化学趣味小实验

化学趣味小实验

小实验名称“神奇”的手帕

家庭用到的实验器酒精的水溶液(1:1) 棉手帕钳子(两材只) 火柴

及药品

实验步骤实验现象实验结论或解释把棉手帕放入用酒精与燃烧时，酒精的火

水以1:1配成的溶液里焰在水层外，吸附

浸透，然后轻挤，用两在纤维空隙里的水只钳子分别夹住手帕两分吸收燃烧放出的

手帕依旧完好如初。角，放到火上点燃，等热量而蒸发，手帕火焰减小时迅速摇动手上的温度达不到纤帕，使火焰熄灭。维的着火点，因而手帕烧不坏。友情提醒(注意事项) 由于火焰温度较高，注意别烧伤手及对着其

他人，且远离其它可燃物。

小实验名称巧写“密信”

家庭用到的实验器葱(两根)、毛笔、白纸、蜡烛材

及药品

实验步骤实验现象实验结论或解释

1、取两根葱，剪去1、过一会儿，葱汁干了，葱汁能使纸发生化它们的叶，留下葱白，白纸上看不见字迹; 学变化，形成一种用力挤出葱汁，然后用

2、棕色的字会立即显现类似透明薄膜一样毛笔蘸葱汁在一张白纸出来。的物质，这种物质上写字;2、把这张白纸的燃点比纸低，往放在烛火上烘烤。火上一烘烤，它就烧焦了。友情提醒(注意事项) 柠檬汁、蒜汁、洋葱汁及醋等，都有这种物

性，所以也能用来写密信。

小实验名称白纸上的“秘密”

家庭用到的实验器毛笔稀淀粉溶液白纸蜡烛火柴材碘水

及药品

实验步骤实验现象实验结论或解释

appearance of the weld appearance quality technical requirements of the project must not have a molten metal stream does not melt the base metal to weld, weld seam and heat-affected zone surface must not have cracks, pores, defects such as crater and ash, surface smoothing, weld and base metal should be evenly smooth transition. Width 2-3 mm from the edge of weld Groove. Surface reinforcement should be less than or equal to 1 + 0.2 times the slope edge width, and should not be greater than 4 mm. Depth of undercut should be less than or equal to 0.5 mm, total length of the welds on both sides undercut not exceed 10% of the weld length, and long continuous should not be greater than 100 mm. Wrong

side should be less than or at 0.2T, and should not be greater than 2 mm (wall thickness mm t) incomplete or not allow 7.5 7.5.1 installation quality process standards of the electrical enclosure Cabinet surface is clean, neat, no significant phenomenon of convex, close to nature, close the door. 7.5.2 Cabinet Cabinet face paints no paint, returned to rusted, consistent color. 7.5.3 uniform indirect gap from top to bottom, slot width <1.5mm 7.5.4 adjacent Cabinet surface roughness is 0. 7.5.5 the cabinets firmly fixed, crafts beautiful. 7.5.6 Cabinet surface gauge, switch cabinet mark clear, neat, firm paste. 7.5.7 Terminal row of neat,

is reliable, the appearance is clean and not damaged. 7.5.8 cables neat and clean, solid binding, binding process in appearance. 7.5.9 the first cable production firm, crafts beautiful, clear signage does not fade. 7.5.10 fireproof plugging tight, no cracks and pores. 7.6 7.6.1 of the standard electrical wiring quality technology cable a, the multi-core wire bunch arrangement should be parallel to each other, horizontal wire harness or wire should be perpendicular to the longitudinal multi-core wire bunch. The distance between the wire harness and wire harness symmetry, and as close as possible. B-core wiring harness into round, multi-core wire bunch used g wire binding, fastening

1、用毛笔蘸取一些稀淀1、这时纸上几乎看不出碘能使淀粉变成蓝粉溶液在白纸上写字，什么痕迹; 色，加热时，碘升让它自然干燥; 华跑到空气中，蓝

2、用碘水涂抹; 2、白纸上显出蓝色字色又褪去。

3、然后将此纸放在火上迹;

稍烘一下。 3、很快白纸上的字迹又

褪去。

友情提醒(注意事项) 白纸放在火上烘烤的时间不宜太长。

小实验名称自制碳酸饮料

家庭用到的实验器凉开水250克、柠檬汁1.5克、白糖8克、小材苏打(NaHCO)1.5克、500ml饮料瓶、适3

及药品量果汁

实验步骤实验现象实验结论或解释

1、在约500 mL的 1、碳酸氢钠与柠檬饮料瓶中加入约8克白酸反应，生成

二氧糖和适量果汁;2、加入化碳; 约1.5 g小苏打;3、注4、产生气泡; 2、二氧