Batterjee Medical College Chapter 1 Matter & Changes PDF

Chapter 1 MATTER & CHANGES Edited by Dr. Nazar Abdulaziz Elnasri Chemistry department –BMC asser-2024/2025 1 Content 2 1.1. Description of Matter Matter is the term for any type of material that has mass and volume. Matter is every...

Chapter 1 MATTER & CHANGES Edited by Dr. Nazar Abdulaziz Elnasri Chemistry department –BMC asser-2024/2025 1 Content 2 1.1. Description of Matter Matter is the term for any type of material that has mass and volume. Matter is everything around you. Atoms, molecules, wood, and metals are all classified as matter. There are three basic states of matter: solid, liquid, and gas. Loading… 3  STATES OF MATTER SOLIDS Particles of solids are tightly packed, vibrating about a fixed position. Solids have a definite shape and a definite volume. Give examples of solid ? Heat 4 1.4. States (Phases) of Matter Solids Solids can be crystalline or amorphous. Loading… 5 STATES OF MATTER LIQUID Particles of liquids are tightly packed, but are far enough apart to slide over one another. Liquids have an indefinite shape and a definite volume. Give examples of liquid? Heat 6  Particles of gases are very far apart and move freely. STATES OF MATTER GAS Gases have an indefinite shape and an indefinite volume. Give examples of gas? Heat 7 Classification of matter Matter Has mass and takes up space Substance Mixture Compound Homogeneous Heterogeneous Element Two or more Evenly mixed Unevenly mixed One kind of kinds of atoms atom 8 Elements and Compounds Elements are substances that are made of one kind of atoms. Examples: hydrogen (H2), carbon (C), oxygen (O2), and nitrogen (N2). Compounds are substances that made of two or more different atoms chemically combined together. Compounds can be broken down into simpler substances only by chemical methods example: pure water (H2O), salt (NaCl), and methane (CH4). 9 Substance and Mixture Mixtures are two or more substances that are mixed together without chemical reaction and can be separated by physical means into their original components. The mixture can be : Homogeneous mixtures are mixtures whose components cannot be distinguished by naked eyes. – Examples: blood plasma, rainwater, tap water, air, juice, tea... Heterogeneous mixtures are mixtures whose components can be distinguished by naked eyes. – Examples: sand in water, human skin.... 10 Separation Techniques Some methods of separation Separation techniques are used to separate mixtures into its constituent elements and/or compounds. Loading… Old methods for separation. Modern methods for separation. 11 Physical Processes for Matter Matter can often change from one physical state to another in a process called a physical change. For example, liquid water can be heated to form a gas called steam or steam can be cooled to form liquid water 12 13 Physical Processes for Matter Melting is a process (phase transition) in which the substance changes from a solid to a liquid by heating. o The temperature at which solid melts and changes to liquid is termed melting point (m.p). Boiling or Vaporization is a process in which the substance changes from liquid to gas by heating. o The temperature at which liquid boils or the temperature at which liquid changes to gas is termed boiling point (b.p). Sublimation is a process in which the substance changes from solid to gas by heating without becoming a liquid. 14 Solutions The solution is a homogeneous mixture of two or more substances, consisting of ions or molecules. 15 16 Solutions Solutions may exist in any of the three states of matter; that is, they may be gases, liquids, or solids (according to the state of the solvent). – Gaseous solution: Air (O2, N2, others) – Liquid solution: Ethanol in water, CO2 in water, NaCl in water. – Solid solution: Gold-silver alloy, Dental-filling alloy 17 Solutions , colloidal and suspension The solute particle in true solutions are molecules having diameter less than 1 nmThe particle size in colloidal solution lies in the range 1nm to 100 nm.The size of the particles in the case of suspension is greater than 100 nm 18 Solutions , colloidal and suspension 19 Solubility and solubility test Solubility is the ability of a solid, liquid, or gaseous chemical substance (referred to as the solute) to dissolve in solvent (usually a liquid) and form a solution. The solubility of a substance fundamentally depends on the solvent used Solubility is a very important physicochemical parameter of a compound ,Solubility test is a type of test used to determine the ability of compounds to dissolve in a solvent – usually liquid - at equilibrium. 20 Solubility terms 21 Solubility 22 concentration In chemistry, concentration refers to the amount of a substance in a defined space. either solvent. Concentration is usually expressed in terms of mass per unit volume..When a solution contains more solute than it can theoretically hold at a given temperature, the solution is said to be (unsaturated) Concentration = mass of solute in games volume in dm3 (L) 23 Solubility terms 24 Assignment What is the role and importance of chemical solutions in health? The assignment is being prepared and presented by 4 students, and it is displayed to everyone in the class in the form of a presentation(Microsoft PowerPoint). 25 Class Work 26 Class Work Which of the following is a mixture A-sodium chloride NaCl B-NaCl and water C-Water If 8 g of aspirin is dissolved in 2.5 dm3 of water. Calculate the concentration of the aspirin solution formed. A-32 B.320 C.3.2 27