Chemistry HESI A2 Quizlet

Correct Answer: B

Rationale: The correct answer is B: Nuclear. Nuclear reactions involve changes in the nucleus of an atom, such as nuclear fusion or fission, to achieve stable nuclear configurations by balancing the number of protons and neutrons. Chemical reactions (Choice A) involve changes in electron configurations, not the nucleus. Physical reactions (Choice C) involve changes in state or structure, not nuclear configurations. Mechanical reactions (Choice D) involve forces and motion, not changes in the nucleus for stability. Therefore, option B is the correct choice for reactions taking place in the nucleus to achieve stable nuclear configurations.

Correct Answer: B

Rationale: The correct answer is B, the Law of Conservation of Mass. This law states that matter cannot be created or destroyed in a chemical reaction, only rearranged. This is based on the principle of mass conservation, where the total mass of the reactants equals the total mass of the products. This law is supported by experimental evidence and is a fundamental principle in chemistry. Choice A, the Law of Conservation of Energy, is incorrect because it pertains to the conservation of energy, not mass. Choice C, the Law of Constant Composition, is incorrect as it refers to compounds having fixed ratios of elements. Choice D, the Law of Multiple Proportions, is incorrect because it describes the ratios in which elements combine to form different compounds, not the conservation of mass.

Correct Answer: B

Rationale: The correct answer is B: Neutron. Beta radiation is the product of the decomposition of a neutron undergoing beta decay. During beta decay, a neutron decays into a proton, an electron (beta particle), and an antineutrino. This process results in the emission of beta radiation. Choice A: Proton is incorrect because beta decay does not involve the decomposition of a proton. Choice C: Electron is incorrect because beta decay actually involves the emission of an electron. Choice D: Photon is incorrect because beta decay results in the emission of beta particles (electrons) and not photons.

Correct Answer: B

Rationale: The sum of protons and neutrons in an element represents the mass number. Protons and neutrons are located in the nucleus and contribute to the mass of an atom. The atomic number (A) is the number of protons in an atom, not the sum of protons and neutrons. Atomic mass (C) is the average mass of an element's isotopes, considering their abundance, and is not the sum of protons and neutrons. Neutron number (D) refers to the specific number of neutrons in an atom, not the total mass of the nucleus. Therefore, the correct answer is B, as it accurately represents the total mass of an atom.

Correct Answer: C

Rationale: The columns of the periodic table are called "Groups" because elements within the same group share similar chemical properties due to having the same number of valence electrons. Each group is designated by a number and a letter, indicating the number of valence electrons. Periods refer to the rows of the periodic table, representing the number of electron shells an element has. Families is a more colloquial term used to describe groups of elements with similar properties. Rows refer to the horizontal rows of the periodic table. Therefore, the correct answer is C as it specifically refers to the vertical columns in the periodic table that share similar chemical properties.