1. BALANCING CHEMICAL REACTIONS: How do we get out what we put in?
LAB
BOOK?

2. Na3(PO4) + CaCl2 = Ca3(PO4)2 + NaCl
Zn + Pb(NO3)2 = Zn(NO3)2 + Pb
AlBr3 + Cl2 = AlCl3 + Br
Na3(PO4) + CaCl2 = Ca3(PO4)2 + NaCl
K (ClO3) = KCl + O2
Al + HCl = AlCl3 + H2
Ca (OH)2 + H3(PO4) = Ca3(PO4)2 + H2O
Cu + H2(SO4) = Cu (SO4) + H2O + SO2
H2 + NO = H2O + N2

3. Writing Formulas

5. SiO2 Fe2O3 H2SO4 Mg(OH)2 C7 H5(NO2)3 Ca(H2PO4)2 C4 H10 C12 H22O11
3 NO2 = 3N 6O
Ca(H2PO4)2
Ca = 1
2H2PO4 = 4H 2P 8O

8. In a balanced chemical equation, atoms are not lost or gained
Basic Chemistry Copyright © 2011 Pearson Education, Inc.

11. Coefficient X subscript = # of each atom
A. Na(s) + N2(g) → NaN3(s)
1Na Na
2N N not balanced
B. C2H4(g) + H2O(l) → C2H5OH(l)
2C C
6H H
1 O O . 2 3 2
Basic Chemistry Copyright © 2011 Pearson Education, Inc.

12. Coefficient X subscript = # of each atom

13. Equations with Polyatomic Ions
Basic Chemistry Copyright © 2011 Pearson Education, Inc.

14. Balancing Chemical Equations
STEP 1 Write an equation using the correct formulas
in the reactants and products.
MgCl2(aq) + Na3(PO4)1 (aq) NaCl(aq) + Mg3(PO4)2(s)
STEP 2 Count the atoms (or ions) of each element in the reactants and products.
Reactants Products
3Na Na+ not balanced
1 PO43 PO43 not balanced
1Mg Mg2+ not balanced
2Cl Cl not balanced

15. Balancing Chemical Equations
STEP 3 Use coefficients to balance each element.
3MgCl2(aq) + 2Na3(PO4)1 (aq) NaCl(aq) + 1Mg3(PO4)2(s)
STEP 4 Check the final equation for balance.
Reactants Products
6Na Na+
2PO43 PO43
3Mg Mg2+
6Cl Cl

16. Na3(PO4) + CaCl2 = Ca3(PO4) 2 + NaCl
Zn + Pb(NO3) 2 = Zn(NO3) Pb
AlBr3 + Cl2 = AlCl3 + Br
Na3(PO4) + CaCl2 = Ca3(PO4) 2 + NaCl
K (ClO3) = KCl + O2
Al + HCl = AlCl3 + H2
Ca (OH)2 + H3(PO4) = Ca3(PO4) 2 + H2O
Cu + H2(SO4) = Cu (SO4) + H2O + SO2
H2 + NO = H2O + N2

18. Lab book

19. Lab book