REACTIONS of COMMON SUBSTANCES
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This experiment uses the computer program REACT.
The computer prints out an experiment sheet, accepts data and grades results.

Metathesis (Double decomposition)  CaCl2 + Na2CO3 ----> CaCO3(solid) + 2 NaCl
Calcium Chloride, CaCl2, is sold to melt ice in winter. It will melt ice at lower temperatures than regular salt, NaCl. You will also find it as an ingredient in canned food, where it replaces salt.
Sodium Carbonate, Na2CO3, also known as Washing Soda or Soda Ash, is used in laundry products to improve the cleaning power of the detergent. It does this by precipitating the calcium and magnesium ions as carbonates. This keeps the soap from precipitating. Precipitated calcium stearate is "soap scum".

CaCl2 + 2 NaOOC(CH2)16CH3 ---> Ca(OOC(CH2)16CH3)2 (solid) + 2 NaCl
Sodium Stearate, NaC18H35O2
, is a common ingredient in soap. The insoluble calcium salt forms bathtub rings.

Acid Base Neutralization   NH3(H2O) + CH3COOH ----> NH4C2H3O2 + H2O
Ammonia,
NH3, household ammonia is a 5% solution of NH3 in water. It is used in cleaning where its basic properties help remove grease. Its volatility allows it to evaporate without leaving a residue.
Acetic Acid, HC2H3O2; Vinegar is a 5% solution of this acid in water. Acids generally have a sour taste.

Decomposition 2 NaHCO3 ----> Na2CO3 + CO2 (gas) + H2O
Sodium Bicarbonate, NaHCO3,
also known as Baking Soda or Bicarbonate of Soda, is used as a leavening in baking, in deodorizing etc. Its many common uses reflect four things.
1. Availability at low cost; 2. Safely neutralizes acids; 3. Low toxicity; 4. Produces CO2 upon adding acid or heating.

Redox     NaClO + 2 KI + H2O ----> I2 + NaCl + 2 KOH
Sodium Hypochlorite,
NaClO, is the active ingredient in a "chlorine bleach". These bleaches contain about 5% of the hypochlorite. Bleaching involves the oxidizing power of sodium hypochlorite. See what happens when you add bleach to an organic dye.
Potassium Iodide, KI,
is not a common household chemical but is sometimes added to table salt ("iodized salt"). Iodine is necessary to produce thyroxin, the thyroid gland hormone.

Disproportionation  2 H2O2 ----> 2 H 2O + O2(gas)
Hydrogen Peroxide, H2O2
, is used as an antiseptic on cuts and scrapes and in hair care and bleaching. It releases Oxygen. The hydrogen peroxide you buy in a supermarket is a 3% solution.

Addition Ce(solid) + O2 ----> CeO2
Cerium metal, Ce,
while not a household word is a relatively frequently used metal. It is the "flint" in most lighters and you will use it today to light your burner. In a lighter, a steel file grinds off a small fresh piece of cerium metal. This immediately oxidizes in air generating heat and light.

"Sequential" (Combination of Metathesis and Decomposition)
CaCO3 (solid) + 2 HCl ----> CaCl2 + "H2CO3"
Calcium carbonate, CaCO3, occurs naturally as the rocks limestone and marble, the mineral calcite and as clam shells. The chalk you use to write on blackboards is partly CaCO3. It is also used medicinally as an antacid to neutralize excess acid (HCl) in the stomach, i.e. TUMS. This reaction also explains why acid rain is so destructive to marble buildings or statues.
Hydrogen Chloride, HCl, is a gas. When dissolved in water, it ionizes and is called Hydrochloric acid. It is sold in hardware stores as Muriatic Acid for treatment of concrete before painting.

The "carbonic acid", "H2CO3", formed in the reaction then decomposes to carbon dioxide a gas which bubbles out of solution. Water is also formed.
"H2CO3" ----> H2O + CO2 (gas)

There is a DATA SHEET