2024-2025 Chemistry 1- Semester 1 Final

Front

Why is ice melting into water not considered a chemical change?

Back

Because it involves a change in state, not a change in chemical composition.

Front

What is the molecular shape of NH₄⁺?

Back

Tetrahedral

Front

How many valence electrons are in the NH₄⁺ structure?

Back

7

Front

What is a covalent bond?

Back

A covalent bond is formed when two atoms share one or more pairs of electrons with each other.

Front

What is the branch of science that deals with substances containing carbon?

Back

Organic chemistry.

Front

What is the difference between a physical change and a chemical change?

Back

A physical change involves a change in state or appearance without altering the chemical composition, while a chemical change results in the formation of new substances.

Front

What is the octet rule?

Back

The octet rule states that atoms tend to gain, lose, or share electrons to achieve a full outer shell of eight electrons.

Front

What is the significance of valence electrons in chemical bonding?

Back

Valence electrons are the electrons in the outermost shell of an atom and are involved in forming bonds with other atoms.

Front

What is the difference between ionic and covalent bonds?

Back

Ionic bonds involve the transfer of electrons from one atom to another, while covalent bonds involve the sharing of electrons between atoms.

Front

What is a polar covalent bond?

Back

A polar covalent bond is a type of covalent bond where electrons are shared unequally between two atoms, resulting in a molecule with a slight charge.