Chemistry Midterm Review 2023

Front

What happens to a substance when it loses energy?

Back

The substance typically undergoes a phase change, such as from gas to liquid or liquid to solid, resulting in a decrease in temperature and kinetic energy.

Front

What is Hund's Rule?

Back

Hund's Rule states that electrons will fill degenerate orbitals (orbitals of the same energy) singly before pairing up, to minimize electron-electron repulsion.

Front

What is the Pauli Exclusion Principle?

Back

The Pauli Exclusion Principle states that no two electrons in an atom can have the same set of four quantum numbers, meaning that an orbital can hold a maximum of two electrons with opposite spins.

Front

Why does atomic radius decrease across a period in the periodic table?

Back

As you move from left to right across a period, the number of protons in the nucleus increases, which increases the positive charge and pulls the electrons closer, resulting in a smaller atomic radius.

Front

Which element has the largest atomic radius in Group 18?

Back

Radon (Rn) has the largest atomic radius in Group 18.

Front

What are the characteristics of a solid state of matter?

Back

A solid has a definite volume and a definite shape due to closely packed particles that vibrate in place.

Front

What is the significance of the atomic number?

Back

The atomic number represents the number of protons in an atom's nucleus and determines the element's identity.

Front

What is the difference between an ionic bond and a covalent bond?

Back

An ionic bond is formed when electrons are transferred from one atom to another, resulting in charged ions, while a covalent bond is formed when two atoms share electrons.

Front

What is the role of valence electrons in chemical bonding?

Back

Valence electrons are the outermost electrons of an atom and are involved in forming bonds with other atoms, determining the atom's reactivity.

Front

What is a chemical reaction?

Back

A chemical reaction is a process in which substances (reactants) are transformed into different substances (products) through the breaking and forming of chemical bonds.