Sem 1 09-10 Final Review Regular Chem

1 When elements combine to form substances consisting of two or more different atoms

1a chemical compounds

2 H2SO4 How many different elements?

2a 3

3 H2SO4 How many total atoms of elements?

3a 7

4 1st energy level holds ? e- 2nd holds ? e-

4a 2 8

5 Charged particles are called ?

5a Ions -

6 Bonds that share electrons are called ?

6a Covalent Bonds

7 The elements or compounds that enter the reaction are called -

7a Reactants

8 Elements or compounds produced in a chemical reaction are called -

8a Products

9 reactants -----> products What does the arrow mean?

9a To make or to yield

10 Balance H2 + O2 -----> H2O Write the sum of the coefficients

10a 2 H2 + O2 -----> 2 H2O Sum of coefficients is 5 (2+1+2)

Fe2O3 + CO -----> Fe3O4 + CO2 11 Balance Fe2O3 + CO -----> Fe3O4 + CO2 Find the sum of coefficients

3 Fe2O3 + CO -----> 2 Fe3O4 + CO2 11a 3 Fe2O3 + CO -----> 2 Fe3O4 + CO2 Sum of coefficients is 7 (3+1+2+1)

Hydrogen and chlorine react to produce hydrochloric acid 12 Hydrogen and chlorine react to produce hydrochloric acid Change to a balanced equation (remember boot elements are diatomic)

12a H2 + Cl2 -----> 2HCl

13 What type of reaction is this?

13a Combination/synthesis

14 Type of reaction

14a decomposition

15 Zinc plus iodine makes zinciodide Write the balanced equation

15a Zn + I2  ZnI2

16 Write the balanced equation for the decomposition of water

16a 2 H2O  2 H2 + O2

17 Write the single displacement reaction that makes sodium hydroxide and a gas from sodium and water

17a 2 Na + 2 H2O  2 NaOH + H2

18 Sr2+ has how many protons, neutrons and electrons?

18a 38 protons, 50 neutrons, and 36 electrons.

19 A certain metallic element forms a compound with chlorine, having the general formula XCl2. The X ion in this compound has 28 electrons. What is element X

19a Zn

20 Elements belonging to which group of the periodic table form ions with a 2+ charge?

20a Alkaline Earth Metals

21 An ion with a positive charge is called a ___________;a negatively charged ion is called an___________

21a cation (pronounced CAT-ion); anion (AN-ion).

22 Give the complete chemical symbols for the following ions: (a) The ion with 26 protons, 30 neutrons, and 24 electrons; (b) the phosphorus ion with 16 neutrons and 18 electrons.

22a (a) The element whose atoms have 26 protons (atomic # 26) is Fe (iron). The mass number of this isotope is 26 + 30 = 56 (the sum of the protons and neutrons). Because the ion has two more protons than electrons, it has a net charge of 2+. Thus, the complete symbol for the ion is 56Fe2+ (b) By referring to a periodic table or table of elements, we see that phosphorus (symbol P) has an atomic number of 15. Thus, each atom has 15 protons. The mass number of the ion is 15 + 16 = 31. Because the ion has 15 protons and 18 electrons (three more electrons than protons), its net charge is 3-. Thus, the complete symbol for the ion is 31P3-

23 polyatomic ions are (give an example as well as a definiton)

23a These ions consist of atoms joined as in a molecule, but they have a net positive or negative charge Ex: NO3– (nitrate ion) & SO42– (sulfate ion).

24 atoms gain or lose electrons so as to end up with the same number of electrons as

24a the noble gases

25 Predict the charges expected for the most stable ions of barium and oxygen.

25a Ba 2+ cation. O 2- anion

26 Predict the charge of the most stable ion of aluminum

26a Al 3+

27 Which elements are considered diatomic list them

27a Boot elements H2 N2 O2 F2 Cl2 Br2 I2 At

28 Which of the following compounds would you expect to be ionic: N2O, Na2O, CaCl2, SF4?

28a We would predict that the ionic compounds are Na2O and CaCl2 because they are composed of a metal combined with a nonmetal. The other two compounds, composed entirely of nonmetals, are molecular.

29 Which of the following compounds are molecular: CCI4, FeS, P4O6, PbF2?

29a CCI4 and P4O6 These are non-metals. FeS has an electronegativity difference that puts it in the polar covalent range.

30 What are the empirical formulas of the compounds formed by (a) Al 3+ and Cl – ions (b) Al 3+ and O2- ions (c) Mg 2+ and NO3 – ions?

30a (a) Three Cl– ions are required to balance the charge of one Al3+ ion. Thus, the formula is AlCl3. (b) Two Al3+ ions are required to balance the charge of three O2– ions (that is, the total positive charge is 6+, and the total negative charge is 6-). Thus, the formula is Al2O3. (c) Two NO3– ions are needed to balance the charge of one Mg2+. Thus the formula is Mg(NO3)2. In this case the formula for the entire negative ion must be enclosed in parentheses so that it is clear that the subscript 2 applies to all the atoms of that ion.

31 (a) Na + and PO4 3– (b) Zn 2+ and SO4 2– (c) Fe 3+ and CO3 2–

31a (a) Na3PO4; (b) ZnSO4; (c) Fe2(CO3)3

32 How many hydrogen atoms are in CH3CH(CH3)2?

32a 10

33 Which of the following are ionic and which are molecular? K2O CCl4

33a All are either polar covalent (molecular) or covalent (molecular) except K2O is ionic.

34 Which of the following compounds is not an ionic compound?   NaF2  SrO  GaF3  Cs2O  CsCl

34a All are ionic

35 Which of the following is incorrectly named, using the rules for binary molecular compounds? CF4--carbon tetrafluoride  SbCl3--antimony trichloride  C2O5--dicarbon pentoxide  H3As--hydrogen arsenide  NO2--nitrogen dioxide

35a Trihydrogen arsenide would be correct

36 Which of the following is named correctly? barium chloride pentahydrate, BaCl2 6H2O  lithium sulfate, Li2SO3  potassium nitrate, KNO2  sodium chlorite, NaClO

36a barium chloride pentahydrate, BaCl2 6H2O 

37 Which of the following statements is incorrect? Salpeter, KNO3, is really potassium nitrate.  Milk of magnesia, Mg(OH)2, is really magnesium hydroxide.  Muriatic acid, HCI, is really hydrochloric acid.  Lime, CaO, is really calcium oxide.  Soda ash, Na2CO3, is really sodium carbonite.

37a Soda ash, Na2CO3, is really sodium carbonite

38 Which of these acids has a name that begins with hydro? HCl  HClO3  HClO2  HClO4  HClO

38a HClO

39 Which name is incorrectly matched with the given formula? SO2 : dioxygen sulfide  P2O5 : diphosphorus pentoxide  CO2 : carbon dioxide  H2O : dihydrogen oxide  NH3: nitrogen trihydride

39a SO2 : dioxygen sulfide 

40 Draw the dot diagram for CH2ClF

40a

41 Draw the dot diagram for C2H4

41a

42 Draw the dot diagram for H3PO4

42a

43 Draw the dot diagram for SO4 2-

43a 2-

44 Name this compound CCl4

44a Carbon Tetrachloride

45 Name this compound H2SO3

45a Chlorous acid