ATI TEAS 7 I COMPLETE CHEMISTRY REVIEW Part 1 I

This paragraph introduces the concept of matter as anything with mass and volume, occupying space and having weight. It distinguishes matter from forms of energy like light, heat, and sound. The properties of matter, both physical and chemical, are outlined, including color, size, volume, density, and reactivity. The paragraph also explains the states of matter—solid, liquid, and gas—and how molecular spacing and movement affect these states. Phase changes and the influence of temperature and pressure on these changes are discussed, along with heating and cooling curves that illustrate the relationship between temperature and heat absorption or release during phase transitions.

This section delves into the phase changes in more detail, describing the processes of melting, vaporization, sublimation, freezing, condensation, and deposition. It emphasizes the role of heat absorption and release during these changes, as well as the impact on molecular cohesion. The paragraph then transitions to the chemical composition of matter, explaining the difference between pure substances and mixtures, and further distinguishing between elements and compounds. The formation of compounds from elements is illustrated with examples, highlighting the concepts of diatomic elements and their role in compound formation.

The script explores the building blocks of matter, starting with subatomic particles like protons, electrons, and neutrons, and their roles in forming atoms. It describes the atomic nucleus and electron orbitals, then moves on to the periodic table, explaining how elements are unique types of atoms. The concept of diatomic elements is introduced, and the script contrasts them with non-diatomic elements. The paragraph also discusses molecules, which are groups of atoms, and compounds, which are molecules made from different types of atoms. The relationship between these concepts is summarized, and the organization of the periodic table is explained in terms of atomic number, groups, and periods.

This paragraph discusses the categorization of elements based on their properties, focusing on metals, non-metals, and metalloids. It describes the characteristics of metals, such as their luster, conductivity, and malleability, and contrasts these with the properties of non-metals. Metalloids are presented as having properties of both metals and non-metals. The paragraph also explains the concept of ionic and covalent bonds, how they form, and the role of the octet rule in achieving stable electron configurations. The formation of ions and the relationship between atomic structure and charge are also covered, along with the trends of ion formation for different groups of elements.

The script provides a deeper look into the atomic structure, explaining how atoms achieve stability through the loss, gain, or sharing of electrons to form ionic and covalent bonds. It details the process of ionic bond formation between metals and non-metals, resulting in the formation of cations and anions. The concept of electronegativity is introduced to explain the polarity of covalent bonds, with a focus on how the difference in electronegativity values between atoms determines whether a bond is polar or nonpolar. The paragraph also includes examples of how to determine the type of bond between different elements based on their electronegativity values.

This section explains the structure of atoms in terms of energy levels or shells and the role of valence electrons in chemical reactions. It provides a quick reference guide to the number of valence electrons based on the periodic table's periods and groups. The paragraph also discusses the rules for filling electron shells and the concept of isotopes, which are variants of elements with different numbers of neutrons. Isotopes are characterized by their atomic number, mass number, and the number of neutrons, with examples provided to illustrate how to calculate these values.

The script discusses periodic trends observed on the periodic table, focusing on atomic radii and the factors that affect them. It explains how atomic size is influenced by the distance of valence electrons from the nucleus and the number of protons present. The paragraph outlines the trends in atomic radii, noting that they increase from right to left and from top to bottom on the periodic table. It also contrasts the sizes of atoms with different numbers of protons, such as hydrogen and helium, and lithium and neon, to illustrate these trends.

This section delves into the concepts of ionic radii, ionization energy, and electronegativity. It explains how cations are smaller than their neutral atoms due to a stronger pull of protons on electrons, while anions are larger due to additional electrons repelling each other. The ionization energy, the energy required to remove an electron from an atom, is discussed in relation to the periodic table trends, with higher ionization energy associated with atoms that hold their electrons more tightly. Electronegativity, the tendency of an atom to attract electrons, is introduced, with fluorine identified as the most electronegative element. The trends of electronegativity across the periodic table are explained, along with exceptions to these trends.

The script provides an overview of chemical reactions, emphasizing the importance of balancing chemical equations in accordance with the law of conservation of mass. It explains the concept of reactants and products and the process of balancing equations through the adjustment of coefficients. Examples are given to illustrate the trial-and-error process of balancing equations, ensuring equal numbers of atoms of each element on both sides of the equation. The paragraph also introduces the five basic types of chemical reactions: synthesis, decomposition, single displacement, double displacement, and combustion, providing examples and characteristics of each.

This section focuses on identifying acids and bases using the Arrhenius and Bronsted-Lowry theories. The Arrhenius theory defines acids as substances that release hydrogen ions (protons) and bases as those that release hydroxide ions in solution. The Bronsted-Lowry theory characterizes acids as proton donors and bases as proton acceptors. The script provides examples to illustrate these definitions, such as NH3 acting as a base by accepting a proton, and H2O acting as an acid by donating a proton. The concept of conjugate acids and bases is also introduced, highlighting the reversible nature of proton transfer in weak acid-base reactions.

The script concludes with an explanation of the pH scale, which measures the acidity or basicity of a solution. It describes the pH scale's relationship with the concentration of hydronium (hydrogen) ions and hydroxide ions, with values below 7 indicating acidity, above 7 indicating basicity, and a neutral pH of 7. Examples using hydrochloric acid and sodium hydroxide illustrate how strong acids and bases dissociate completely in solution, leading to high concentrations of hydronium or hydroxide ions, respectively. The paragraph also touches on the reversibility of weak acids and bases and their partial dissociation in solution.