What household item is a pure substance?

Answer 1

There are not many household chemicals that meet the standard of being pure. You could answer using most of the following if you don't mind the small quantities of impurities that have been added:

• Distilled water=has carbon dioxide dissolved in it and the plastic from the jug can sometimes be tasted.
• Table salt=usually not 100% sodium chloride because magnesium compounds are usually added to prevent clumping as well as iodine compounds.
• Aluminum foil=has magnesium added to make it tougher.
• Lye=probably about as pure sodium hydroxide as you will find before it is opened. Carbon dioxide reacts with it to form sodum carbonate and it readily absorbs water vapor. It is good for cleaning drains and making hominy--it is rare to find it any more in most households.
• Pure Wesson Oil=isn't. It is a mixture of many different carbon length molecules that all behave similarly.
• Ice=fairly pure because as ice crystals freeze they exclude contaminants from the crystal lattice...the impurities are not gone, they just get pushed to the bottom of the icecube tray.
• Natural gas=mostly methane but 'stink' is added so you can tell if you have a leak.
• Copper=fairly pure. You will find it in the wiring and on the bottoms of some cookware.
• Tungsten=fairly pure. It is in your light bulbs.
• Window glass=mostly silicon dioxide. Tinted glass has impurities.