Question

Read the text and choose from the sentences (A-F) the one that best fits each gap (1-5). There is one extra sentence. SELF - CLEANING FABRIC We've all, at some point, spilled something on our pristine clothes and then watched with dread as the stain spread. 1 For years, scientists have been trying to do just that, and it might surprise you to know that they may have finally succeeded! Researchers in Australia have coated cotton fabric with nanoparticles, , although invisible to the naked eye, have a very visible effect on fabric, as they are able to eliminate organic material. How does it work? Cbl After adding the nanoparticles to the fabric, it is immersed in a solution containing silver or copper molecules. These metals are both known for their ability to effectively absorb visible light, so they help the nanoparticles to absorb light also. 2 When this energy is released, it enables the nanoparticles to dissolve organic material, such as stains from perspiration, food or grass. Copper or silver? In their experiment, the researchers found differences in the performance of the nanoparticles. More specifically, the copper nanoparticles cleared a stain made from complex organic compounds in no time at all. 3 The silver nanoparticles, however, took 30 minutes to accomplish this task. Remarkably, both coatings also worked in low- light conditions, albeit at a slower rate. 4 The slower performance of silver doesn't mean that it was ineffective, though. In fact, after 15 exposures to organic compounds, the silver-coating consistently cleared close to 1006 of the compound, indicating that it may be more stable than copper, cleared less and less of the compound over time. What's next? Before clothes with this technology hit the market, many more studies need to be done. 5 These scientists also face the significant challenge of figuring out how to implement their invention on an industrial scale. Despite the long and difficult road ahead, these researchers are optimistic that their technology provides a solid foundation for the advancement of the textile industry. A When the particles are exposed to sunlight or artificial light bulb, there is an energy buildup in the form of hot electrons E3

A) When the particles are exposed to sunlight or artificial light bulb, there is an energy buildup in the form of hot electrons. B) Researchers have yet to examine how copper and silver nanoparticles perform on a wider range of stains. C) All the organic material had been eliminated within the span of three minutes. D)However, it isn't easy to permanently fix the nanoparticles to the fabric. E In those moments, you may have wondered why no one has invented a fabric that cleans itself. F) In the absence of bright light, the copper coating completed the cleaning task in 5 minutes, while the silver coating took 9 times longer. 1._ 2._ 3._4._5._​

Answer 1

ответ - - - - - - - - - - -) 1E 2a 3f 4c 5b