Question

2.1 the nature of matter

1. in the atom, which particles are in constant motion around the nucleus?

a. protons
b. protons and neutrons
c. neutrons
d. electrons

1. how do the properties of sodium chloride (nacl) compare with the properties of its component elements, sodium (na) and chlorine (cl)?
2. how do the isotopes of an element differ?
3. describe the electric charges of the three main subatomic particles.

Explanation:

1. In an atom, electrons are in constant motion around the nucleus. Protons and neutrons are in the nucleus.
2. Sodium chloride is a compound with properties different from its component elements. Sodium is a reactive metal and chlorine is a toxic gas, while sodium chloride is a common table - salt, stable and edible.
3. Isotopes of an element have the same number of protons but different numbers of neutrons, resulting in different atomic masses.
4. Protons have a positive charge, electrons have a negative charge, and neutrons have no charge.

Answer:

1. d. electrons
2. Sodium chloride has different properties than sodium and chlorine. Sodium is a reactive metal, chlorine is a toxic gas, while sodium chloride is a stable, edible compound.
3. Isotopes of an element have the same number of protons but different numbers of neutrons and thus different atomic masses.
4. Protons: positive charge; Electrons: negative charge; Neutrons: no charge.