Majority of the chemical reactions
encountered in the laboratory and those
that occur in our environment fall into
one of the following types:
1. Combination (synthesis) – It is the
reaction in which 2 or more
substances combine to form a single
product. The reactants may be
elements or compounds, but the
product is always a single compound.
2. Decomposition – It is the reaction in
which a single substance, usually a
compound, breaks down into 2 or
more substances which may be
elements or simpler compounds. There
is only a single reactant in a
decomposition reaction.
3. Single Replacement or Displacement or
Substitution – It is the reaction in which
one element reacts by taking the
place of another element in a
compound. This type of reaction
always has 2 reactants. To determine
which element will be displaced or
substituted, reference may be made
to the electromotive or activity series
or the observed chemical reactivities
of elements according to their
arrangement in the periodic table.
4. Double Replacement or Double
Decomposition or Exchange Reaction –
It is the reaction in which the positive
ion from one compound takes the
negative ion of another compound,
and the remaining ions also combine
to form another ionic compound. In
this reaction, 2 ionic compounds serve
as reactants.
What happens during chemical
reactions are represented by chemical
formulas and notations (+, -, and
signs) set up as symbolic sentences
known as chemical equations. A
chemical equation is not considered
valid until it is balanced.
BALANCED CHEMICAL EQUATION
A. 1.) 3Fe + O₂→ Fe₂O₃
TYPE OF REACTION
Combination or synthesis
2.) NaOH + CO₂→NaOHCO₃
B. 1.) [NH₄]₂CO₃→2NH₃+ H₂CO₃
H₂CO₃→H₂O +CO₂
2.) CoCl₆ 6H₂O → CoCl₆+6H₂O
3.) BaCl₂ 2H₂O→ BaCl₂+H₂O
Decomposition
C. 1.) CuSO₄ + Fe→ FeSO₄ + Cu
Single Replacement
2.) 2.2KL + 2Cl → 2KCl + I₂
D. 1.) NaCl+AgNO₃→ NaNO₃+AgCl
2.) KSCN+FeCl₃→ 3KCl+Fe[SCN]₃
Double Replacement
To distinguish among the different types
of chemical reactions.
2. To identify the reactants and products
of chemical reactions.
3. To develop skill in writing and balancing
equations.
1.
Blue and red litmus paper
 Bottle with cover
 Clay triangle
 Crucible tong
 Crucible with cover
 Evaporating dish
 Graduated cylinder
 Nail, 1inch

Softdrink straw
 Spatula
 Stirring rod
 Test tube holder
 Test tubes
 Tirril burner
 Triple beam balance
 Tripod
 Watch glass

Starch solution
 Chlorine water
 Distilled water
 Phenolphthalein
 0.01 M NaOH
 0.1 M KI
 0.1 M AgNO3
 0.1 M FeCl3

0.1 M KSCN
 0.1 M NaCl
 0.5 M CuSO4
 6.0 M HCl
 (NH4) 2CO3
 BaCl2 2H2O
 CoCl2 H2O

REACTANTS
OBSERVATIONS
A. 1.) Fe nail, dry, in covered bottle
Fe nail + moist, exposed
2.) H2O
+ NaOH + phenolphthalein
+ breath
pink in color
colorless
B. 1.) (NH4) 2CO3 odor
+ moist red litmus
became blue in color
+ moist blue litmus
as is
2.) CoCl2 6H2O
+ heat
3.) BaCl2 2H2O
Weight before heating _____ g
Weight after heating _____ g
Difference in weight _____ g
purple in color
became blue
decrease in weight
C. 1.) CuSO4 + Fe (nail)
2.) KI + Cl2
+ starch
D. 1.) NaCl + AgNO3
rust
colorless
indigo in color
milky white in color; precipitate
formed at the bottom
2.) KSCN + FeCl3
E. 1.) HCl + magnesium ribbon
became bloody red in color
magnesium ribbon was dissolved
release of gas
1. What compound in your breath reacted
with the solution in A-2 that caused the
change in its color?
Answer: The compound that reacted
with the solution was the carbon dioxide.
2. What is the substance formed in the nail
in C-1? From this result, which is more
active iron or copper?
Answer: The substance formed was
the rust(ferrous sulfate). The more active
element was the iron.
3. What substance produced in the
reaction between chlorine water and Kl
was confirmed by its reaction with
starch?
Answer: The substance produced was
Iodine because the starch turned bluish black.
4. What is the chemical composition of the
precipitate formed when the sodium
chlorine solution was mixed with silver
nitrate solution?
Answer: A white precipitate was
formed after the mixture of NaCl and
AgNO₃.
GROUP VII
• Papillero, Micah
• Patricio, Deseree
• Paulo, Lea Carla
• Pitahin, Lynette
• Remorosa, Claudia Helena
GROUP VIII
• Roldan, Katherine
• Salonga, Emirenz Charmiane
• Santos, Jasmine
• Singh, Queencel Joyce
• Villanueva, Jengale