acetic acid (CH3COOH + H2O)
Weak acetic acid (~5%) is sold in grocery stores as white vinegar.

acetone (CH3COCH3)
Acetone is found in some nail polish removers and some paint removers. It may sometimes be found labelled as pure acetone.

aluminum (Al)
Aluminum foil (grocery store) is pure aluminum. So is the aluminum wire and aluminum sheeting sold at a hardware store.

aluminum potassium sulfate (KAl(SO4)2•12H2O)
This is alum that is sold at a grocery store.

ammonia (NH3)
Weak ammonia (~10%) is sold as a household cleaner.

ammonium carbonate [(NH4)2CO3]
Smelling salts (drug store) are ammonium carbonate.

ammonium hydroxide (NH4OH)
Ammonium hydroxide may be prepared by mixing household ammonia (sold as a cleaner) and strong ammonia (sold in some pharmacies) with water.

ascorbic acid (C6H8O6)
Ascorbic acid is vitamin C. It is sold as vitamin C tablets in the pharmacy.

boric acid (H3BO3)
Boric acid is sold in pure form as a powder for use as a disinfectant (pharmacy section) or insecticide.

butane (C4H10)
Butane is sold as lighter fluid.

calcium carbonate (CaCO3)
Limestone and calcite are calcium carbonate. Eggshells and seashells are calcium carbonate.

calcium chloride (CaCl2)
Calcium chloride can be found as a laundry booster or as a road salt or de-icing agent. If you are using the road salt, be sure it is pure calcium chloride and not a mixture of various salts.

calcium hydroxide (Ca(OH)2)
Calcium hydroxide is sold with garden supplies as slaked lime or garden lime to reduce soil acidity.

calcium oxide (CaO)
Calcium oxide is sold as quicklime at builder supply stores.

calcium sulfate (CaSO4 * H2O)
Calcium sulphate is sold as plaster of Paris in craft stores and building supply stores.

carbon (C)
Carbon black (amorphous carbon) can be obtained by collecting soot from the complete burning of wood. Graphite is found as pencil ‘lead’. Diamonds are pure carbon.

carbon dioxide (CO2)
Dry ice is solid carbon dioxide, which sublimates into carbon dioxide gas. Several chemical reactions evolve carbon dioxide gas, such as the reaction between vinegar and baking soda to form sodium acetate.

copper (Cu)
Uncoated copper wire (from a hardware store or electronics supply store) is extremely pure elemental copper.

copper(II) sulfate (CuSO4) and copper sulfate pentahydrate
Copper sulfate may be found in certain algicides (Bluestone™) at pool supply stores and sometimes in garden products (Root Eater™). Be sure to check the product label, since many different chemicals may be used as algicides.

helium (He)
Pure helium is sold as a gas. If you only need a little, simply purchase a helium-filled balloon. Otherwise, gas supplies usually carry this element.

iron (Fe)
Iron skillets are made of elemental iron. You can also pick up iron filings by running a magnet through most soils.

lead (Pb)
Elemental lead metal is found in lead fishing weights.

magnesium sulfate (MgSO4 * 7H2O)
Epsom salts, usually sold at a pharmacy, are magnesium sulfate.

mercury (Hg)
Mercury is used in some thermometers. It is more difficult to find than in the past, but many home thermostats still use mercury.

naphthalene (C10H8)
Some mothballs are pure naphthalene, though check the ingredients since others are made using (para)dichlorobenzene.

propane (C3H8)
Propane as sold as a gas barbeque and blow torch fuel.

silicon dioxide (SiO2)
Silicon dioxide is found as clean sand, which is sold at garden and building supply stores. Broken glass is another source of silicon dioxide.

potassium chloride
Potassium chloride is found as lite salt.

sodium bicarbonate (NaHCO3)
Sodium bicarbonate is baking soda, which is sold in grocery stores. sodium chloride (NaCl)
Sodium chloride is sold as table salt. Look for the uniodized variety of salt.

sodium hydroxide (NaOH)
Sodium hydroxide, also known as Lye, is a strong base that may sometimes be found in solid drain cleaner (Red Devil Lye™). The pure chemical is waxy white solid, so if you see other colors in the product, expect that it contains impurities.

sodium tetraborate decahydate or borax (Na2B4O7 * 10H2O)
Borax is sold in solid form as a laundry booster, all-purpose cleaner and sometimes as an insecticide.

sucrose or saccharose (C12H22O11)
Sucrose is ordinary table sugar. White granulated sugar is your best bet. There are additives in confectioner’s sugar. If the sugar is not clear or white then it contains impurities.

sulfuric acid (H2SO4)
Car battery acid is about 40% sulfuric acid. The acid can be concentrated by boiling it, though it may be heavily contaminated with lead, depending on the state of the battery’s charge when the acid was collected.

zinc (Zn)
Zinc blocks may be sold by some electronics supply stores for use as anode. Zinc sheets may be sold as roof flashing at some building supply stores.