Metals in the building industry Name three parts of a building where a metal might be found In reinforced concrete On the roof On the outside of the walls For air conditioning ducts
True Metal properties False All metals have high boiling points Malleable means that metals can be drawn out into wires When a metal combines with oxygen it forms a base
Metals can only be found on the right hand side of the periodic table There are three magnetic metals, Fe, Co and Ni. Most metals conduct heat an electricity Why are metals used? What properties of a metal make it useful in building? Most are solids at
normal temperatures They are shiny and reflective Some are unreactive They are malleable Some are strong They are ductile Why are some metals not used? What properties of metals are not useful
for building materials Electrical conductivity Thermal conductivity Magnetism (mostly) Cost Environmental impact True Non-metals
False Most non metals have low boiling points They conduct heat well Non metals have acidic oxides Non metals are found in the middle of the periodic table Non metals are neither magnetic nor malleable There are more non-metallic elements than metallic ones
Non-metals What properties of non-metals make them useful in building materials Thermal insulators Do not conduct electricity Since around half of the nonmetals are gases at room
temperature, or have low melting points, very few non-metallic elements are used for building materials. There is one exception what is it? Carbon! Carbon has several different forms, or allotropes.
More on Carbon Carbon is an unusual nonmetal. It forms giant structures It has a very high melting point (> 3000 o C) Graphite conducts electricity
Activity Read page 57 and answer questions on your notebook. Concepts Density: Mass of a substance per unit of volume. E.g. We can have 7.8g of Iron in 1cm3. Pa (Pascal): Unit of pressure. Force exerted per each m2 . Chemical reactions
1. Which of the following is an example of a physical change? A. dissolving salt into water B. hard-boiling an egg C. burning wood into charcoal D. rusting iron 2. Which of the following is an example of a chemical change? A. ice melting B. pounding gold into a coin C. paint fading D. a puddle of water evaporating 3. A chemical change occurs whenever .
A. substances are mixed B. objects change shape C. hot objects melt D. new substances form 4. A chemical change can only be reversed by change. A. a chemical B. a physical C. both a physical and a chemical D. a phase
What is a chemical reaction? A chemical reaction is the change of a substance into a new one that has a different chemical identity. A chemical reaction is usually accompanied by easily observed physical effects, such as the emission of heat and light, the evolution of gas, or a color change. Absolute confirmation of a chemical change can only be validated by chemical analysis of the products. In all chemical reactions mass is conserved. Atoms of elements are rearranged.
Gasoline burns in an engine Gasoline contains isooctane (C8H18) Oxygen gas (O2) During a chemical reaction, the bonds between some atoms break. The atoms rearrange and new bonds form. In other words, the atoms recombine to form new substances. Atoms are never destroyed in a chemical reaction. The energy used to break and rearrange bonds is called chemical energy. Bond: an attraction between atoms that allows the formation of chemical
substances that contain two or more atoms. REACTANTS AND PRODUCTS A reactant is a substance that participates in a chemical reaction. A product is a substance that is formed during a chemical reaction. What Are Endothermic and Exothermic Reactions? During a chemical reaction, energy is needed to break bonds in the reactants. In an endothermic reaction, more energy is needed to break the bonds in the reactants than is released when new bonds form in the products. In other words, endothermic reactions
absorb more energy than they release. Eg. Ice starts to melt which absorbs energy and are endothermic reactions. In an exothermic reaction, more energy is released when new bonds form than is needed to break bonds. In other words, exothermic reactions release more energy than they absorb. Eg. Nuclear bombs give off energy and are exothermic reactions. Answer these questions on your notebook 1. What are three clues that may tell you a chemical reaction is happening? 2. Caramel forms when table sugar, C12H22O11 , reacts with oxygen. What
elements make up caramel? 3. Identify whether or not each of the following is a chemical reaction. Explain your answers. a. melting ice b. burning a candle c. rusting iron 4. Is a firecracker exploding an example of an endothermic reaction or an exothermic reaction? Explain your answer. Class Activity and Homework Types of chemical reactions SYNTHESIS REACTIONS
DECOMPOSITION REACTIONS SINGLE-DISPLACEMENT REACTIONS DOUBLE-DISPLACEMENT REACTIONS COMBUSTION REACTIONS Synthesis Reaction (Combination Reaction) In a synthesis reaction, two or more substances join to form a new compound. DECOMPOSITION REACTIONS
In a decomposition reaction, substances break apart. E.g. Water can break apart in a decomposition called electrolysis. SINGLE-DISPLACEMENT REACTION In a single-displacement reaction, one atom or ion replaces another atom or ion in a compound. A more reactive element will take the place of a less reactive one in a single-displacement reaction. DOUBLE-DISPLACEMENT REACTIONS
In a double-displacement reaction, two atoms or ions appear to replace one another in compounds. COMBUSTION REACTIONs In a combustion reaction, organic compounds react with oxygen. All combustion reactions produce carbon dioxide and water. E.g. An organic compound is the Glucose (C6H12O6). It reacts with Oxygen (O2) to form Carbon Dioxide and Water. INCOMPLETE COMBUSTION When there is not enough oxygen during a combustion reaction, only
some of the fuel is converted to CO2. The combustion reaction is incomplete and produces Carbon Monoxide (CO) which is a poisonous gas. Worksheet - AIC Homework - TAI Activity Write the name of the type of reaction next to each equation. SYNTHESIS S8 + O2 8SO2 ________________________________________ SYNTHESIS
6Li + N2 2Li3N ________________________________________ DOUBLE DISPLACEMENT AgNO3 + KBr AgBr + KNO ________________________________________ DECOMPOSITION CaCO3 CaO + CO2 ________________________________________ SINGLE DISPLACEMENT Mg + Pb(NO3)2 Pb + Mg(NO3)2 ________________________________________ COMBUSTION 2C8H18 + 25O2 16CO2 + 18H2O ________________________________________ SYNTHESIS Ca + S CaS ________________________________________
DOUBLE DISPLACEMENT Ca3(PO4)2 + 3H2SO4 3CaSO4 + 2H3PO4 ___________________________________ SINGLE DISPLACEMENT SiO2 + 2C Si + 2CO ________________________________________ DECOMPOSITION 2CaCO3 2Ca + 2C + 3O2 ________________________________________ Acids, Bases, and ph What is an Ion? An atom or a group of
atoms that has acquired electric charge by gaining or losing one or more electrons. What is an acid? An acid is a substance that contain hydrogen ions (H+). If dissolved in water, acids produce hydronium ions (H3O+). Properties
Sour taste Corrosive (able to destroy or eat away certain materials) Poisonous React with some metals Acids conduct electricity. E.g. Car battery
Turn blue litmus paper red What is a base? These are substances which can neutralize acids. Metal oxides and hydroxides (Eg. magnesium oxide and magnesium hydroxide) are bases. Soluble bases are called alkalis and produce OH(hydroxide ions) in solution. Alkalis have a high pH over 7 on the pH scale Properties
Bitter taste Feel slippery Conduct electricity Turn red litmus paper blue Corrosive
What is ph? The pH of a solution is a value that expresses how acidic or basic a solution is. Indicators An indicator is a substance that changes color if a solution is acidic or basic. Litmus paper (red or blue) pH paper Bromthymol blue
Answer these questions on your notebook. 1. What kind of ions do acids produce when you dissolve them in water? What kind of ions do bases produce? 2. A solution conducts electric current. Can you use this property to determine if the solution is an acid or a base? Explain 3. What happens to red litmus paper when it touches a household cleaner that has ammonia in it and why? 4. Suppose you are doing an experiment and your fingers feel slippery. What did you probably get on them? What should you do if this happens to you? 5. Arrange the following substances in order of increasing acidity: vinegar
(pH = 2.8), stomach acid (pH = 2.0), and a soft drink (pH = 3.4) Equations Word Equations A word equation describes a chemical reaction using words. In the naming of compounds between metals and non-metals: metallic elements are named first non-metallic elements are named second and the suffix is changed to to an "ide" Non metal
Hydrogen Oxygen Sulfur or sulphur Nitrogen Phosphorus Suffix change Hydride Oxide Sulfide or sulphide Nitride
Phosphide Non metal Fluorine Chlorine Bromine Iodine Astatine Suffix change Fluoride
Chloride Bromide Iodide Astatide Symbol Equations A symbol equation describes a chemical reaction using the element symbol. What does the symbol equation of the compound tell us? In copper sulphate, CuSO4 there are four atoms of
oxygen and one atom of sulphur for each one of copper. CuSO4 Cu - 1 How many elements and SO-
1 4 atoms in KNO3 K2CO3 Na3PO4
Numbers in a Symbol Equation Word to symbol substances (Match) A A. Copper oxide 1. ______CuO B. Zinc oxide F 2. ______CuCl
2 C. Sodium hydroxide B 3. ______ZnO D. Magnesium chloride E 4. ______ZnSO
4 E. Zinc sulphate G 5. ______Cu(NO 3)2 F. D
6. ______MgCl 2 Copper chloride G. Copper nitrate C 7. ______NaOH A.
Word to symbol substances(Match) E 1. ______Ca(NO ) Zinc chloride 3 2 B. Calcium sulphate
2. ______ZnCl A 2 C. Magnesium sulphate F 3. ______NaNO 3 D. Calcium chloride
B 4. ______CaSO 4 E. Calcium nitrate C 5. ______MgSO 4
F. Sodium nitrate G 6. ______FeSO 4 G. Iron sulphate 7. ______CaCl D 2
Oxides Metal oxides (basic oxides) They are compounds formed by a metal and oxygen. Metallic oxides are basic in nature and often exist as solids at room temperature. If they dissolve in water they form alkaline solutions. METAL + OXYGEN METAL OXIDE E.g. Zinc + Oxygen Zinc Oxide
NON-METAL OXIDES (acidic oxides) Non-metal oxides such as sulphur dioxide and nitrogen oxide are responsible for acid rain. They dissolve in the water in the clouds to form acidic solutions. Acid rain damages rocks and buildings, and harms wildlife. NON-METAL+OXYGEN NON-METAL OXIDE E.g. Carbon + Oxygen Carbon Dioxide In spanish, non-metal oxides are also called anhidridos
Metal Oxides + water (Alkali) Metal oxide + H2O Metal Hydroxide + H2O E.g. Sodium oxide + water Sodium hydroxide + Water Calcium oxide + water Calcium hydroxide + water Non-metal oxides + water (Acids) NON-METAL OXIDE + H2O NON-METAL ACID E.g. Carbon dioxide + water Carbonic acid Chlorine dioxide + water Chlorine acid
Salts Salts Alkali (hydroxide) + acid Base (oxide) + acid
Metal + acid salt + water salt + water salt + hydrogen sodium hydrochlori + c
acid hydroxide calcium oxide + sulphuric acid
magnesiu hydrochlori + c acid m sodium chloride
+ water calcium sulphate + water
magnesiu hydroge m + n chloride
