Chemistry Year End Review

Chemistry 1.) Name two metals and two non-metals and describe the general area that metals and non-metals are found on the periodic table. - Metals _____ Sodium (Na) _____ and ____ Iron (Fe) ____ - Non-metals ____ Oxygen (O) ____ and ____ Iodine (I) ____ Metals are found to the left of the “steps” of the periodic table and non-metals are found to the right of the “steps”. 2.) a.) What is the most reactive element on the periodic table (think most dangerous gas)? Fluorine gas. b.) Describe the general trend that occurs on the periodic table that describes where the most and least reactive elements are found. As one goes from left to right and bottom to top the elements the general trend is to become more reactive. Most reactive 3.) What indicates that a chemical is an acid or a base? Compounds that start with an H are acids and compounds that end in an OH are bases. 4.) a.) What word describes what acids, bases, and salts do when put in water? Dissociate. b.) Name two properties of acids and bases. Acids Bases Sour taste Bitter taste Conduct electricity Conduct electricity React with metals Don’t react with metals KEY c.) What is the name of the scale used to measure strength of acids and bases. pH scale. pH stands for “the power of hydrogen”. d.) Which solution has more H+ ions, and how much more, in a solution with a pH of 3 than a solution with a pH of 9? pH of three has much more H+ ions as it is the stronger acidic solution. There are 10x more H+ ions for each digit that 3 is lower than 9. So . . . pH of 3 has 106 or 1 000 000 (million) times more H+ ions in solution. e.) Write the name and formula of two acids and two bases. Acids = sulphuric acid (H2SO4), acetic acid (CH3COOH), phosphoric acid (H3PO4), and hydrochloric acid (HCl) etc. Bases = sodium hydroxide (NaOH), magnesium hydroxide (Mg(OH)2), calcium hydroxide (Ca(OH)2), aluminum hydroxide (Al(OH)3) and iron (II) hydroxide (Fe(OH)2) etc. f.) What are the products when an acid and a base are mixed? When an acid and base are mixed a salt (composed of the metal from the base and the non-metal from the acid) and water are always produced. 5.) Which subatomic particle is the largest and heaviest? Neutron. 6.) Which particle is found in the large open space in an atom? Electron. 7.) Which particle causes bonding to occur? Electron. 8.) Which particle decides what element an atom is? Proton. 9.) Describe how an ionic bond and a covalent bond are formed. Ionic – ionic bonds are formed by the metal giving up its valence electrons to the non-metal so that it has a full outer shell. Covalent – covalent bonds are formed between two non-metals sharing their valence electrons between them. 10.) Label each of the following compounds as ionic or covalent depending on the type of bond forming them. i.) Fe2(SO4)3 ___ ionic ____ iv.) NF3 ______ covalent ______ ii.) CO ____ covalent _____ v.) Zn(NO3)2 _____ ionic _____ iii.) Ag2Cr2O7 ____ ionic ___ vi.) SiO2 _____ covalent _____ 11.) What is the definition of “valence electrons”? Valence electrons are the electrons found in the outer shell of an atom that are used to form bonds by donating them or sharing them. 12.) Why do we care so much about valence electrons? Valence electrons are used to form bonds. 13.) When do electrons pair? Electrons pair only after the shell is half full. Then they spin pair to maximize the distance between each electron as they repel each other. 14.) Draw the following elements or compounds as Lewis structures. Sodium Sodium Chloride .. [Na]+1 [:Cl:]-1 . Na .. Carbon Dioxide .. .. :O::C::O: Fluorine .. .. :F: .. 15.) MgCO3 BCl3 Al(OH)3 Ca(OH)2 Ag2S Ce2S FeI2 CCl4 Cu2O H2 Sn(NO3)4 CS2 ZnBr2 Be(NO3)2 Ni2O3 NaHCO3 Ru2S3 H2O Ti2O3 La2O3 . KEY Dihydrogen Oxide Aluminum oxide Lead (II)iodide Carbon dioxide Magnesium chloride Silicon dioxide Sodium oxide nitrogen dioxide Mercury (II) chloride Sulphuric acid Silver oxide Sodium chlorate Sodium phosphate Gold (III) chloride Calcium carbonate Bismuth (V) chloride Iron (II) carbonate Rubidium nitride Yttrium bromide Barium nitrate 16.) Balance the following reactions. 2 2 2 2 2 3 2 2 7 2 3 4 2 6 2 2 2 2 6 6 2 2 2 2 2 6 17.) Write the names of the products expected in each of the following reactions, and classify each KEY reaction into one of the six types discussed in the chapter. i) the reaction between magnesium and oxygen magnesium oxide (synthesis) ii) the conversion of calcium nitride into its elements calcium + nitrogen (decomposition) iii) the reaction between sodium and water sodium hydroxide + hydrogen (single replacement) iv) the reaction between nitric acid and magnesium hydroxide magnesium nitrate + water (neutralization) v) the reaction between potassium chromate and silver nitrate silver chromate + potassium nitrate (double replacement) 18.) Assume that the formula for candle wax is C26H54. Write a balanced formula equation for the combustion reaction that occurs when a candle burns. 2 C26H54 + 79 O2  52 CO2 + 54 H2O 19.) List four methods of increasing reaction rates, and indicate how each is thought to work. 1.) Increase reactant concentration(s): this increases the number of reactant collisions. 2.) Increase reactant concentration(s): this increases the number of reactant collisions. 3.) Increase reactant temperature: this increases the number and intensity of reactant collisions. 4.) Add a catalyst: this causes the reactants to align better with one another prior to collision. 20.) List 4 household substances, 2 of which are acidic and 2 of which are basic Acidic – milk, citrus fruits, pop. Basic – baking soda, eggs, bleach, soap. 21.) Pick two indicators from your data booklet or textbook. Describe how each indicator would identify whether the solution was acid or base. 1.) Methyl Orange – red for acids (below 4) and yellow above 4. 2.) Phenothphthalein – colorless for acids (up to 10) and vivid pink for bases. 22.) a.) Describe how you would identify an organic and inorganic compound. Organic compounds always contain carbon and usually hydrogen. However, there are carbonates, carbides and carbon oxides that contain carbon and are not organic. To identify organic look for the high carbon content with hydrogen and it can’t be a carbide, carbonate or carbon oxides. b.) Give three examples of common organic compounds, one of which is an acid, and two compounds containing carbon that are not organic. Acetic acid – CH3COOH is an organic acid. Carbonates – CaCO3 and carbides – WC3 are not organic but contain carbon. KEY