1. unit 1
1.1. lesson 1
1.1.1. Matter Matter is anything that takes up space and can be weighed. In other words, matter has volume and mass. There are many different substances, or types of matter, in the universe.
1.1.2. Solid State Solid state refers to electronic circuits composed of transistors, resistors, capacitors and other components, which may be discrete, single devices, or millions of them can be created in a single chip.
1.1.3. Liquid State In a liquid state of matter, particles are less tightly packed as compared to solids. Liquids take the shape of the container in which they are kept. Liquids are difficult to compress as particles have less space between them to move. Liquids have fixed volume but no fixed shape.
1.1.4. Gas State: A state of matter characterized by particles that are widely spaced and have high kinetic energy, allowing them to move freely and fill the container they are in.
1.1.5. Kinetic Energy: The energy an object possesses due to its motion. It depends on the mass and velocity of the object.
1.1.6. Temperature: A measure of the average kinetic energy of the particles in a substance. It is typically measured in degrees Celsius (°C) or Kelvin (K).
1.1.7. Thermometer: A device used to measure temperature by utilizing a temperature-dependent physical property, such as the expansion of a liquid or gas.
1.1.8. Kelvin Scale: A temperature scale that starts from absolute zero (-273.15°C) and is commonly used in scientific measurements, with temperatures measured in Kelvins (K).
1.1.9. Potential Energy: The stored energy an object possesses due to its position or state, such as gravitational potential energy or chemical potential energy.
1.1.10. Thermal Energy: The total kinetic energy of the particles in a substance, including both their translational and vibrational motion.
1.1.11. Atoms: The basic units of matter, consisting of a nucleus (protons and neutrons) surrounded by electrons.
1.1.12. Substances: Materials that have a distinct chemical composition and specific properties.
1.1.13. Elements: Pure substances consisting of only one type of atom, each represented by a unique chemical symbol.
1.1.14. Compound: A substance formed when two or more different elements chemically combine in fixed ratios.
1.1.15. Molecule: A group of two or more atoms bonded together, either of the same or different elements.
1.1.16. Periodic Table of Elements: A tabular arrangement of all known chemical elements, organized by their atomic number and chemical properties.
1.1.17. Element Symbols: Abbreviations or one- or two-letter codes used to represent chemical elements (e.g., H for hydrogen, O for oxygen).
1.1.18. Chemical Formula: A notation that represents the composition of a compound, indicating the types and numbers of atoms present (e.g., H2O for water).
1.2. lesson 2
1.2.1. Jacques Charles: Jacques Charles was a French scientist known for Charles's Law, which describes the relationship between the volume and temperature of a gas when pressure and the amount of gas are held constant.
1.2.2. Volume-Temperature Law (Charles's Law): Charles's Law states that, at constant pressure and amount of gas, the volume of a gas is directly proportional to its absolute temperature (measured in Kelvins).
1.2.3. Thermal Contraction: The decrease in volume or size of a substance when it is cooled or subjected to lower temperatures.
1.2.4. Systems: In the context of thermodynamics, systems refer to the specific portion of the universe under study, often separated from the surroundings for analysis.
1.2.5. Heating: The process of adding heat energy to a substance or system, usually resulting in an increase in temperature.
1.2.6. Pressure: The force exerted per unit area on a surface. It is typically measured in units such as Pascals (Pa) or atmospheres (atm).
1.2.7. Phase Change: The transition of a substance from one physical state (solid, liquid, gas) to another due to changes in temperature and/or pressure.
1.2.8. Melting: The phase change from a solid to a liquid when a substance is heated to its melting point.
1.2.9. Freezing: The phase change from a liquid to a solid when a substance is cooled to its freezing point.
1.2.10. Condensation: The phase change from a gas to a liquid, typically occurring when a gas is cooled.
1.2.11. Vaporization: The phase change from a liquid to a gas, which includes both boiling and evaporation.
1.2.12. Boiling vs. Evaporation: Boiling is a rapid vaporization process that occurs when a liquid is heated to its boiling point throughout the bulk of the liquid. Evaporation is a slower process in which molecules at the liquid's surface change to the gas phase, typically at temperatures below the boiling point.
1.3. lesson 3
1.3.1. Robert Boyle: Robert Boyle was an Irish natural philosopher, chemist, and physicist of the 17th century. He is best known for Boyle's Law and his contributions to the field of chemistry and the scientific method.
1.3.2. Boyle's Law - Pressure and Volume: Boyle's Law is an experimental gas law that describes the inverse relationship between the pressure and volume of a gas at a constant temperature. Mathematically, it can be expressed as:
1.3.3. Boyle's Law - Number of Particles: Boyle's Law, as originally formulated, primarily deals with the relationship between pressure and volume while keeping the number of gas particles (moles) and temperature constant.
1.3.4. Boyle's Law - Pressure and States of Matter: Boyle's Law applies to gases and is most relevant to gases that behave ideally, meaning they follow the ideal gas law under specific conditions. In the context of states of matter, Boyle's Law helps explain how the volume of a gas changes as pressure is altered while temperature and the number of gas particles remain constant.
1.4. lesson 4
1.4.1. Molecules: Molecules are the smallest units of a chemical compound that can exist independently and retain the chemical properties of that compound. They are composed of two or more atoms bonded together.
1.4.2. Nonmetal Gases: Nonmetals are elements on the periodic table that typically lack metallic properties. Nonmetal gases refer to nonmetallic elements that exist in a gaseous state at standard temperature and pressure (STP), such as oxygen (O2) and nitrogen (N2).
1.4.3. Nonmetal Solids: Nonmetal solids are solid forms of nonmetallic elements or compounds made up primarily of nonmetals. Examples include sulfur (S8) and carbon in its graphite form.
1.4.4. Metals: Metals are elements on the periodic table that are typically characterized by their luster, malleability, electrical conductivity, and high melting and boiling points. They tend to lose electrons and form positively charged ions (cations) in chemical reactions.
1.4.5. Ionic Compounds: Ionic compounds are chemical compounds composed of positively charged ions (cations) and negatively charged ions (anions) held together by electrostatic attraction. They typically involve the transfer of electrons between atoms.
1.4.6. Covalent Compounds: Covalent compounds are chemical compounds in which atoms share electrons to form covalent bonds. These compounds often consist of nonmetals and can be solids, liquids, or gases.
1.4.7. Polar Covalent Compounds: Polar covalent compounds are covalent compounds in which electrons are shared unevenly between atoms, creating partial positive and negative charges within the molecule. This results in a separation of electric charge, making one end of the molecule slightly more positive and the other slightly more negative.
1.4.8. Nonpolar Covalent Compounds: Nonpolar covalent compounds are covalent compounds in which electrons are shared evenly between atoms, resulting in a molecule with no significant separation of electric charge.
1.4.9. Dissolving: Dissolving is the process in which a substance (called the solute) mixes uniformly with another substance (called the solvent) to form a homogeneous mixture known as a solution. It involves the breaking of intermolecular forces in the solute and the formation of new interactions with the solvent molecules.
2. unit 2
2.1. lesson 1
2.1.1. Qualitative Characteristics defination: Qualitative characteristics are the attributes that make financial information useful to users.
2.1.2. Quantitative Characteristics a measurable phenotype that depends on the cumulative actions of many genes and the environment
2.1.3. Mass: Mass is a measure of the amount of matter in an object. It is typically expressed in units such as grams or kilograms. Mass is a fundamental property of an object and remains constant regardless of its location in the universe.
2.1.4. Weight: Weight is the force exerted on an object due to gravity. It is the product of an object's mass and the acceleration due to gravity. Weight varies depending on the gravitational field strength of a particular location. The standard unit for weight is the newton (N).
2.1.5. Volume: Volume refers to the amount of space occupied by an object or substance in three-dimensional space. It is often measured in units such as cubic meters, liters, or milliliters. The volume of an object can change based on its shape and the conditions in which it is placed.
2.1.6. Density: Density is a measure of how much mass is contained in a given volume. It is calculated by dividing an object's mass by its volume. The standard unit for density in the International System of Units (SI) is kilograms per cubic meter (kg/m³). Substances with higher density have more mass in a given volume, while those with lower density have less.
2.1.7. Chemical Properties: Chemical properties are characteristics of a substance that describe how it interacts with other substances or undergoes chemical changes. These properties include reactivity with other chemicals, acidity or basicity (pH), combustion behavior, and its ability to form chemical bonds.
2.1.8. Flammability: Flammability is a chemical property that indicates how easily a substance can ignite and sustain combustion when exposed to a flame, heat, or an ignition source. Substances with high flammability are more prone to catching fire, while those with low flammability are less likely to burn.
2.1.9. Oxidation: Oxidation is a chemical reaction in which a substance loses electrons, often resulting in the addition of oxygen or the removal of hydrogen. It is commonly associated with the rusting of metals and the browning of fruits when exposed to air. Oxidation reactions can be essential in various chemical processes.
2.1.10. Reactivity: Reactivity is a chemical property that describes how readily a substance will undergo chemical reactions with other substances. Highly reactive materials tend to react quickly and vigorously, while less reactive substances may require specific conditions or react slowly.
2.1.11. Solubility: Solubility is a measure of how well a substance can dissolve in a particular solvent at a given temperature and pressure. It is typically expressed as the amount of solute that can dissolve in a specified amount of solvent to form a saturated solution. Solubility can vary widely for different substances and solvents.
2.2. lesson 2
2.2.1. Chemical Changes: Chemical changes, also known as chemical reactions, refer to processes in which one or more substances are transformed into new substances with different chemical properties. These changes often involve the breaking and forming of chemical bonds.
2.2.2. Chemical Reactions: Chemical reactions are processes in which reactants (starting substances) are converted into products (resulting substances) through the rearrangement of atoms and the breaking and forming of chemical bonds. Chemical Equations:
2.2.3. Chemical Equations: Chemical equations are symbolic representations of chemical reactions. They use chemical formulas and symbols to depict the reactants on the left side of the equation and the products on the right side, showing the stoichiometry (mole ratios) of the substances involved.
2.2.4. products: Products are the substances that are formed as a result of a chemical reaction. They appear on the right side of a chemical equation.
2.2.5. Reactants: Reactants are the initial substances that participate in a chemical reaction. They appear on the left side of a chemical equation.
2.2.6. Coefficients: Coefficients in a chemical equation are the numerical values that indicate the relative proportions of reactants and products. They are used to balance chemical equations, ensuring that the number of atoms of each element is conserved.
2.2.7. Antoine Lavoisier: Antoine Lavoisier (1743-1794) was a French chemist who is often referred to as the "Father of Modern Chemistry." He made significant contributions to the understanding of chemical reactions and is credited with the development of the law of conservation of mass.
2.2.8. The law of conservation: The law of conservation of mass, formulated by Antoine Lavoisier, states that in a closed system, the total mass of substances before a chemical reaction is equal to the total mass of substances after the reaction. This fundamental principle implies that mass is neither created nor destroyed during a chemical reaction.
2.2.9. Atomic Mass: Atomic mass refers to the mass of an individual atom of an element, typically measured in atomic mass units (amu) or unified atomic mass units (u). It is a fundamental property of elements and is used to calculate the molar mass of substances in chemistry.
2.3. lesson 3
2.3.1. Chemical Potential Energy: Chemical potential energy is a form of potential energy stored within the chemical bonds of molecules and atoms. It is the energy that can be released or absorbed during a chemical reaction. This energy is associated with the arrangement of particles within a chemical system and can be converted into other forms of energy, such as heat or work, during chemical reactions.
2.3.2. Endothermic Reaction: An endothermic reaction is a chemical reaction that absorbs heat from its surroundings. In these reactions, the products of the reaction have a higher internal energy than the reactants. As a result, the temperature of the surroundings typically decreases, and the reaction feels cold to the touch.
2.3.3. Exothermic Reaction: An exothermic reaction is a chemical reaction that releases heat into its surroundings. In these reactions, the products of the reaction have lower internal energy than the reactants. As a result, the temperature of the surroundings typically increases, and the reaction feels warm or hot to the touch.
2.3.4. Concentration in Reactions: Concentration in chemical reactions refers to the amount of a substance (usually a reactant) present in a given volume or space. It is typically expressed as the number of moles of a substance per unit volume (e.g., moles per liter). Changes in concentration can affect the rate and extent of chemical reactions, especially in reactions involving multiple reactants.
2.3.5. Law of Conservation of Energy: The law of conservation of energy is a fundamental principle in physics and chemistry. It states that energy cannot be created or destroyed in an isolated system; rather, it can only change from one form to another or be transferred between objects. In other words, the total energy of an isolated system remains constant over time. This law is often summarized as "energy is neither created nor destroyed, only converted."