Unit 6 Chemical Reactions Key

Name:___________________ Per:____ Unit 6 Outline– Chemical Reactions Essential Skills/ State Standards 6-1. Name and write formulas for common ionic and covalently bonded substances. 6-2. Describe the reactants and products of chemical reactions and physical changes. 6-3. Identify the 5 common types of chemical reactions. 6-4. Write balanced chemical equations. Vocabulary: Chemical change Chemical reaction Single replacement reaction Soluble Insoluble Reverse reaction physical change Combustion reaction Double replacement reaction Precipitate Conservation of mass Diatomic molecule Activity series Synthesis reaction Balanced Chemical Equation Subscript Coefficient Polyatomic ion Reactants Prodcucts “Swap-and-Drop” Formula Unit Aqueous Study Guide (This is only a partial review- use your labs, book assignments, and worksheets too) 1. Given the following equations, determine if a physical change or chemical change has occurred & explain how you know: a) CO2 (s) + H2O → H2CO3 (g) Chemical- different substances in reactants and products b) CO2 (s) → CO2 (g) Physical – Same substance in reactants and products, it just had a faze change. 2. Can you read a chemical equation? Identify the reactants, products & all the bolded symbols below: AgNO3 (aq) + MgBr2 (aq)  AgBr (s) + __ Mg(NO3)2 (aq) = aqueous… means dissolved in water += combined with turns into/ produces (s) = solid 3. On the image, identify: a) the bonds that break during a chemical reaction & also name. …. = hydrogen bonds that are weak, these break during physical changes When something changes from a solid to a liquid. Ex: water molecules break away from each other. b) the bonds that break during a physical reaction & also name. _____ = strong bonds that break in chemical reactions and separate atoms from each other. Ex: water is broken into H & O 4. What are 4 potential indicators of a chemical reaction? 2 liquids make a solid (precipitate) color change gas heat or light given off 5. Name Rule? (ex: 2 non-metals) Formula a. barium hydroxide metal + polyatomic ion b. sulfur tetraoxide 2 nonmetals SO4 c. diarsenic trisulfide 2 nonmetals As2S3 d. sodium carbonate metal + polyatomic ion e. ammonium sulfate both polyatomic ions f. Bromine Diatomic molecule g. Gold (I) phosphate Transition metal + polyatomic ion Au3PO4 h. Barium Carbonate metal + polyatomic ion BaCO3 6. Formula Total # of atoms Br2 Total number of ions Charge on cation 9 3 Mg Al(OH)3 7 4 Al 7. Balance the following equations & ID the type of reaction: 2 CO + O2 2 CO2 2+ 3+ Charge on anion (NO3)-1 (OH)-1 Chem. Reaction Type: synthesis Molar mass 148g/ mole (periodic table) 78 g/ mole Will the reaction occur? Why? Yes, always do Single Yes, Na is higher on activities series than H b. 2 Na + c. 2 AgNO3 + MgCl2  2 AgCl + Mg(NO3)2 double Yes, AgCl is solid d. 2P2O5  4 P + Decomp Yes, always do Combustion Yes, always do 2 H2O  2 NaOH + 5 O2 e. CH4 + 2 O2 ____ CO2 + 2 H2O 8. Na2CO3 (NH4)2SO4 Mg(NO3)2 a. Ba(OH)2 H2 a. What law in nature requires that chemical reactions be balanced? How does it work? The Law of conservation of matter/ mass. “What goes in must come out.” b. For: 2 Al(OH)3 What is the 2 called & why is it there? What is the 3 called & why is it there? 2 is a coefficient, these are written in order to balance and equation 3 is a subscript that is used to correctly write the formula. Swap and drop the charge of 3 from Al. 9. List the 7 diatomic elements & explain why they are diatomic. H2, N2, O2, I2, F2, Cl2, Br2… All these elements bond with themselves to make the octet rule instead of being a single, monoatomic atom like the noble gases and metals. 10. Write the correct formulas, state of matter, and equations, & balance: a. Aqueous iron (III) nitrate reacts with a solution of ammonium sulfate to yield aqueous ammonium nitrate and aqueous iron (III) sulfate. 2Fe(NO3)3 (aq) + 3(NH4)2SO4  6NH4 NO3 (aq) + Fe2(SO4)3 (aq) (double replacement) b. Solid mercury (I) oxide breaks down to form liquid mercury and oxygen gas. 2Hg2O (s)  4Hg (l) + O2 (g) (decomposition) 11. Complete the following chart. Reactants Predict the Products (make sure to balance equations) a. ___2_ Fe(NO3)3 + _3___ Pb  (Pb 2+ is most common) b. ___1_ C5H12 + __8__ O2  3Pb(NO3)2 + 2Fe c. __3_NaNO3 + _1__FeBr3  Fe(NO3)3 + 3 NaBr 6 H2O + 5 CO2 12. Based on the solubility chart, identify if the substances are a solid (precipitate) or aqueous: a. ZnCO3 b. K3PO4 c. Ca(OH)2 d. Al2(SO4)3 solid aq solid aq 13. Based on the activity series which element is more likely to replace the other in a compound? a. K and Na b. Al and Ni c. I and F