chemical reaction involving two ionic compounds the reactant yields switched partners

HESI A2

Chemistry HESI A2 Quizlet

1. 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.

2. In what type of covalent compounds are dispersion forces typically found?

A. Polar
B. Non-polar
C. Ionic
D. Hydrogen

Correct answer: B

Rationale: Dispersion forces, also known as London dispersion forces, are the weakest intermolecular forces that occur in non-polar covalent compounds. These forces result from temporary shifts in electron density within molecules, creating temporary dipoles. As a result, non-polar molecules, which lack a permanent dipole moment, can experience these dispersion forces. Polar compounds exhibit stronger intermolecular forces such as dipole-dipole interactions or hydrogen bonding, while ionic compounds involve electrostatic interactions between ions. Therefore, the correct answer is non-polar (choice B). Choices A, C, and D are incorrect because dispersion forces are typically found in non-polar covalent compounds, not polar, ionic, or hydrogen-bonded compounds.

3. How many neutrons does carbon-14 have?

A. 10
B. 8
C. 6
D. 12

Correct answer: B

Rationale: The correct answer is B: 8. Carbon-14 is an isotope of carbon with 6 protons and 8 neutrons. To determine the number of neutrons in an atom, subtract the atomic number (number of protons) from the mass number. In this case, the mass number of carbon-14 is 14, and the atomic number of carbon is 6. Therefore, 14 (mass number) - 6 (atomic number) = 8 neutrons. Choices A, C, and D are incorrect because they do not reflect the correct number of neutrons in a carbon-14 atom.

4. When balanced, the reaction Fe + Oâ‚‚ â†’ FeO will be?

A. 2Fe + 2Oâ‚‚ â†’ 3FeO
B. 4Fe + 6Oâ‚‚ â†’ 6FeO
C. 2Fe + 3Oâ‚‚ â†’ 2FeO
D. 4Fe + 3Oâ‚‚ â†’ 2FeO

Correct answer: C

Rationale: To balance the chemical equation Fe + Oâ‚‚ â†’ FeO, the coefficients needed are 2 for Fe and 1 for O. Therefore, the balanced equation becomes 2Fe + Oâ‚‚ â†’ 2FeO, which translates into 2Fe + 3Oâ‚‚ â†’ 2FeO. This corresponds to option C. Choice A has the incorrect number of oxygen molecules. Choice B has an incorrect number of Fe atoms on the product side. Choice D also has an incorrect number of Fe atoms on the product side.

5. What is the name of the bond formed when two atoms share electrons?

A. Covalent bond
B. Ionic bond
C. Metallic bond
D. Hydrogen bond

Correct answer: A

Rationale: A covalent bond is formed when two atoms share electrons, creating a stable electron configuration. This sharing allows both atoms to achieve a full outer shell of electrons, leading to a stable molecule. In contrast, an ionic bond involves the transfer of electrons from one atom to another, resulting in the formation of ions with opposite charges. Metallic bonds are formed between metal atoms and involve a 'sea of electrons' that are delocalized and free to move. Hydrogen bonds are a type of intermolecular force, not a true chemical bond, and occur between a hydrogen atom and a highly electronegative atom like oxygen or nitrogen.