Chemistry of Matter and Atomic Structure

Chemistry of Matter

• Chemistry studies atoms, molecules, their bonding, and reactions.
• Matter is anything with mass and volume.
• A substance is uniform in composition.
• An element is a substance that cannot be broken into simpler substances.
• A compound is formed when two or more elements chemically combine.

Atomic Structure

• Atoms are the fundamental units of matter.
• Atoms consist of electrons, neutrons, and protons.
• Electrons are negatively charged and orbit the nucleus.
• Neutrons are uncharged and found in the nucleus.
• Protons are positively charged and found in the nucleus.
• The number of protons defines an element.

The Periodic Table

• The periodic table organizes elements by properties.
• Elements are arranged in rows (periods) and columns (groups).
• Periods reflect electron shell counts.
• Groups show similar valence electron numbers.
• Metals are on the left side and middle.
• Nonmetals are on the right.
• Noble gases are the last group of nonmetals, unreactive.
• Metalloids have properties between metals and nonmetals.
• Element squares contain information like symbol, atomic number, and atomic mass.

Compounds

• A compound is formed of two or more elements.
• Molecules are the smallest unit of a compound.
• Compounds are identified by their chemical formula that shows the types and ratios of elements.
• Examples: Water (H₂O)

Isotopes and Ions

• Isotopes have a differing number of neutrons.
• Ions are charged atoms.
• Anions are negatively charged ions.
• Cations are positively charged ions.
• Radioactive isotopes are unstable and emit radiation.

Bonding

• Atoms bond to achieve stability (usually an outer shell with eight electrons).
• Lewis electron dot diagrams depict valence electrons.
• Ionic bonds form from electron transfer (cation and anion).
• Covalent bonds result from electron sharing.
• Polar covalent bonds—unequal electron sharing (dipole).
• Nonpolar covalent bonds—equal electron sharing.

States of Matter

• Substances exist as solids, liquids, or gases (phases).
• Phase changes occur with temperature and/or pressure changes.
• Vapor pressure is the tendency to transition to a gas phase.

Mixtures

• Mixtures are physically combined substances.
• Homogeneous mixtures are uniform (solutions).
• Heterogeneous mixtures are non-uniform.

Solutions

• Solutions involve a solute dissolved in a solvent.
• Solubility measures dissolution tendency.
• Solutions can be separated by filtration or distillation.
• Chromatography separates multiple solutes.
• Tinctures are concentrated solutions (alcoholic solvent).
• Emulsions are mixtures of immiscible liquids.

Changes in Matter

• Chemical changes involve bond breaking/forming.
• Physical changes involve no bond breaking/forming.

Chemical Reactions

• Chemical reactions occur when bonds are broken/formed.
• Reactants are initial substances.
• Products are resulting substances.
• Endothermic reactions absorb energy.
• Exothermic reactions release energy.
• Equilibrium is a balance between products and reactants.
• Conservation of mass means the mass is equal before and after a reaction.

Reaction Types

• Synthesis reaction: Two reactants combine to form one product.
• Single replacement reaction: One element replaces another in a compound.
• Double displacement reaction: The elements of two compounds swap.
• Decomposition reaction: A compound breaks down into two or more substances.

Reaction Rate

• Reaction rate is how fast a reaction proceeds.
• Factors influence reaction rates (temperature, pressure, catalysts).

Catalysts

• Catalysts speed up reactions without being consumed.
• They lower the activation energy.

Acid-Base Chemistry

• Acids produce H⁺ ions in solution.
• Bases produce OH⁻ ions in solution.
• The pH scale measures acidity/basicity (0-14).
• Neutralization reactions involve acid and base combining to form water and salt.
• Indicators change color with acid/base.

Chemical Equilibrium

• Reactions continue until equilibrium established.
• The law of conservation of mass applies (equal amounts before/after reaction).

Organic Chemistry Basics

• Organic chemistry studies carbon-containing compounds.
• Carbon forms four bonds and builds complex molecules.

Organic Compounds

• Four main biological molecules make up living things.
• Monomers join to form polymers.
• Each molecule type has a distinct structural formula.

Nucleic Acids

• DNA and RNA are nucleic acids.
• They contain genetic code.
• Nucleotides are the monomers.

Carbohydrates

• Main energy source and structural elements.
• Monosaccharides are simple sugars (e.g., glucose).
• Disaccharides are formed from two monosaccharides.
• Polysaccharides are long chains of monosaccharides (e.g., starch).
• Glycogen is animal carbohydrate storage.
• Indicator solutions for carbohydrates (starch and sugars can be detected and differentiated).

Lipids

• Fats used for energy storage, membranes, insulation, and waterproofing.
• Fatty acids and glycerol are the monomers.

Proteins

• Diverse biomolecules with various functions (hormones, enzymes, antibodies).
• Amino acids are the monomers.
• Biuret solution detects proteins.

Reactions

• Dehydration synthesis (condensation reaction): Joins molecules, releases water.
• Hydrolysis: Breaks down molecules using water.
• Oxidation-Reduction: Gain/loss of electrons.
• Hydrocarbons are carbon and hydrogen compounds.
• Alcohols have hydroxyl groups (-OH).
• Oxidation forms aldehydes/ketones, reduction forms alcohols.

Explore the fundamental concepts of chemistry, including the nature of matter, atomic structure, and the organization of elements in the periodic table. This quiz will assess your understanding of atoms, compounds, and the classification of elements based on their properties.