Name: ____________________________________________________ Date: ______________ Period: ____________
8.1 Practice Worksheet A
Balancing Equations
Part 1:
Why do scientists use chemical equations?
Chemical reactions can be represented with both word equations and formula equations.
A) Write a word equation for the following reaction:
2 Na + 2 H2O  2 NaOH + H2
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Word Equations give us qualitative / quantitative (circle one) information about a reaction.
B) Write a formula equation for the following reaction:
Aluminum bromide + potassium sulfate  Aluminum sulfate + potassium bromide
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Is the equation you wrote balanced (count up atoms making sure none were lost or gained)?
A balanced formula equation, gives us qualitative / quantitative information about a reaction.
Part 2: Practice making sure you can count atoms correctly in a compound:
1. KClO3
K: ___ Cl: ___ O: ___
4. 2 Ca(OH)2
Ca: ___ O: ___ H: ___
2. Ca(OH)2
Ca: ___ O: ___ H: ___
5. 3 C6H12O6
C: ____ H: ____ O: ___
3. (NH4)3PO4
N: ___ H: ___ P: ___ O: ___
To balance a chemical equation, use _____________________ at the beginning of each compound to
represent the correct amount of molecules needed conserve all atoms involved in the reaction; this is
known as following the ___________________________________________________________
Here are some tips for balancing
 Start by balancing atoms that only appear once on each side
 Balance ______________________ ions as units
 Balance _______ and ______ last
Part 3: Practice writing word equations where indicated and balance all equations:
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pure elements are named as themselves
compounds should be named according to ionic, covalent, or acid naming rules
6. ___H2(g) + ___O2(g) ___ H2O(g)
Word Equation: ____________________________________________________________________
7.
___ N2(g)
+ ___H2(g)  ___NH3(g)
Word Equation: ____________________________________________________________________
8. ___S8(g) + ___ O2(g)  ___SO3(g)
9. ___N2(g) + ___ O2(g)  ___N2O(g)
Word Equation: ____________________________________________________________________
10. ___HgO(s)  ___ Hg(l) + ___O2(g)
11. ___CO2(g) + ___ H2O(g)  ___ C6H12O6(g) + ___O2(g)
12. ___ Zn(s) + ___ HCl(aq)  ___ZnCl2(s) + ___H2(g)
Word Equation: ____________________________________________________________________
13. ___ SiCl4(s) + ___H2O(l) ___ H4SiO4(s) + ___ HCl(aq)
14. ___ Na(s) + ___H2O(l)  ___NaOH(aq) + ___H2(g)
15. ___H3PO4(aq)  ___H4P2O7(aq) + ___H2O(l)
16. ___C10H16(l) + ___Cl2(g)  ___ C(s) + ___ HCl(aq)
17. ___CO2(g) + ___NH3(l)  ___OC(NH2)2(l) + ___H2O(g)
18. ___Si2H3(aq) + ___O2(g) ___ SiO2(s) + ___H2O(l)
19. ___Al(OH)3(aq) + ___H2SO4(aq)  ___Al2(SO4)3(s) + ___ H2O(l)
Word Equation: ____________________________________________________________________
20. ___Fe(s) + ___O2(g)  ___ Fe2O3(s)