Fundamental Concepts of Chemistry Quiz

Matter
- Definition: Anything that has mass and occupies space.
- States: Solid, Liquid, Gas, Plasma.
Atoms
- Basic unit of matter.
- Consists of protons, neutrons, and electrons.
- Atomic number = number of protons.
- Atomic mass = protons + neutrons.
Elements
- Pure substances that cannot be broken down.
- Organized in the Periodic Table.
- Each element has a unique atomic symbol.
Compounds
- Substances formed from two or more elements chemically bonded.
- Has a specific formula (e.g., H₂O, CO₂).

Types of Reactions
- Synthesis: A + B → AB
- Decomposition: AB → A + B
- Single Replacement: A + BC → AC + B
- Double Replacement: AB + CD → AC + BD
- Combustion: Hydrocarbon + O₂ → CO₂ + H₂O
Balancing Equations
- Law of Conservation of Mass: Mass is conserved in a chemical reaction.
- Coefficients are used to balance equations.

Solids
- Fixed shape and volume, particles closely packed.
Liquids
- Fixed volume but takes the shape of the container, particles less tightly packed.
Gases
- No fixed shape or volume, particles far apart and move freely.

Solutions
- Homogeneous mixtures of solute and solvent.
Concentration
- Measure of the amount of solute in a given volume of solution (e.g., molarity).

Acids
- Substances that donate protons (H⁺ ions).
- Have a pH < 7.
Bases
- Substances that accept protons or donate hydroxide ions (OH⁻).
- Have a pH > 7.
pH Scale
- Ranges from 0 to 14.
- pH = 7 is neutral; < 7 is acidic; > 7 is basic.

Atomic Radius
- Increases down a group; decreases across a period.
Electronegativity
- Tendency of an atom to attract electrons; increases across a period, decreases down a group.
Ionization Energy
- Energy required to remove an electron from an atom; increases across a period, decreases down a group.

Ionic Bonds
- Formed through the transfer of electrons between atoms (e.g., NaCl).
Covalent Bonds
- Formed by the sharing of electrons (e.g., H₂O).
Metallic Bonds
- Attraction between metal ions and delocalized electrons.

Molecules
- Diatomic molecules: Two atoms (e.g., O₂, N₂).
- Polyatomic molecules: More than two atoms (e.g., CO₂, C₆H₁₂O₆).
Nomenclature Rules
- Ionic compounds: Name metal first, followed by non-metal with an -ide suffix.
- Covalent compounds: Use prefixes to denote the number of atoms.

Matter is anything that has mass and occupies space.
Matter exists in four states: solid, liquid, gas, and plasma.
Atoms are the basic building blocks of matter.
Atoms consist of protons, neutrons, and electrons.
The atomic number of an element is determined by the number of protons in its atom.
The atomic mass of an element is calculated by adding the number of protons and neutrons.
Elements are pure substances that cannot be broken down into simpler substances.
Elements are organized in the Periodic Table, with each element having a unique atomic symbol.
Compounds are substances formed when two or more elements chemically bond.
Every compound has a specific formula that describes its composition (for example, H₂O, CO₂).

Chemical reactions involve the rearrangement of atoms and molecules.
Common types of reactions:
- Synthesis: combination of reactants to form a product (A + B → AB)
- Decomposition: breakdown of reactants into simpler products (AB → A + B)
- Single Replacement: one element replaces another in a compound (A + BC → AC + B)
- Double Replacement: exchange of elements between two reactants (AB + CD → AC + BD)
- Combustion: rapid reaction involving a fuel and an oxidizer (typically oxygen) that releases heat and light.
The Law of Conservation of Mass states that mass is conserved in a chemical reaction.
To ensure that mass is conserved, chemical equations must be balanced using coefficients.

Solids have a fixed shape and volume, with particles closely packed.
Liquids have a fixed volume but take the shape of their container; their particles are less closely packed than solids.
Gases have no fixed shape or volume; their particles are widely spaced and move freely.

Solutions are homogeneous mixtures of a solute dissolved in a solvent.
Concentration measures the amount of solute in a given volume of solution.
Molarity is a common unit of concentration that expresses moles of solute per liter of solution.

Acids donate protons (H⁺ ions), have a pH less than 7, and taste sour.
Bases can accept protons or donate hydroxide ions (OH⁻), have a pH greater than 7, and feel slippery.
The pH scale measures acidity and basicity, with a pH of 7 being neutral.

Atomic radius generally increases down a group in the periodic table and decreases across a period.
Electronegativity generally increases across a period and decreases down a group.
Ionization energy generally increases across a period and decreases down a group.

Ionic bonds form between positively and negatively charged ions because of electrostatic attractions (e.g., NaCl).
Covalent bonds form when atoms share electrons to achieve a stable electron configuration (e.g., H₂O).
Metallic bonds form by the attraction between metal ions and delocalized electrons.

Molecules are composed of two or more atoms held together by chemical bonds.
Diatomic molecules consist of two atoms, such as O₂ or N₂.
Polyatomic molecules consist of more than two atoms, such as CO₂ or C₆H₁₂O₆.
Chemical nomenclature provides rules for naming chemical compounds.
Ionic compounds are named with the metal name followed by the non-metal name, with an -ide suffix.
Covalent compounds use prefixes to denote the number of atoms of each element.

Safety gear, such as goggles, gloves, lab coats, and fume hoods, must be worn appropriately in the chemical laboratory.
Hazards related to specific chemicals, such as corrosiveness, flammability, and toxicity, should be identified and understood.
All chemicals should be disposed of according to established procedures.