Summary Balancing chemical equations

BALANCING CHEMICAL EQUATIONS
you will be given a chemical reaction ,
and
you must
change it so that
the amount of of each element is sides
atoms
equal on both


Do this by increasing the number of reactants / products
(i. e. number before the chemical formulae)
adding a




why Matter
must equations be balanced?
cannot be created or destroyed so the atoms
you
start with must be the same atoms
you end with .




(Used for mole calculations)


HOW TO :




-

Make list of elements for both sides and
all how much of
each there is ( I 1 it )
-

Balance all elements one by one (excl 0 .
+ 1- 1)
-


Update lists of elements as you balance
Balance
oxygen
-




Tip :
Balance
hydrogen
-

Hi
THEmight
each element in its own colour .




•
Do a final check
makes it easier to see +
identify

to see steps
Don't have to keep rewriting just
-




EXAMPLES :


/
2 H 2- a ✓
Hz + Oz
-4
→
H20
-




1 .




-
Z o -
l -

z ✓


Hz + Oz -721-120
21-12+02 → ZH20

Na -
I -2
Ng -2 ✓

2 .
NaOH +
Hz 504 →
Naz 504 +
H20 5- i s -


I ✓

0-5-6 0-5-6 ✓

2Nd OH +
Hz 504 →
Naz 504 +
H20 µ -3-4 14--2-4 ✓



2Nd OH +
Hz 504 →
Naz 504 +
ZH20
N -

l -
Z N -
I -2 ✓


3. N Hall + Ca ( OH)z → Caclz +
NH3 + H20 ce -
I -2 I -2 ✓

Ja -
l ca
-

I ✓


2N Hall + Ca ( OH)z → Caclz +
NH3 + H20 o -
z o -



I -2 ✓

H -
6- 10 t -

S 8- to
-

✓

2N Hall +
Ca( OH)z →
Caclz +2MHz +
H20

2NH act +
Ca( OH)z →
Caclz +2MHz +
ZH20