ChemMatters - How Sticky Innovations Changed the World

The introduction to this article describes what problem?

• Ammunition boxes used during WW2 were sealed with wax to waterproof them. They did not work as intended because the tape that was used tore off leaving the boxes sealed shut.

• Ammunition boxes used during WW2 were sealed with tap to waterproof them. They did not work as intended because the tape allowed the water to enter the box and damage the ammunition.

• Ammunition boxes used during WW2 were sealed with tap to waterproof them. They did not work as intended because the tape was too strong and the boxes often did not open.

• Ammunition boxes used during WW2 were sealed with wax to waterproof them. They did not work as intended because the tape that was used was too strong and the boxes where sealed shut.

The tape that Vesta Stoudt invented during WW2 was

• stronger than paper tape (i.e. would not tear like paper tape when pulled)

• stickier than paper tape

• weaker than paper tape (i.e. would tear easier than paper tape when pulled)

The tape that Vesta Stoudt invented during WW2 was originally called

• duck tape

• sticky tape

• hockey tape

• paper tape

Archaeological evidence suggests that glue goes back to

• about 300 years ago.

• about 1000 years ago.

• about 200,000 years ago.

Archaeological evidence suggests that glue goes back to the early-human and Neanderthal days. Starting as far back as 200,000 years ago during the Paleolithic Period, glue was likely made

• heating birch bark to make a sticky tar.

• heating animal fat to make a sticky tar.

• adding animal fat to birch bark and heating to make a sticky tar

According to the article which of the following statements about "tar" is INCORRECT?

• Tar is a natural polymer—that is, it consists of a large number of

  similar molecules (monomers) bonded together in long chains.

• Tar is thermoplastic, which means it softens when heated and solidifies as it cools.

• At room temperature, tar is solid, but when warmed it can be molded like putty.

• When heated tar is cooled, the tar hardens and can hold two things together.

• None of the other 4 statements are INCORRECT.

According to the arricle, which of the following statements about "limestone/calcium carbonate" is INCORRECT?

• The chemical formula of lime stone is CaCO₃ and is often

  composed of the skeletal remains of marine organisms.

• When heated, added to water, and mixed with sand,

  limestone produces lime mortar.

• When lime mortar reacts with carbon dioxide in the air, it hardens into limestone, binding together the materials it’s in

  contact with.

• Lime mortar was used to bond together stone in ancient structures, including the Egyptian pyramids and the Great Wall of China.

• None of the other 4 statements is INCORRECT.

According to the article today's adhesives are ______________ - based. (based has been used in this sentence to form adjectives showing the main place or area in which something or someone works, lives, or does business)

• Acrylate

• Calcium carbonate

• Chlorine

• Peptide

T/F - Producing polymers makes use of something called a polymerization reaction—that is, a large number of identical molecules, called monomers, react to form one single, large molecule, the polymer.

• True

• False

T/F - Adhesive forces are attractions between molecules in different substances.

• True

• False