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1.我国古代书法家、画家用墨(用炭黑等制成)书写或绘制的字画为什么能够保存很长时间而不变色?这是因为单质碳在常温下,化学性质不活泼。2.你知道为什么不粘锅不粘食物吗?这是因为锅底涂上了一层不粘涂层——聚四氟乙烯。这种材料具有耐高温、抗酸抗碱、抗各种有机溶剂的特点,几乎不溶于所有的溶剂。3.你知道黄金制品的纯度单位吗?黄金制品都是按国际标准提纯配制而成的,用K来表示金属制品中含金量的
1. Why can ancient Chinese calligraphers and painters use ink (made of carbon black etc.) to write or draw pictures for a long time without discoloration? This is because elemental carbon is chemically inactive at normal temperature. 2. Do you know why you do not stick non-stick food? This is because the bottom of the pot is coated with a non-stick coating - Teflon. This material has high temperature, acid and alkali resistance, a variety of organic solvents, almost insoluble in all solvents. Do you know the purity unit of gold products? Gold products are prepared by purification according to international standards, with K to represent the gold content of metal products