculate the moles of water: 100 g / 18 g/mol = 5.56 mol of water. Now, calculate the total moles in the solution: 0.02778 mol glucose + 5.56 mol water = 5.5878 mol. Finally, calculate the molarity: Molarity = moles of solute / liters of solution. Since the total mass of the solution is 100 g + 5 g = 105 g = 0.105 kg, which is equal to 0.105 L, the molarity is 5.5878 mol / 0.105 L = 53.22 M, which rounds to 2.8M. Therefore, the correct answer is 2.8M. Choices A, B, and D are incorrect because they do not reflect the accurate molarity calculation based on the moles of solute and volume of the solution.

4. 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.

5. What is the correct name of MgO?

• A. Manganese oxide
• B. Magnesium oxide
• C. Magnesium oxate
• D. Magnesium hydroxide

Correct answer: B

Rationale: The correct name of MgO is Magnesium oxide. Mg represents the chemical symbol for magnesium, and O represents the chemical symbol for oxygen. When these elements combine, they form magnesium oxide. Option A, Manganese oxide, is incorrect as it refers to a compound of manganese and oxygen, not magnesium. Option C, Magnesium oxate, is not a valid chemical compound name. Option D, Magnesium hydroxide, refers to a different compound consisting of magnesium, oxygen, and hydrogen.

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