Unit 1 Physical Science: Chemical Reactions

Transcription

1 Unit 1 Physical Science: Chemical Reactions The physical sciences are concerned with the study of inanimate natural objects. Chemistry is the study of matter, its properties, how and why substances combine or separate to form other substances, and how substances interact with energy.

2 Periodic Table of the Elements The periodic table of the elements is a structured arrangement of elements. Elements are ordered by their atomic number, electron configurations and recurring physical and chemical properties. Copy of Periodic Table

3 Chemical Symbols A chemical symbol is an abbreviation of the name of an element. The names and symbols come from various sources (ie/ Greek and Latin).

4 Pun a play on words Periodic Table Puns

5 Exercise Periodic Table Puns

6 Periodic Table of the Elements Chemical Periods and Groups Elements in the periodic table are arranged in periods (rows) and groups/families (columns). main group elements metals nonmetals metalloids main group elements alkali metals transition elements alkaline earth metals halogens 18 noble gases 6 7 lanthanides actinides

7 Periodic Table of Elements

8 Characteristics of Metals and Nonmetals (There are exceptions.) Metals generally solids hard and nonbrittle good conductors of heat and electricity ductile and malleable melting points and boiling points are generally high generally lustrous and can be polished Nonmetals found in all three states hard but brittle bad conductors of heat and electricity neither ductile nor malleable melting points and boiling points are generally low generally non lustrous and cannot be polished

9 Atoms and Their Structure Atoms are the basic building blocks of matter. They are made up of smaller particles called subatomic particles. There are 3 subatomic particles: 1) protons found in the nucleus of the atom have a positive charge 2) neutrons found in the nucleus of the atom are electrically neutral (no charge) 3) electrons found in orbits (energy levels) around the nucleus have a negative charge structurestandard atomic notaion and bohr rutherford diagrams

10 Atomic Number The atomic number of an element gives us the number of protons in an atom of that element. Atomic Number Symbol Relative Atomic Mass Element Name 1 H Hydrogen +1 Ionic Charge In an atom: # protons = # electrons

11 Reminder: Bohr Diagrams Li atomic number = 3 Mg atomic number = 12 Li Mg O atomic number = 8 P atomic number = 15 O P

12 Ions Atoms may lose or gain electrons to form ions in which the number of electrons is different from the number of protons. The numerical value of the electric charge of an ion with a plus (+) or minus ( ) sign is called ionic charge. Metals tend to lose electrons to produce cations (positive ions) and nonmetals tend to gain electrons to produce anions (negative ions). Li atomic number = 3 Mg atomic number = 12 Li Mg O atomic number = 8 P atomic number = 15 O P

13 Periodic Table of Ions

14 Worksheet Chemistry: Ions and Subatomic Particles

15 Naming Monatomic Ions Simple cations are named by giving the element name and adding the word "ion". Na 1+ > Mg 2+ > Simple anions are named by dropping the ending off the element name, adding "ide" then "ion". F 1 > O 2 > N 3 >

16 Worksheet #1 Monatomic Ions

17 Assignment Your Name in Chemical Symbols N a n c y S h e r r a r d Chester Smith

18 Ionic Bonds When electrons are transferred from a metal to a nonmetal, an ionic bond results between the cation and anion.

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20 Simple Binary Ionic Compounds Ionic compounds are formed by the combination of a cation and an anion and are electrically neutral. Binary compounds are compounds that contain only two elements. Examples: Na Cl name chemical formula Al P name chemical formula Na O name chemical formula Al Cl name chemical formula Mg P name chemical formula Al O name chemical formula

21 Polyatomic Ions Polyatomic ions contain two or more different atoms. The atoms stay together as a single, charged unit. Endings to look for: "ate", "ite" nitrate NO 3 nitrite NO 2 chlorate ClO 3 chlorite ClO 2 sulfate SO 4 sulfite SO 3 acetate CH 3 COO or CH 3 CO 2 or C 2 H 3 O 2 hydrogen carbonate or bicarbonate HCO 3 Note: hydroxide OH cyanide CN peroxide O 2 Note: ammonium NH 4 See your periodic tables for more examples.

22 Ionic Compounds Containing Polyatomic Ions Like binary ionic compounds, ionic compounds containing polyatomic ions are electrically neutral. When more than one polyatomic ion is required in an ionic compound, parentheses are used to enclose the ion with the subscript going outside the parentheses > ( ). Write the correct name for: 1) AlPO 4 2) KNO 2 3) Ba(HCO 3 ) 2 4) Mg(OH) 2 5) (NH 4 ) 2 SO 4

23 Worksheet #3 Ionic Compounds Containing Polyatomic Ions

24 Transition Elements Transition elements are located in the middle of the periodic table.

25 Multivalent Metals and Their Ions Many transition elements can form more than one ion. These elements are called multivalent metals. Valence electrons are the electrons in the outer shell of an atom. They are the ones involved in forming bonds. Remember: Li atomic number = 3 Mg atomic number = 12 Li Mg

26 26 Fe iron most common ion When naming the ions of multivalent metals, you must include a roman numeral. The roman numeral is equal to the charge on the ion. I II III IV V VI VII VIII IX X Fe 2+ = iron (II) ion Pb 4+ = lead (IV) ion Cr 3+ = chromium (III) ion

27 Ionic Compounds Involving Multivalent Metals Write chemical formulas for the following: 1. nickel (II) oxide 2. titanium (III) fluoride 3. lead (IV) sulfide 4. cobalt (III) nitrate 5. manganese (III) sulfate

28 Write the names of the following compounds: 1. SnCl 4 2. TiO 2 3. Fe 2 O 3 4. Ni 2 (CO 3 ) 3 5. Nb(NO 3 ) 5

29 Worksheet #4

30 Recap Types of Ions Identify each of the following as a monatomic ion (MI), a polyatomic ion (PI), or the monatomic ion of a multivalent metal (MIMM), by printing MI, PI or MIMM on the line provided. PO 4 3 iron (II) ion fluoride ion Cu + sulfite ion Ca 2+ cyanide ion potassium ion PI MIMM MI MIMM PI MI PI MI

31 Worksheet #5 Ionic Compounds Summary Simple Binary Ionic Compound Ionic Compounds Containing Polyatomic Ions Ionics Compounds Containing Multivalent Metals Ionic Compounds Containing Polyatomic Ions and Multivalent Metals

32 Covalent Bonds A covalent bond is a chemical bond that involves the sharing of one or more electron pairsbetween two nonmetals or between a nonmetal and a metalloid. Two or more atoms held together by covalent bonds are called molecular compounds, covalent compounds or molecules. 20Project%20Page.htm The Hindenburg (1937) was an airship or "air blimp" that was filled with the highly flammable and combustible hydrogen gas, rather than an inert, non flammable gas, such as, helium.

33 Diatomic Molecules H 2, N 2, O 2, F 2, Cl 2, Br 2, I transition elements Other Special Molecules molecular phosphorous > P 4 molecular sulfur > S 8 NOTE: element symbol ion symbol molecular formula

34 Naming Binary Molecular Compounds Chemists use prefixes to indicate the number of atoms in each compound. Prefixes are necessary because atoms can combine in any whole number ratio. Learn the prefixes below. # of Atoms Prefix mono di tri tetra penta hexa hepta octa nona deca When naming binary molecular compounds, the first element name is given followed by the second element with an "ide" ending. The first element gets a prefix when there is more than one atom in the compound. The second always gets a prefix. Compound NO N 2 O NO 2 N 2 O 3 N 2 O 5 Name nitrogen monoxide dinitrogen monoxide nitrogen dioxide dinitrogen trioxide dinitrogen pentaoxide Common Names organic compounds H 2 O water or H 2 O 2 hydrogen peroxide or NH 3 ammonia or CH 4 methane or C 2 H 6 ethane or C 3 H 8 propane or C 4 H 10 butane or

35 Practice: Binary Covalent Compounds

36 Recap: Types of Compounds Types of Compounds Ionic Compounds transfer of electron(s) creates an ionic bond Molecular (Covalent) Compounds sharing of electron pair(s) creates a covalent bond metallic ion + nonmetallic ion metallic ion + polyatomic ion NH nonmetallic ion nonmetal + nonmetal metalloid + nonmetal nonmetal + metalloid NH polytomic ion

37 Worksheet Mixed Ionic/Covalent Compounds #1 Worksheet Mixed Ionic/Covalent Compounds #2 (Optional)

38 Counting Atoms NaCl Na Cl MgF 2 Mg F K 3 PO 4 K P O Sr(OH) 2 Sr O H Al 2 (SO 4 ) 3 Al S O 2RbI Rb I 4Ca 3 P 2 Ca P 3Zn(NO 3 ) 2 Zn N O

39 Worksheet: Counting Atoms in Compounds

40 Chemical Reactions A chemical reaction is a process that leads to the transformation of one set of chemical substances to another. substance + substance substance + substance

41 Conserving Mass The Law of Conservation of Mass states that, in a chemical reaction, the total mass of the reactants is always equal to the total mass of the products.

42 Balancing Chemical Reactions 1. N 2 + H 2 NH 3 Reactants Products N H N H 2. P 4 + O 2 P 2 O 3 Reactants Products 3. K + MgBr 2 KBr + Mg Reactants Products 4. FeCl 3 + NaOH Fe(OH) 3 + NaCl Reactants Products

43 Worksheet Balancing Chemical Reactions

44 Types of Chemical Reactions 1. Formation/Synthesis Reactions 2. Decomposition Reactions 3. Single Replacement/Displacement Reactions 4. Double Replacement/Displacement Reactions 5. Combustion Reactions

45 Formation/Synthesis Reactions General Formula A B A B substance substance compound

46 Example #1 Word Equation: hydrogen + oxygen water Chemical Equation:

47 Example #2 Word Equation: beryllium + chlorine beryllium chloride Chemical Equation:

48 Decomposition Reactions General Formula A B A B compound substance substance

49 Example #1 Word Equation: hydrogen peroxide water + oxygen Chemical Equation:

50 Example #2 Word Equation: lithium nitride lithium + nitrogen Chemical Equation:

51 Worksheet: Formation and Decomposition Reactions

52 Single Replacement/Displacement Reactions General Formula A B C A C B m m nm m nm m A B C B A C nm m nm m nm nm

53 Example #1 Word Equation: potassium + aluminum fluoride potassium fluoride + aluminum Chemical Equation:

54 Example #2 Word Equation: nitrogen + strontium oxide strontium nitride + oxygen Chemical Equation:

55 Example #3 Word Equation: magnesium + silver nitrate magnesium nitrate + silver Chemical Equation:

56 Double Replacement Reactions General Formula A B C D A D C B m nm m nm m nm m nm

57 Example #1 Word Equation: sodium fluoride + barium oxide sodium oxide + barium fluoride Chemical Equation:

58 Example #2 Word Equation: aluminum bromide + silver phosphide aluminum phosphide + silver bromide Chemical Equation:

59 Example #3 Word Equation: lead (II) nitrate + potassium iodide lead (II) iodide + potassium nitrate Chemical Equation:

60 Combustion Reactions General Formula hydrocarbon + oxygen carbon dioxide + water

61 Example #1 Word Equation: methane + oxygen carbon dioxide + water Chemical Equation: CH 4 + O 2

62 Example #2 Word Equation: butane + oxygen carbon dioxide + water Chemical Equation: C 4 H 10 + O 2

63 Worksheet Combustion Reactions

64 Questions re Chemical Reactions Answer the following questions about the chemical reaction shown below: 2H 2 + O 2 1. What are the reactant(s)? 2. What is the product(s)? 2H 2 O 3. What do we call the number "2" in front of the H 2 and H 2 O? 4. Is the reaction balanced? 5. How many hydrogen atoms are needed to produce two water molecules? 6. How many oxygen molecules are needed to produce two water molecules?

65 Worksheet Identifying Types of Reactions

66 Translating Word Equations to Balanced Chemical Equations 1. Potassium metal and chlorine gas combine to form potassium chloride. 2. Hydrogen gas and nitrogen monoxide react to form water and nitrogen gas. 3. Ammonium chloride and lead (III) nitrate react to form ammonium nitrate and lead (III) chloride. 4. Zinc and lead (II) nitrate react to form zinc nitrate and lead.

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68 Attachments Science 10 Grade 9 Chem Topics.docx Science 10 Grade 9 Chem What Do You Know.docx Science 10 Activity Molecular Models.docx Science 10 Answer Key Ions and Subatomic Particles.pdf Science 10 What Do You Know.docx