What are negatively charged ions called?

Correct Answer: C

Rationale: Negatively charged ions are called anions. Anions gain electrons and carry a negative charge, which distinguishes them from cations that are positively charged and neutrons and protons that are subatomic particles found in the nucleus of an atom. Choice A, Neutrons, are neutral subatomic particles found in the nucleus of an atom, not negatively charged ions. Choice B, Protons, are positively charged subatomic particles found in the nucleus of an atom, not negatively charged ions. Choice D, Cations, are positively charged ions that lose electrons, which is opposite to the behavior of negatively charged ions.

Correct Answer: C

Rationale: The correct answer is C: Atomic number. The atomic number corresponds to the number of protons in an element. Protons are positively charged subatomic particles found in the nucleus of an atom. Each element has a unique atomic number, which defines its identity based on the number of protons it contains. Choice A, Atomic mass, is incorrect as it refers to the average mass of an atom of an element. Choice B, Mass number, represents the total number of protons and neutrons in an atom's nucleus. Choice D, Proton number, is not a commonly used term in chemistry to indicate the number of protons.

Correct Answer: B

Rationale: The sum of protons and neutrons in an element is known as the mass number. The mass number is an important concept in chemistry as it represents the total number of nucleons (protons and neutrons) in an atom's nucleus. It is different from the atomic number, which represents the number of protons in an atom. The atomic mass is the average mass of an element's isotopes, taking into account the abundance of each isotope. Neutron number, on the other hand, specifically refers to the number of neutrons in an atom's nucleus. Therefore, the correct answer is B, mass number.

Correct Answer: A

Rationale: In a chemical reaction, atoms interact to achieve stable electron configurations through the formation of new chemical bonds or the breaking of existing ones. This process aims to reach a more stable state by filling or emptying electron orbitals, leading to the formation of new substances with more stable configurations. Choice B, nuclear reactions, involve changes in the atomic nucleus rather than electron configurations. Choice C, physical reactions, involve changes in physical state or appearance without changing the chemical makeup. Choice D, mechanical reactions, do not involve the rearrangement of electrons to achieve stable configurations.

Correct Answer: B

Rationale: Nuclear reactions occur within the nucleus to achieve stable nuclear configurations. These reactions involve changes in the composition of atomic nuclei, leading to the formation of more stable elements. Chemical reactions occur in the electron cloud surrounding the nucleus, while physical and mechanical processes do not directly impact the stability of nuclear configurations. Therefore, the correct answer is 'Nuclear.'