Nanotechnology: Multiple Choice Grammar Test

Choose the correct item (A, B, C or D) to complete the sentences.

Nanotechnology deals (1) __________ materials on an extremely small scale. Nanomaterials can be particles, films, wires or even complete structures,(2) __________ balls and tubes. (3) __________ is key is their size. The prefix nano means a billionth. The largest objects (4) __________ by pioneering nanotechnologists are only 100 nanometers, or 100 billionths of a meter, across. Most are much (5) __________. Some are only (6) __________ atoms — a single nanometer — in diameter. For comparison, a human hair is about 20,000 nanometers (0.0008 inch) (7) __________.

And size is important. As materials shrink, their physical and chemical properties can change. For example, at the nanoscale gold isn’t yellow. Instead it (8) __________ red, green, blue or even purple, depending(9) __________ the size of the particles. This is due to effects that (10) __________ place on a quantum scale.