Chemistry HESI A2 Quizlet

Correct Answer: A

Rationale: The correct answer is A: Hydrogen and oxygen. Water decomposes into hydrogen and oxygen through a process called electrolysis. In this process, an electric current is passed through water, causing it to break down into its constituent elements. Hydrogen is produced at the cathode, while oxygen is produced at the anode. This is a well-known and scientifically proven reaction. Choices B, C, and D are incorrect because water does not decompose into carbon dioxide, nitrogen, or methane under normal conditions. This can be confirmed by studying the chemical properties and reactions of water.

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: A

Rationale: The correct answer is A: Periods. Periods are the horizontal rows in the periodic table that represent the number of electron shells an element has. Each period corresponds to the principal energy level of the element. Families (Choice B) are the vertical columns of the periodic table that share similar properties. Groups (Choice C) are also vertical columns that share similar chemical properties. Columns (Choice D) are not a term used in the context of the periodic table. Therefore, the correct term for the horizontal rows in the periodic table is periods.

Correct Answer: A

Rationale: Certainly! The correct answer is A: Radioactivity. Radioactivity refers to the emission of particles from an unstable nucleus due to nuclear instability. This process can include alpha, beta, or gamma decay. Choice B, Radiation, is a more general term that encompasses various types of energy emission, not specific to nuclear decay. Choice C, Decay, is a broader term and does not specify the emission from a nucleus. Choice D, Fusion, involves combining nuclei to form a heavier nucleus, not the emission of particles from an unstable nucleus.

Correct Answer: C

Rationale: The correct answer is C: +2. Alpha radiation particles are helium nuclei consisting of 2 protons and 2 neutrons, giving them a charge of +2. This charge is due to the presence of 2 protons, which are positively charged particles. Choice A (-2) is incorrect as alpha particles are positively charged. Choice B (0) is incorrect as alpha particles have a positive charge. Choice D (+1) is incorrect as alpha particles have a charge of +2 due to the presence of 2 protons.