Quiz: 1. Name the following compounds Ag2SO4 KOH FeCl2 Na2CO3 FeO 2. Give the formula of the following compounds. lithium sulfate aluminium sulfide lead chloride 3. Ionic compounds are formed when a _________ charged ion called cation binds to a negatively charged ion called _________ through _______________ attraction. 4. Explain the similarities and differences between a magnesium atom and a magnesium ion (make sure you include No of subatomic particles, charge, electron arrangement of each and how atom turns into ion) 5. Write the formula for aluminium sulfide, and explain why the formula has 2 aluminium ions for every 3 sulfide ions.

Quiz: 1. Name the following compounds Ag2SO4 KOH FeCl2 Na2CO3 FeO Silver sulfate, potassium hydroxide, iron (II) chloride, sodium carbonate and Iron(II) oxide. 2. Give the formula of the following compounds. lithium sulfate aluminium sulfide lead chloride Li2SO4 Al2S3 PbCl2 3. Ionic compounds are formed when a _positively_ charged ion called cation binds to a negatively charged ion called _anion_ through _electrostatic_ attraction. 4. List the similarities and differences between a magnesium atom and a magnesium ion (make sure you include No of subatomic particles, charge, electron arrangement of each and how atom turns into ion) 5. Write the formula for aluminium sulfide, and explain why the formula has 2 aluminium ions for every 3 sulfide ions.

Chemical reactions: A chemical reaction happens when substances (called reactants) react to form new substances (called products) which have different physical or chemical properties.

Chemical equations: A chemical equation is a way of showing what substances react and what new products are formed. Chemical reactions can be written in both words or symbols. (Both you will have to know both) For example: Combustion of hydrogen Word equation: hydrogen + oxygen → water  Symbol equation: 2H2 + O2 → 2H2O Note that the number in front of the chemicals represent the ratio of each type of substances involved in the reaction and these are called coefficients.

How to do chemical reactions Write down the names of the reactants and products. Write down the correct formula for the reactants and products. Balance the equation by putting numbers in front of each reactant and product so that the number of each type of elements are balanced on both sides. E.g. H2 + O2 → H2O 2H and 2O on the left but only 2H and 1O on the right Therefore H2 + O2 → 2H2O We put 2 on the right to have 2Oxygens But now there’s 4H on the right SO we put another 2 in front of the H on the left 2H2 + O2 → 2H2O

Your task In groups of two or three get a Bunsen, some matches and a few pieces of magnesium ribbon, burn the magnesium ribbon using a tong (don’t stare at it), Collect the ashes and put it in small amounts of water and test for its acidity using universal indicator. Each group get a few zinc granules and some hydrochloric acid (HCl) in a test tube, react the zinc granules with the acid, hold your hand over the top to stop gas from escaping, move your hand Demonstration of sulfur burning in air. Write a word and a balanced symbol equation for above three reactions.

Quiz: 1. The substances that react with each other in a chemical reaction are called _____________ and the substances formed are called _____________. 2. What does the number in front of the chemicals indicate? 2H2 + O2 → 2H2O 3. Yesterday we burned some magnesium in air, which gave off a bright light and formed a white powder. The chemistry involved is magnesium reacting with oxygen giving magnesium oxide. Write a word and balanced symbol equation for the reaction.

They are everywhere.. In your food In your house EVEN IN YOU!!!!! Acids & Bases They are everywhere.. In your food In your house EVEN IN YOU!!!!!

What is an acid? An acid is a solution that has an excess of H+ ions. It comes from the Latin word acidus that means "sharp" or "sour". The more H + ions, the more acidic the solution.

Properties of an Acid Tastes Sour Conduct Electricity Corrosive, which means they break down certain substances. Many acids can corrode fabric, skin,and paper Some acids react strongly with metals Turns blue litmus paper red Picture from BBC Revision Bites http://www.bbc.co.uk/schools/ks3bitesize/science/chemistry/acids_bases_1.shtml

Uses of Acids Acetic Acid = Vinegar Citric Acid = lemons, limes, & oranges. It is in many sour candies such as lemonhead & sour patch. Ascorbic acid = Vitamin C which your body needs to function. Sulfuric acid is used in the production of fertilizers, steel, paints, and plastics. Car batteries

What is a base? A base is a solution that has an excess of OH- ions. Another word for base is alkali. Bases are substances that can accept hydrogen ions

Properties of a Base Feel Slippery Taste Bitter Corrosive Can conduct electricity. (Think alkaline batteries.) Do not react with metals. Turns red litmus paper blue.

Uses of Bases Bases give soaps, ammonia, and many other cleaning products some of their useful properties. The OH- ions interact strongly with certain substances, such as dirt and grease. Chalk and oven cleaner are examples of familiar products that contain bases. Your blood is a basic solution.

pH Scale pH is a measure of how acidic or basic a solution is. The pH scale ranges from 0 to 14. Acidic solutions have pH values below 7 A solution with a pH of 0 is very acidic. A solution with a pH of 7 is neutral. Pure water has a pH of 7. Basic solutions have pH values above 7.

Common acids and bases Acids include Hydrochloric acid HCl Sulfuric acid H2SO4 Nitric acid HNO3 Bases include Hydroxide OH- Metal oxides such as CaO, MgO

pH Scale A change of 1 pH unit represents a tenfold change in the acidity of the solution. For example, if one solution has a pH of 1 and a second solution has a pH of 2, the first solution is not twice as acidic as the second—it is ten times more acidic.

Acid – Base Reactions A reaction between an acid and a base is called neutralization. An acid-base mixture is not as acidic or basic as the individual starting solutions.

Acid – Base reactions Each salt listed in this table can be formed by the reaction between an acid and a base.

Get some hydrochloric acid in a test tube . Experiment: Anta-acid, do they work? We are going to test if anta-acid works as it should (to neutralize acid) Get some hydrochloric acid in a test tube Use mortar and pestle (grinder) to powder some anta-acid tablets. Put a few drops of universal indicator in the test tube with acid. Slowly add some anta-acid powder and see if there’s a color change. Also if you have time: test some common chemicals to see if they are acidic or basic. Once you finish, try work out the chemical equation for the reaction of sulfur and oxygen and reaction of HCl with anta-acid.

Chemical equations for practice Write the symbol equation for Aluminium oxide  aluminium and oxygen Iron metal + oxygen  Iron (III) oxide Magnesium metal + chlorine gas  magnesium chloride Copper(II) chloride  Copper metal + chlorine gas Sulfur dioxide + oxygen  sulfur trioxide.