General Chemistry 1st Sem Reviewer PDF

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This document is a general chemistry reviewer, covering the particulate nature of matter, states of matter, and a bit of early scientific approaches to the study of matter. It is likely for high school or undergraduate chemistry students.

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GENERAL CHEMISTRY (1ST SEM - MONTHLY ASSESSMENT REVIEWER) PARTICULATE NATURE OF MATTER The Greek Concept of Atom All kinds of matter are particulate in Leucippus and Democritus nature. These particles may be in the thought that all...

GENERAL CHEMISTRY (1ST SEM - MONTHLY ASSESSMENT REVIEWER) PARTICULATE NATURE OF MATTER The Greek Concept of Atom All kinds of matter are particulate in Leucippus and Democritus nature. These particles may be in the thought that all materials are made form of molecules, atoms, or ions. up of tiny bits of matter which cannot Atoms are the building blocks of be divided further. matter. Greeks referred to this as atom (Greek word atomos, meaning Matter indivisible). Matter is anything that has mass and volume. Ancient Greek philosophers were the first to speculate the nature of matter. They only speculated on the nature of materials around them as they were not able to conduct experiments that will validate their assumptions Ancient Views on Matter Materials are made up of one primal matter. Democritus’s view of matter Particulate Nature of Matter Discontinuity of Matter: Matter is made up of particles instead of a Empedoclean Elements primal material. Aristotle suggested that all space Four main ideas is filled up with matter, thus, implying 1. Matter is composed of discrete that there are no empty spaces. particles. He described each element as a 2. There is an empty space between balance between two qualities. particles of matter. 3. The particles of matter are in constant motion. 4. There are forces that act between the particles. Three States of Matter Continuity of Matter Discrete Particles of Matter Since matter is not void, this means that it is divisible and can be cut into pieces over and over again. This started the principle of continuity of matter, wherein matter can be broken down into pieces and A block of wood (left) can be easily as you do so, you will not be able to observed as hard, and based on its obtain its smallest parts. internal composition, it is made up of compact particles (right) GENERAL CHEMISTRY (1ST SEM - MONTHLY ASSESSMENT REVIEWER) Empty Space between Particles Particulate Nature of the Three The particles that make up matter States of Matter have spaces in between them. These spaces may be little or huge, depending on the kind of matter. Motion of Particles The spaces between particles dictate the kind of movement that particles Solids are like military units. The in matter can do. particles are rigid and close to one another. Liquids are like people in a reunion party. There are small, random motions but people are close to one another. Particles that are close to one another (left) move in vibratory motion while particles that are far apart (right) move fast and in random directions. Ancient Greek philosophers were As the temperature increases, the first to speculate the nature of particles gain kinetic energy which matter by providing different results in their fast movement. assumptions on what it is made of. tulad ng baybay, bantas, at mismong nilalaman ng akademikong sulatin. The idea of Democritus paved the way in establishing that matter is Phases Changes of Matter made up of particles instead of a primal material. There are four main ideas in the particulate nature of matter: 1. Matter is composed of discrete particles. 2. There is an empty space between particles of matter. 3. The particles of matter are in constant motion. 4. There are forces that act between the particles. The arrangement of particles, its motion, and intermolecular forces dictate the kind of state in which matter exists. Forces between Particles Intermolecular forces or forces that exist between particles may be attractive or repulsive. The water particles (inside) attract one another. The glass particles and the water particles (outside) repel one another. GENERAL CHEMISTRY (1ST SEM - MONTHLY ASSESSMENT REVIEWER) PURE SUBSTANCES AND MIXTURES 118 elements known to exist Classifications of Matter arranged in the periodic table of Matter may be classified according elements to their properties. ○ 94 of these are naturally occurring physical properties - observable ○ 24 of these are synthetic even without changing the composition of DMITRI MENDELEEV matter A Russian chemist and inventor best ○ color known for creating the Periodic Table ○ size of Elements. Born in 1834, Mendeleev ○ shape arranged the 63 known elements into chemical properties - observed a table based on atomic mass, once a material undergoes am leaving gaps for elements yet to be chemical reaction discovered. His work allowed for the ○ flammability prediction of the properties of these ○ reactivity missing elements, which were later ○ biodegradability discovered and confirmed his predictions. His periodic law and Matter may be classified according table significantly advanced the field to their composition. of chemistry. pure substances ○ matter have a fixed or definite Periodic Table of Elements composition a useful tool that can help in mixtures identifying elements that exhibit ○ combinations of two or more similar properties substances classifies elements into 3 categories: Pure Substances ○ metals - leftmost of the periodic a kind of matter with a definite or table fixed composition ○ nonmetals - rightmost of the made up of a specific number of periodic table atoms or groups of atoms that are ○ metalloids - staircase-like line combined through a chemical between metals and nonmetals reaction has definite physical and chemical Metals properties general properties: classified into elements and ○ solid at room temperature compounds ○ lustrous ○ malleable ○ ductile ○ heat/electricity conductors Example: silver, tungsten, platinum, gold Mercury is the only metal that is liquid at room temperature. It is a shiny, silvery liquid metal that forms Elements beads due to its high surface tension. the simplest form of matter Mercury is also known as quicksilver made up of only one kind of atom due to its appearance and mobility. elements of different kinds also differ in the atoms that make them Nonmetals up general properties: cannot be decomposed into ○ opposite of metals simpler forms by physical ○ gaseous or dull solids or chemical means ○ poor conductors of heat and react with one another to form a electricity new substances Example: sulfur, oxygen gas GENERAL CHEMISTRY (1ST SEM - MONTHLY ASSESSMENT REVIEWER) Bromine is the only nonmetal that do not have definite proportions exists in liquid form at room and definite properties temperature. properties depend on the substances that are present in it Metalloids/Semimetals may be further classified as exhibit properties of both homogeneous or heterogeneous metals and nonmetal conducts heat and electricity Homogeneous Mixtures but not as good as how metals consists of substances that are act as conductors evenly distributed all throughout semiconductors the components cannot be distinguished from each other by the Silicon and germanium are naked eye metalloids that are widely used also known as solution in the manufacture of computer chips. Solution composed of two components: Compounds ○ solute - the substance that is composed of two or more different dissolved by another substance; elements that are combined in a fixed exists in smaller amounts ratio by a chemical reaction ○ solvent - the dissolving medium Many compounds are found in the in which the solute dissolves; environment. most abundant Some compounds are formed In a salt solution, the solute is the salt when an element reacts with another while the solvent is water. element. soluble - when substances dissolve Some compounds are products of in a given solvent chemical reactions between two or miscible - when liquids are soluble more compounds. in each other at all proportions Chemical bonds cannot be broken In a salt solution, salt is soluble in easily water. Unlike elements, compounds can may be solid, liquid or gas be broken down into simpler forms by chemical means Heterogeneous Mixtures It classified according to the consists of substances that are specific elements present not evenly distributed all throughout the components can be ○ organic compounds - contains distinguished from each other by the carbon naked eye and hydrogen can be further classified as ex. carbohydrates, proteins, lipids, colloids or suspensions etc. Colloids ○ inorganic compounds - do not a heterogeneous mixture with contain particles that are bigger than those carbon-hydrogen bonds in a solution but smaller than those ex. CO2, H2O, table salt (NaCl) in a suspension particles do not settle at the Mixtures bottom consist of two or more pure even after being left to stand for a substances that are combined long time physically exhibit Tyndall effect no chemical reaction between Milk is an example of a colloid. the components components retain their characteristic properties when mixed together each component has the same chemical makeup it had before the mixture is formed GENERAL CHEMISTRY (1ST SEM - MONTHLY ASSESSMENT REVIEWER) Tyndall Effect Matter may be classified according the phenomenon wherein light is to their composition: pure scattered. substances and mixtures. A pure substance is a kind of matter with a definite or fixed composition. A mixture is a kind of matter that consists of two or more substances that are combined physically. Pure substances are classified as Suspensions elements or compounds. a heterogeneous mixture with ○ An element is the simplest form of suspended particles that are large matter made up of one type of atom. enough to be seen by the naked eye ○ A compound is made up of particles settle at the bottom of different types of atoms that are the container due to gravity combined chemically. To easily distinguish the types of mixtures, always refer to the uniformity of its appearance. Homogeneous mixtures have a uniform appearance while heterogeneous mixtures are not uniform in terms of their appearance.

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