Chemistry HESI A2 Quizlet

Correct Answer: C

Rationale: Alpha particles are positively charged and relatively large, so they have low penetrating power. A piece of paper can stop alpha particles because the paper's thickness provides enough material for the particles to collide with and lose their energy through ionization. Aluminum foil and glass are not thick enough to effectively stop alpha particles. Plastic, depending on its thickness, may not provide sufficient shielding to stop alpha particles completely. In summary, the correct answer is C because the thickness of a piece of paper is sufficient to stop alpha particles, while the other choices are not adequate for effective shielding.

Correct Answer: C

Rationale: The correct answer is C: Gamma. Gamma radiation is high-energy electromagnetic radiation with no charge or mass, making it able to penetrate matter easily. Beta (A) and Alpha (B) radiation are particles with charge and mass, and Delta (D) is not a type of radiation. Therefore, Gamma is the only option that fits the given characteristics.

Correct Answer: A

Rationale: The correct answer is A: Neutrons. Neutrons are neutral particles because they have no charge, unlike protons (positively charged), electrons (negatively charged), and cations (positively charged ions). Neutrons are found in the nucleus of an atom along with protons, contributing to the atomic mass without affecting the overall charge. This makes them essential for maintaining the stability of the nucleus. Therefore, neutral particles are called neutrons.

Correct Answer: B

Rationale: The correct answer is B: Chemical reaction. In a chemical reaction, bonds are broken and new bonds are formed to create new chemical compounds. The process involves the rearrangement of atoms to form different substances with unique properties. Physical reactions (choice A) involve changes in physical state or appearance without altering the chemical composition. Nuclear reactions (choice C) involve changes in the nucleus of an atom, leading to the formation of different elements. Mechanical reactions (choice D) involve physical forces but do not result in the formation of new chemical compounds.

Correct Answer: C

Rationale: The correct answer is C: Radiation. During radioactivity, particles such as alpha and beta particles, gamma rays, and positrons are emitted. These particles are collectively known as radiation. Electrons (choice A) and protons (choice B) are subatomic particles found in atoms and are not typically emitted during radioactivity. Neutrons (choice D) are neutral subatomic particles and are not emitted during radioactivity. Therefore, the correct answer is C as it encompasses the various types of particles emitted during radioactive decay.