Name ____________________________________ Date ___________________ Pr. ___________ Review for Ch. 8 Test 8.1 Describing Chemical Reactions - know how to write word equations (i.e. you have be able to name compounds, including acids, ionic, and covalent compounds from Ch. 7) - know how to write a formula equation - What 2 things do coefficients represent in an equation? Relative number of moles of a substance ; relative number of molecules needed for a reaction to occur - know common symbols used in a reaction - know 4 evidences of a chemical reaction: 1. energy in the form of heat of light 2. production of a gas 3. change in color 4. formation of a precipitate - know the Law of conservation of matter: matter can neither be created nor destroyed in a chemical reaction (which means, mass of reactants must equal the mass of products) - know what a chemical equation represents: relative amounts of reactants and products - know how to balance chemical equations (combustion reactions are particularly tricky, practice!) 1. Complete the equation and write a word equation for the following reaction: ZnO + FeSO4 ZnO + FeSO4 ZnSO4 + FeO Zinc oxide reacts with iron (II) sulfate to yield zinc sulfate and iron (II) oxide 2. Write a formula equation for the reaction of a solution of AgCl with potassium metal: AgCl (aq) + K (s) KCl (aq) + Ag (s) 3. What elements are always diatomic gases at room temperature? All of the halogens (Group 17) , H2, N2, O2 4. Can you balance these reactions: a) 2 C2H6 (g) + 7 O2 (g) 4 CO2 (g) b) 2 Cu2S (s) + 3 O2 (g) 2 Cu2O (s) c) 2 Al (s) + 3 Pb(NO3)2 (aq) + 6 H2O (g) + 2 SO2 (g) 2 Al(NO3)3 (aq) + 3 Pb (s) Name ____________________________________ Date ___________________ Pr. ___________ 8.2/8.3 Types of Reactions & the Activity Series - know how to classify reaction types as synthesis, decomposition, single displacement, double displacement, or combustion. - be able to use solubility rules to identify the phases of ionic compounds: (aq) or (s) *aqueous means: substance is dissolved in water - What is a precipitate (ppt)? Insoluble solid that is produced in a reaction - be able to identify the phase of matter for elements and compounds (covalent and pure elements) - know your polyatomic ions!!!! And charges of main group elements - be able to predict the products of a reaction - practice, practice, practice!! 5. What is an activity series? When/why do you need to use an activity series? List of elements in the order of their chemical reactivity (highest at the top). Elements that have more reactivity are able to replace any elements that are below it on the activity series. Needed for Single Displacement reactions - to see if a pure element is able to replace an element of a compound. 6. In a double displacement reaction, one of the following three things must be formed or it is a no reaction – 1) precipitate 2) water 3) gas 7. Reminder: transition metals usually require the use of a roman numeral in the name [Ex: copper(I) vs. copper(II) ]; but these are exceptions and must be memorized Zn: +2 Cd: +2 Ag: +1 8. What are hydrocarbons? When a hydrocarbon is combusted what must the products be? Compounds that contain carbon and hydrogen; when combusted (i.e. reacted with oxygen) the products are always carbon dioxide and water 9. What is electrolysis? Decomposition of water into hydrogen and oxygen using electricity 10. When does a neutralization reaction occur? What two products are always formed? Subcategory of double displacement reactions – when you react an acid and base together. Products are always water and an ionic compound (known as a salt). *On the test, you will be given solubility charts, an activity series, and a periodic table.* **See my webpage for answer keys to our practice worksheets ***Don’t forget you can review WebAssign – log on and request a key to help you review