The Nucleus

Who proposed the atomic theory in 1905?

• Isaac Newton

• Niels Bohr

• Albert Einstein

• Marie Curie

What is atomic weight?

• The total number of protons in an atom.

• The average mass of an element's atoms, measured in atomic mass units (amu), reflecting the relative abundance of isotopes.

• The mass of an atom's nucleus only.

• The weight of an atom in grams.

What is the charge of a neutron?

• Positive charge

• Negative charge

• No charge; it is neutral.

• Variable charge depending on the environment

What is the nucleus?

• The nucleus is the central part of an atom, containing protons and neutrons, and is responsible for the atom's mass and positive charge.

• The nucleus is a part of the cell that contains the cell's genetic material.

• The nucleus is a type of subatomic particle found in the electron cloud.

• The nucleus is the outer layer of an atom that contains electrons.

What is the concept of atomic stability?

• Atomic stability refers to the balance of forces within the nucleus; stable nuclei have a favorable ratio of protons to neutrons.

• Atomic stability is the ability of an atom to resist changes in its electron configuration.

• Atomic stability is the measure of an atom's ability to conduct electricity.

• Atomic stability refers to the energy released during nuclear fission.

What is the charge of a proton?

• +1 elementary charge

• -1 elementary charge

• 0 elementary charge

• +2 elementary charge

What is the difference between atomic number and mass number?

• The atomic number is the number of protons in the nucleus, while the mass number is the total number of protons and neutrons.

• The atomic number is the total number of neutrons, while the mass number is the number of protons in the nucleus.

• The atomic number is the sum of protons and neutrons, while the mass number is the number of electrons.

• The atomic number is the number of electrons in an atom, while the mass number is the number of protons and neutrons.

What is the relationship between the number of protons and electrons in a neutral atom?

• In a neutral atom, the number of protons equals the number of electrons, balancing the overall charge.

• In a neutral atom, the number of protons is greater than the number of electrons.

• In a neutral atom, the number of electrons is greater than the number of protons.

• In a neutral atom, protons and electrons are unrelated.

What is the role of neutrons in the nucleus?

• Neutrons contribute to the mass of the nucleus and help stabilize it by offsetting the repulsive forces between protons.

• Neutrons are responsible for the chemical properties of an atom.

• Neutrons determine the atomic number of an element.

• Neutrons are involved in the formation of covalent bonds.

How do isotopes of an element differ?

• Isotopes of an element have the same number of protons but different numbers of neutrons, resulting in different mass numbers.

• Isotopes of an element have different numbers of protons and the same number of neutrons.

• Isotopes of an element have the same mass number but different atomic numbers.

• Isotopes of an element are chemically identical but have different electron configurations.