what creates a dipole

HESI A2

Chemistry HESI A2 Quizlet

1. What creates a dipole in a covalent bond?

A. Unequal sharing of electrons
B. Equal sharing of electrons
C. Exchange of electrons
D. Transfer of electrons

Correct answer: A

Rationale: A dipole is created in a covalent bond when there is an unequal sharing of electrons between the atoms involved. This results in a partial positive charge on one atom and a partial negative charge on the other, leading to a separation of charges and the formation of a dipole. Choices B, C, and D are incorrect because a dipole is specifically formed due to unequal sharing of electrons, not equal sharing, exchange, or transfer of electrons in a covalent bond.

2. Which type of chemical reaction involves an active metal reacting with an ionic compound to create a new compound?

A. Combustion
B. Single replacement
C. Synthesis
D. Decomposition

Correct answer: B

Rationale: The correct answer is 'Single replacement.' In a single replacement reaction, an active metal replaces another element in an ionic compound, resulting in the formation of a new compound. Option A, 'Combustion,' involves a substance rapidly reacting with oxygen to release energy in the form of heat and light. Option C, 'Synthesis,' involves the combination of two or more substances to form a more complex product. Option D, 'Decomposition,' involves the breakdown of a compound into simpler substances.

3. What is the correct electron configuration for nitrogen?

A. 1s² 2s²
B. 1s² 2s² 2p²
C. 1s² 2s² 2p³
D. 1s² 2s² 2p⁴

Correct answer: C

Rationale: The electron configuration of nitrogen is determined by its atomic number, which is 7. Nitrogen has 7 electrons. Following the order of filling orbitals, the electron configuration for nitrogen is 1s² 2s² 2p³. This means the first energy level is filled with 2 electrons in the 1s orbital, the second energy level is filled with 2 electrons in the 2s orbital, and 3 electrons in the 2p orbital. Each orbital can hold a specific number of electrons, and nitrogen, with its 7 electrons, fits this configuration. Choice A is incorrect because it does not account for all the electrons in the nitrogen atom. Choice B is incorrect as it only represents 6 electrons, not the 7 electrons in nitrogen. Choice D is incorrect as it represents 8 electrons, which is not the correct electron configuration for nitrogen.

4. Which type of chemical reaction involves two ionic compounds where the reactants yield 'switched partners'?

A. Single replacement
B. Double replacement
C. Synthesis
D. Decomposition

Correct answer: B

Rationale: The correct answer is 'Double replacement.' In a double replacement reaction, two ionic compounds react by exchanging ions, resulting in the formation of two new compounds where the positive and negative ions have 'switched partners.' This type of reaction is characterized by the exchange of ions between the reactants. Choice A, 'Single replacement,' involves an element replacing another in a compound, not the exchange of partners like in the given scenario. Choice C, 'Synthesis,' is the combination of two or more substances to form a more complex product, not involving the exchange of partners. Choice D, 'Decomposition,' is the breakdown of a compound into simpler substances, which is different from the scenario described in the question.

5. Aluminum (Al) has 13 protons in its nucleus. What is the number of electrons in an Al3+ ion?

A. 16
B. 13
C. 10
D. 3

Correct answer: C

Rationale: Aluminum (Al) has an atomic number of 13, which indicates it normally has 13 electrons to balance the 13 protons in its nucleus. When Al forms an Al3+ ion, it loses 3 electrons to achieve a stable electron configuration. Therefore, the Al3+ ion will have 13 - 3 = 10 electrons. Choice A (16) is incorrect as it doesn't take into account the charge of the Al3+ ion. Choice B (13) is incorrect because the Al3+ ion has lost electrons. Choice D (3) is incorrect as it doesn't reflect the total number of electrons lost by the Al atom to form the Al3+ ion.