1. Review

2. titanium (lll) oxide trihydrate
Ti2O3 · 3 H2O
titanium (lll) oxide trihydrate

3. hydrobromic acid
HBr

4. chloric acid
HClO3

5. dicarbon hexachloride
C2Cl6

6. nitrous acid
HNO2

7. HF
hydrofluoric acid

8. Chemical Reactions

9. 2.0 - Systems What are chemical reactions?
new products are formed with new properties
some bonds are broken and some new chemical bonds are formed
atoms are rearranged

10. Physical Change Chemical Change
intramolecular
bond
intermolecular
bond

11. When we study reactions, we talk about systems
system: part of the universe being studied
closed system: things cannot enter or leave the system
matter

12. Closed System

13. Closed System

14. When we study reactions, we talk about systems
system: part of the universe being studied
closed system: things cannot enter or leave the system
open system: things can enter or leave the system
matter

15. Open System

16. Chemical reactions in closed systems ALWAYS follow four basic laws:
The Law of Conservation of Mass: the total mass in a reaction does not change
The Law of Conservation of Atoms: the total # and type of atoms does not change
The Law of Conservation of Electrical Charge: the total electrical charge does not change
4. The Law of Conservation of Energy: the total energy does not change

17. Writing chemical reactions
Word equation: uses words to describe a reaction
solid copper (l) carbonate + water → carbon dioxide gas + copper (l) hydroxide

18. Writing chemical equations
Chemical equation: uses symbols, subscripts, and coefficients to describe a reaction
reactants
products
Cu2CO3(s) + H2O(l) → CO2(g) + 2 CuOH(aq)
subscripts
phase
coefficient

19. Pb2+(aq) + I-(aq) → PbI2(s)
Phase Symbols
phase symbols: symbols that tell you what phase the reactants and products are in
(s) = solid______________
(l) = liquid______________
(g) = gas______________
(aq) = aqueous______________
Pb2+(aq) + I-(aq) → PbI2(s)

20. There are 7 non-metals that exist in nature as diatomic molecules, or molecules with 2 atoms. These are typically gases. Whenever a reaction is done with these elements, the subscript is always 2!
HOFBrINCl

21. Balancing Equations
the four conservation laws must be expressed when writing chemical reactions equations

22. ___Ca2C + ___O2 → ___ Ca + ___CO2
___Pb(NO3)2 + ___ NaI → ___PbI2 + ___ NaNO3
____ N2 + _____ H2 → _____NH3
____ KClO3 → ____ KCl + ____O2
____ NaCl + ____ F2 → ____ NaF + ____ Cl2
_____ H2 + ___ O2 → ____ H2O
_____ AgNO3 + ____ MgCl2 → ____ AgCl + ____ Mg(NO3)2
____ AlBr3 + ___K2SO4 → ___KBr + ___ Al2(SO4)3
____CH4 + ____ O2 → ____ CO2 + ____ H2O
____ C3H8 + ____ O2 → ____ CO2 + ____ H2O
____ C5H ____ O2 → ____ CO2 + ____ H2O
Challenge: ____ C19H17NO3 + ____ O2 →____ CO2 + ____ H2O + ____ N2 2 2 2 3 2 2 2 3 2 2 2 2 2 2 2 3 6 2 2 5 3 4 8 5 6 4 87 76 34 2

23. sodium ion reacts with sulfate ion to produce sodium sulfate
Step 1: Write the equation. Step 2: Balance the equation
Na+ + SO42-  Na2SO4
2Na+ + SO42-  Na2SO4

24. Boron mononitride reacts with fluorine to give boron trifluoride and nitrogen
BN F2  BF N2

25. Boron mononitride reacts with fluorine to give boron trifluoride and nitrogen
BN F2  BF N2 2 3 2

26. Solid sodium reacts with chlorine gas to produce solid sodium chloride.
Na(s) + Cl2(g)  NaCl(s) 2 2

27. H2O(l) + Na2O(s)  NaOH(aq)
Liquid water reacts with powdered sodium oxide to produce aqueous sodium hydroxide.
H2O(l) + Na2O(s)  NaOH(aq) 2

28. Types of Chemical Reactions

29. H2(g) + Cl2(g) → 2HCl(g)
AgNO3(aq) + NaCl → AgCl(s) + NaNO3(aq)
2Ag2O(s) → 4Ag(s) + O2(s)
C5H12 + 8O2(g) → 5CO2(g) + 6H2O(l)
Cl2(aq) + 2KI(aq) → I2(aq) + 2KCl(aq)
HCl(aq) + NaOH(aq) → H2O(aq) + NaCl(aq)

30. Types of Chemical Reactions
synthesis (or combination): A + B → AB
two or more elements combine to form a compound

31. Types of Chemical Reactions
synthesis (or combination): A + B → AB
two or more elements combine to form a compound

32. Types of Chemical Reactions
decomposition: AB → A + B
a single compound breaks down into simpler substances

33. Types of Chemical Reactions
decomposition: AB → A + B
a single compound breaks down into simpler substances

34. Types of Chemical Reactions
single replacement: A + BX → B + AX
an element reacts with a compound
one element replaces another

35. Types of Chemical Reactions
single replacement: A + BX → B + AX
an element reacts with a compound
one element replaces another

36. Types of Chemical Reactions
double replacement: AB + XY → AY + XB
two compounds react
two elements switch places

37. Types of Chemical Reactions
double replacement: AB + XY → AY + XB
two compounds react
two elements switch places

38. Types of Chemical Reactions
combustion: CaHbY + O2 → H2O + CO2
an organic compound (compound with C and H) reacts with O2 to produce heat, H2O, and CO2

39. Types of Chemical Reactions
combustion: CaHbY + O2 → H2O + CO2
an organic compound (compound with C and H) reacts with O2 to produce heat, H2O, and CO2

40. Types of Chemical Reactions
neutralization: HX + YOH → H2O + XY
an acid reacts with a base (molecule with OH) to produce water and salt