Download Balancing Chemical Equations Activity Name: Chemistry Date: Hour

Balancing Chemical Equations Activity
Chemistry
Name: ______________________________
Date: ____________________ Hour: ______
First, some practice:
How many atoms of each element are in the following:
3 P2 S5
________ P
________ S
5 HgCr2O7
________ Hg ________ Cr ________ O
4 C2H4O2
________ C
________ H
2 C8BrF17
________ C
________ Br ________ F
3 Fe(NH4)2(SO4)2 ________ Fe ________ N
________ O
________ H
________ S
________ O
Use the following to answer the questions below:
5 H2
1) What number represents the coefficient?
__________________
2) What number represents the subscript?
__________________
3) What element is represented by the letter H?
__________________
4) How many H atoms do you have?
__________________
Activity Procedure:
1) Using your set of cards, replicate the first chemical equation (listed in Table 1) on your
desk.
2) Label the reactant side and the product side.
3) Record the results into Table 1.
4) Identify the elements on the reactant side.
5) Count the number of atoms for each element.
6) Identify the elements on the product side.
7) Count the number of atoms on the product side.
8) Are the two sides equal? If not, the equation is not balanced.
9) The index cards numbered 2 - 7 are your coefficients. They can ONLY be placed in front
of the elements and compounds. You cannot change the subscripts.
10) Choose an element that is not balanced and begin to balance the equation.
11) Continue until you have worked through all the elements in the equation.
12) Once they are balance, count the final number of reactants and products.
13) Write the balanced equation.
14) Can your equation be simplified? If so, simplify it!
Table 1: Chemical Equations
Equation
Reactants
Products
Balanced Equation
H2 + O2 —> H2O
H2O2 —> H2O + O2
Na + O2 —> Na2O
NH3 —> N2 + H2
P4 + O2 —> P4O10
Fe + H2O —> Fe3O4 + H2
C + H2 —> CH4
Na2SO4 + CaCl2 —> CaSO4 + NaCl
C2H6 + O2 —> CO2 + H2O
Al2O3 —> Al + O2
Post-Activity Questions:
1) What does —> mean? __________________________________________________________________________________
2)
What side of the equation are the reactants found? ______________ products? ______________
3)
Why must all chemical equations be balanced? _______________________________________________________________
_____________________________________________________________________________________________________
4)
Why can’t the subscripts be changed? ______________________________________________________________________
5)
What does it mean to “simplify” the equation? _______________________________________________________________