Evidence of chemical reactions
A chemical reaction to any process in which atoms, molecules orions of a substance is transformed into atoms, molecules or ions ofdifferent chemical and internaltransformation occurs.
A chemical reaction can be seen by several factors: color change,temperature change and change of state:
* Change color
There may be a change in color. It can be for awhile or stay with anew color
* Temperature Change
You can make a difference in the temperature increase ordecrease.
* Change of Status
There may be a change to solid, liquid or gas.
Types of chemical reaction
*Combination Reactions
A + B => AB
A and B are two items that together form a single product.
* Decomposition reactions
AB => A + B
AB is a compound that decomposes toform two products A and B
* Simple displacement reactions
A + BC => B + AC
A, B and C are substances, but B and C form a compound. In this type of reactionto dissociate NO substances before they weremade with each other and form a new one.
* Double displacement reactions
AB + CD => AD + CB
This occurs as in the previous section, but now are 2 compounds.May form: Precipitates, Gases
* Combustionreactions
Are reactions that burn producing carbon dioxide and water.
Objective
The student recognizes through experimental evidences some Chemicals properties of the following substances.Hypothesis
The reactions occur between compounds anre pure substance. This should change the composition of matter to be consider as a chemical reaction.
Materials and reactants
Beakers
Test tubesTest tube tongs
Spatula
Zinc Zn
Magnesium Mg
Copper Cu
Hydrochloric 6M HCl
Silver Nitrate 0.1M AgNO3
Barium Chloride BaCl2
Sodium Sulfate 0.1M Na2SO4
Lead (II) Nitrate 0.1MPb(NO3)2
Potassium Iodide 0.1M KI
Experimentation
Perform the following experiments:
a) Add 10 drops of HCl acido n a test tube. Using the tip of the spatula take a...
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