Exploring Matter and Atoms

What is the difference between a mixture and a solution?

• A solution retains the properties of its components, while a mixture does not.

• A mixture is a type of solution that is always clear.

• A mixture is always a liquid, while a solution can be solid.

• A mixture retains the properties of its components, while a solution is a homogeneous mixture where the solute is dissolved in the solvent.

Define a homogeneous mixture and provide an example.

• Air is a homogeneous mixture.

• Sand is a homogeneous mixture.

• An example of a homogeneous mixture is salt water.

• Oil and water mixed together is a homogeneous mixture.

What is a compound? Give an example of a common compound.

• Water (H2O)

• Oxygen (O2)

• Salt (NaCl)

• Carbon Dioxide (CO2)

How do elements differ from compounds?

• Elements are always solid; compounds can be gases.

• Elements can be made of multiple types of atoms; compounds cannot.

• Elements are formed through chemical reactions; compounds are not.

• Elements consist of one type of atom; compounds consist of two or more different types of atoms.

What is the smallest unit of an element?

• molecule

• atom

• compound

• ion

Describe the structure of an atom.

• An atom consists of a solid core made of electrons and a cloud of protons.

• An atom is a single particle that cannot be divided into smaller parts.

• Atoms are made up entirely of neutrons with no other particles present.

• An atom is structured with a central nucleus containing protons and neutrons, surrounded by electrons in orbitals.

What are protons, neutrons, and electrons?

• Protons are positively charged particles, neutrons are neutral particles, and electrons are negatively charged particles.

• Protons are neutral particles, neutrons are positively charged particles, and electrons are positively charged particles.

• Protons and neutrons are both negatively charged, while electrons are positively charged.

• Protons are negatively charged particles, neutrons are positively charged particles, and electrons are neutral particles.

How is the atomic number of an element determined?

• The atomic number is the sum of neutrons and protons in the nucleus.

• The atomic number is the number of protons in an atom's nucleus.

• The atomic number is determined by the element's position in the periodic table.

• The atomic number is the total number of electrons in an atom.

What is the significance of the mass number?

• The mass number is the measure of an atom's reactivity.

• The mass number represents the atomic mass in grams.

• The mass number indicates the number of electrons in an atom.

• The mass number signifies the total number of protons and neutrons in an atom.

Explain what isotopes are and give an example.

• Isotopes are elements with different atomic numbers, like Oxygen-16 and Oxygen-18.

• An example of isotopes is Carbon-12 and Carbon-14, where both have 6 protons but Carbon-12 has 6 neutrons and Carbon-14 has 8 neutrons.

• An example of isotopes is Helium-3 and Helium-4, which have different numbers of protons.

• Isotopes are always radioactive, such as Uranium-235 and Uranium-238.