Science Laboratory Rules - Educational Presentation PDF

CHEMISTRY  LEARNING OBJECTIVES At the end of the discussion, students should be able to: 1 2 3 Understand the Learn about the Explore the definition and key discoveries various branches importance of and people in...

CHEMISTRY  LEARNING OBJECTIVES At the end of the discussion, students should be able to: 1 2 3 Understand the Learn about the Explore the definition and key discoveries various branches importance of and people in of chemistry and chemistry in the history of their real-world everyday life. chemistry. applications.  CHEMISTRY the branch of science that deals with the identification of the substances of which matter is composed; the investigation of their properties and the ways in which they interact, combine, and change; and the use of these processes to form new substances. HISTORY OF CHEMISTRY Began to develop rapidly in the 1700s The history of chemistry can be traced back to ancient times, when humans began to record and experiment with materials and metals. The field has evolved through several stages, including alchemy, traditional chemistry, and modern chemistry:  ANTOINE LAVOISIER Antoine Lavoisier (1743–1794) was a French chemist whose contributions revolutionized the field of chemistry and laid the foundation for modern science. Known as the father of modern chemistry,  WHY IS HE THE FATHER OF CHEMISTRY? Contributions: Establishing the law of conservation of mass Naming elements ( Oxygen and Hydrogen) Developing chemical nomenclature MATTER  LEARNING OBJECTIVES At the end of the discussion, students should be able to: 1 1 What is matter? What 2 3 3 what composes the matters with matter? building blocks of matter? How did the conception of How does the structure 2 the atom evolve 4 of the atom look like?  MATTER Matter is anything that takes up space and can be weighed. In other words, matter has volume and mass. There are 3 states of matter: Solids Liquids Gases  SOLIDS Molecular arrangement: Ordered Fixed position, where particles are very close to each other. Appearance and ability to flow: Hard, Rigid, does not flow Volume: Fixed volume and shape. Compressibility: Not easily compressib;e Ability to diffuse: Extremely slow rate of diffusion within the solid.  LIQUIDS Molecular arrangement: Disordered arrangement , particles are free to move and are somewhat close to each other. Appearance and ability to flow: Flows easily Volume: Definite volume: assumes the shape of the continer  LIQUIDS Compressibility: Not easily compressib;e Ability to diffuse: Slow rate of diffusion within the liquid  GASES Molecular arrangement: Very disordered arrangement that are far apart, where they move freely in the empty space Appearance and ability to flow: Flows easily Volume: No fixed Volume, assumes the volume and shape of the container. Compressibility: Easily compressible Ability to diffuse: Fast rate of diffusion within the gas.  PHYSICAL CHANGES IN MATTER PHYSICAL CHANGE a change in which no new material forms. It does not change the kind of matter an object is made up of. Like most physical changes, a change in state can be reversed. EVAPORATION- A process in which liquid turns to gas. (ex.water drying up on a hot day) CONDENSATION- When a gas turns into a liquid as it cools down. (ex. water droplets forming on a cold glass) MELTING- When a solid turns into a liwuid because of heat. (ex. Ice turning into water when heated) FREEZING- When a liquid turns into a solid by cooling down. (ex. water turning into ice in the freezer) PROPERTIES OF MATTER  PHYSICAL PROPERTIES Physical properties are characteristics of matter that can be observed or measured without changing the substance. Examples: Color, shape, size, texture, density, melting point  INTENSIVE PROPERTIES Intensive properties do not depend on the amount of substance present. Examples: Color (The color of a small piece of iron is the same as a large piece). Density (The density of water is the same no matter how much you have). Boiling Point (Water boils at 100°C no matter the quantity).  PHYSICAL CHANGE A physical change is a change in the appearance or state of matter without changing its chemical composition. Examples: Melting ice (Ice turns to water, but it’s still H2O). Tearing paper (The paper is still paper, just in smaller pieces).  EXTENSIVE PROPERTIES Extensive properties depend on the amount of matter or substance present. Examples: Mass (A bigger object has more mass). Volume (The more water you have, the larger the volume). Energy (More energy is needed to heat a larger amount of substance).  CHEMICAL PROPERTY Chemical properties describe how a substance reacts with other substances to form new substances. A chemical reaction occurs wherein reactants form into products or new substances. EXAMPLES OF INTENSIVE AND EXTENSIVE PROPERTIES VISUAL CONCEPTION OF THE CLASSES OF MATTER ELEMENTS are pure substances that cannot be broken down into simpler substances. Examples: Oxygen (O), Hydrogen (H), Carbon (C). COMPOUNDS Are substances made up of two or more different elements chemically combined. LAW OF DEFINITE PROPORTION Proposed by Joseph Proust in 1799. states that a compound is always made of the same elements in the same ratio by mass, no matter the amount or source. Example: Water (H₂O) always has 2 parts hydrogen and 1 part oxygen by mass. NOTE: Compounds can be classified as acids, bases, and salts. To identify one from the others you need to use INDICATORS. ( substances whose colors are affected by acids and bases)  MIXTURE A mixture is a combination of two or more substances that are not chemically combined and can be separated by physical methods. HOMOGENEOUS MIXTURE appears as one uniform phase of matter HETEROGENOUS MIXTURE not uniformly mixed THANK YOU! I hope you learned something new today!