General Chemistry PDF

EEN NEERR A ALL G G EM CHHEMIISSTR TRYY C atoms atoms The electrons of an atom are found orbiting the nucleus of the atom The smallest particle. It is composed of...

EEN NEERR A ALL G G EM CHHEMIISSTR TRYY C atoms atoms The electrons of an atom are found orbiting the nucleus of the atom The smallest particle. It is composed of Electrons have a negative charge. protons, which have a positive charge, and neutrons, which have no charge. molecules molecules It is a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction. Phases Phases of of matter matter Solids have definite: ions ions Mass Is an atom or molecule with a net electric Volume charge due to the loss or gain of one or more Shape electrons. Liquid a type of matter with specific properties what what is is matter? matter? that make it less rigid than a solid but more rigid than a gas Matter is anything that has mass and Gases have NO definite volume. Mass The definition of matter is often taken to Volume mean anything composed of atoms and Shape molecules. Plasma is the form of matter that exists when the Thus, matter is anything made of atoms are in an excited state. protons, neutrons, and electrons. Stars (the sun is a star) exist in the plasma The atom is the “building block of state because of nuclear fusion. matter”. Some examples of plasma found on Earth All substances are composed of invisible are: lightning, auroras, and neon. particles called atoms. Atoms are the building blocks of matter and are in constant motion. The combination of atoms leads to millions of materials with different properties. what what is is atom? atom? Atoms are composed of three types of particles: protons, neutrons, and electrons. Atoms are made up of a positively charged center, the nucleus, containing: Protons with a positive charge Neutrons with no charge (neutral) Physical Physical state state of of matter matter properties properties The physical form in which a substance A property of matter that can be observed or exists at room temperature, such as: measured without changing the identity of the Solid – matter has a definite shape matter. and volume Physical properties identify matter. Liquid – matter takes the shape of its EXAMPLE includes but are not limited into: container and has a definite volume Density Gas – matter changes in both shape Malleability and volume Ductility thermal thermal Solubility State conductivity conductivity The ability to transfer thermal energy Thermal Conductivity from one area to another. DENSITY DENSITY EXAMPLE: Plastic foam is a poor conductor, so a hot drink won’t burn your hand. The inside Amount of mass in a given volume of the toaster (hot coils) A substance is always the same at M a given pressure and temperature D V CHEMICAL CHEMICAL regardless of the size of the sample properties properties of the substance. The density of one substance is usually A property of matter that describes a different from that of another substance. substance based on its ability to change Density equals mass divided by volume. into a new substance with different properties. malleability malleability Can be observed with your senses. The ability to be pounded into thin sheets. Are Not as easy to observe as physical EXAMPLE: Aluminum can be rolled or pounded properties into sheets to make foil. EXAMPLE: Combustibility - Only when fireworks DUCTILITY DUCTILITY explode The ability to be drawn or pulled into a wire Flammability - Only when wood burns EXAMPLE: Copper in wiring – soldering wires or Reactivity - Only when iron Oxidizes joints (rust) Acids SOLUBILITY SOLUBILITY Bases The ability to dissolve in another substance. Oxidation Three ways to increase solubility Heat or make warmer Grind or smash Stir or mix EXAMPLE: sugar or salt dissolve in water 55 signs signs of of a a extensive chemical extensive property property chemical An extensive property is a property that depends change change on the amount of matter in a sample. Such as The only sure way to know there has MASS, LENGTH, SIZE and VOLUME been a chemical change is the observance The mass of an object is a measure of the amount of a new substance formed of matter that an object contains. A small sample Sometimes that is hard to do, so look for of a certain type of matter will have a small mass, the signs……. while a larger sample will have a greater mass 1. 1. Odor Odor intensive intensive property property production production An intensive property depend on the type of This is an odor far different from what it matter. These include DENSITY, COLOR, should smell like PHYSICAL STATE, MELTING, BOILING Ex: Rotting eggs, food in fridge, POINT & FREEZING POINTS, and decomposing flesh THERMAL CONDUCTIVITY. Intensive properties may also used to identify a 2. 2. Change Change in in substance. temperature temperature The electrical conductivity of a substance is a Exothermic - When energy is released do property that depends only on the type of during the chemical change ex: wood substance. Silver, gold, and copper are excellent burning conductors of electricity, while glass and plastic Endothermic - Energy is absorbed causing are poor conductors. A larger or smaller piece of a decrease in temperature of the reactant glass will not change this property material ex: cold pack in first aid kit Consumer Consumer 3. 3. Change Change in in Products Products color color A Consumer Product is any item often bought for Ex: fruit changing color when it ripens, consumption. One commonly encountered class leaves changing color in the Autumn, of consumer products are convenience products - dying your hair those that appeal to a large segment of the market or those that are routinely bought. 4. 4. formation formation Consumer products are something that we of of bubbles bubbles cannot live without. Every activity we do such as This can indicate the presence of a gas. taking a bath, cooking our favorite dishes, driving Bubbles produced when boiling water is our cars or monitoring and maintaining our good not a chemical change. health condition, there will always be a consumer product that is involved. Those consumer 4. 4. formation formation of of products were made possible because of the a precipitate a precipitate interactions of Science, Technology and Society. When two liquids are combined and a solid is produced Law Law of of 1. The atomic number identifies an element. Conservation Conservation The atoms of isotopes of an element have the of of Mass Mass same number of protons and electrons. In a chemical reaction, no change in mass 2. The atoms of isotopes of an element differ in takesplace. The total mass of the products is the number of neutrons. equal to the total mass of the reactant Ions Ions DALTON’S DALTON’S Ions can be made up of only one atom ATOMIC ATOMIC THEORY THEORY (monoatomic) or more than one type of atom (polyatomic) 1. Matter is made up of extremely small Monoatomic ions are named based on the indivisible particles called atoms. element. 2. Atoms of the same elements are identical, a. For cations, the name of the element is and are different from those of other unchanged. If an element can form two ions elements. of different charges, the name, which is 3. Compounds are formed when atoms of usually derived from its Latin name, is different elements combine in certain modified by the suffix –ic for the ion with whole - number ratios. the higher charge, and –ous for that with the 4. Atoms rearrange only during a chemical lower charge. reaction to form new compounds. b. For anions, the name of the element is Relative modified by the suffix –ide. Particle Location Charge Mass EXAMPLE: EXAMPLE: a. Zn2+ a. Br- Proton Nucleus +1 1 b. Mg2+ b. S2- Outside c. K+ c. O2- Electron nucleus -1 0.0006 d. Fe2+ d. I- Neutron Nucleus 0 1 e. Fe3+ e. F- Several anions are polyatomic and are named Atomic number = number of protons = based on the atomic constituents and the suffix – number of electrons in a neutral atom ide. Mass number = number of protons + EXAMPLE: number of neutron a. OH- = hydroxide ion isotopes isotopes b. CN- = cyanide ion there are atoms of an element having the same A number of polyatomic anions containing atomic number but different mass number. oxygen atoms are named based on the root word The existence of isotopes was shown by mass of the central (or non-oxygen) atom and the suffix spectroscopy experiments, wherein elements –ate for the one with more oxygen atoms and – were found to be composed of several types of ite for the one with less oxygen atom. atoms, each with different masses. EXAMPLE: a. NO3- – nitrate ion d. SO42- – sulfate ion b. NO2- – nitrite ion e. PO43- – phosphate ion c. SO3 2- – sulfite ion  Some anions have common names ending with EXAMPLE: the suffix –ate. 1. magnesium fluoride EXAMPLE: 2. zinc sulfate a. C2H3O2- – acetate ion 3. aluminum hydroxide b. C2O4 2- – oxalate ion EXAMPLE: 1. KBr CHEMICAL CHEMICAL 2. Pb(NO3)2 FORMULA FORMULA 3. AgClO3 The formula consists of the symbols of the atoms Molecular compounds – made up of two making up the molecule. If there is more than non-metals. They are named by giving one atom present, a numerical subscript is used. the name of the first nonmetal and then EXAMPLE: that of the second nonmetal modified by a. O2 – oxygen gas the ending -ide. Molecular compounds b. H2O – water are usually gase c. NaOH – sodium hydroxide (liquid Sosa) GREEK PREFIXES d. HCl – hydrochloric acid (muriatic acid) 1 - mono 6 - hexa 2 - di 7 - hepta MOLECULAR MOLECULAR 3- tri 8 - octa FORMULA FORMULA 4 - tetra 9 - nona gives the composition of the molecule, in terms of 5 - penta 10 - deca the actual number of atoms present. EXAMPLE: TERNARY TERNARY C6H12O6 COMPOUND COMPOUND made up of three elements. The naming EMPIRICAL EMPIRICAL of ternary compounds follows the same FORMULA FORMULA rule as that of the binary ionic compound: gives the composition of the molecule, in terms of the name of the cation is given first, the smallest ratio of the number of atoms present. followed by the name of the anion EXAMPLE: EXAMPLE: CH2O a. NaNO3 b. BaCrO4 BINARY BINARY c. K2SO4 COMPOUND COMPOUND made up of two elements. Discuss the rules for naming in two groups of binary compounds. Ionic compounds – made up of a cation and an anion. They are named by giving the name of the cation first, followed by the name of the anion. EXAMPLE: a. NaI (sodium iodide) c. FeS (ferrous sulfide) b. MgCl2 (Magnesium d. K2O (potassium 0xide) Chloride) naming naming of of acids acids Acids – yield hydrogen ions in aqueous solutions Binary Binary acids acids composed of hydrogen and another element, usually a nonmetal. The first part of the name starts with the prefix hydro- followed by the name of the element, modified by the ending –ic. The second part consists of the word ‘acid’. Name = hydro-(root name of element) -ic + acid EXAMPLE: i. HCl (hydrochloric acid) ii. H2S (hydrosulfuric acid) iii. HI (hydroiodic acid) ternary ternary acids acids made up of hydrogen and an anion, usually containing oxygen. The first part of the name consists of the root word of the name of the element, modified by the ending –ic. The second part consists of the word ‘acid’. If there is another acid with the same atoms, the suffix –ous is used to denote the one with less number of atoms. Name = (root name of element) -ic (or –ous) + acid EXAMPLE: i. HNO3 (nitrogenic acid) ii. HNO2 (nitrogenous acid) iii. H2SO4 (sulfuric acid) iv. H2SO3 (sulfurous acid) v. H3PO4 (phosphoric acid)