Chemistry for ATI TEAS Version 7

Overview:

• Chemistry is a key component of the ATI TEAS Version 7 Science test.
• Focuses on atomic structure, chemical reactions, properties of matter, solutions, and acids/bases.

Basic Atomic Structure:

• Atoms: Consist of a nucleus containing protons and neutrons; electrons orbit the nucleus.
  • Protons: Positively charged particles.
  • Neutrons: Particles with no charge.
  • Electrons: Negatively charged particles, much smaller than protons.
• Isotopes: Atoms of the same element with different numbers of neutrons.
• Atomic Mass: Sum of protons and neutrons.
• Atomic Number: Number of protons in an atom.
• Ions: Atoms that have gained or lost electrons, resulting in a charge.
  • Cations: Positively charged ions (lost electrons).
  • Anions: Negatively charged ions (gained electrons).

Periodic Table of Elements:

• Organized by increasing atomic number.
• Groups: Columns indicating the number of valence electrons.
• Periods: Rows indicating the number of orbitals.
• Valence Electrons: Electrons in the outermost shell, important for chemical reactions.

Types of Chemical Bonds:

• Ionic Bonds: Atoms trade electrons, forming charged ions.
• Covalent Bonds: Atoms share electrons.
• Electronegativity: Determines the type of bond formed.

Physical Properties of Matter:

• Mass, Volume, Density: Key physical properties.
• States of Matter: Solid, liquid, gas, plasma.
• Phase Changes: Condensation, evaporation, sublimation, deposition, melting, freezing.

Chemical Reactions:

• Valence Electrons: Determine reactivity and type of bonds formed.
• Chemical Equations: Symbolic representation of chemical reactions.
  • Reactants and Products: Substances before and after the reaction.
• Balancing Equations: Ensuring equal number of each type of atom on both sides.
• Moles: Measure the amount of substance for reactions.

Reaction Conditions:

• Endothermic Reactions: Absorb heat.
• Exothermic Reactions: Release heat.
• Chemical Equilibrium: Balance between forward and reverse reactions.
• Catalysts: Speed up reactions, lower activation energy.

Properties of Solutions:

• Polarity of Water: Polar molecule with hydrogen bonds.
• Solvents and Solutes: Solvent dissolves solute; water is a universal solvent.
• Concentration and Dilution: Measure of solute in solvent.
• Osmosis and Diffusion: Movement of water and molecules, respectively.

Acids and Bases:

• Acids: Increase hydrogen ion concentration.
• Bases: Decrease hydrogen ion concentration.
• pH Scale: Measures acidity or basicity (0-14 scale).
• Buffers: Resist changes in pH.
• Neutralization Reactions: Between an acid and a base, producing water and salt.