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英语翻译一、实验准备实验仪器、药品、材料:棉线,丝线200ML烧杯两个,硬纸片一张、滤纸若干、酒精灯一个、石棉网、带铁圈

来源:学生作业帮 编辑:作业帮 分类:英语作业 时间:2024/07/05 19:31:10
英语翻译
一、实验准备
实验仪器、药品、材料:棉线,丝线200ML烧杯两个,硬纸片一张、滤纸若干、酒精灯一个、石棉网、带铁圈的铁架台、温度计、硫酸铜粉末若干、玻璃棒.
二、实验步骤
1.在烧杯中放入100ML蒸馏水,加热到比室温高10~20℃,并加入足量硫酸铜;
2.用玻璃棒搅拌,直到饱和(有少量晶体不能再溶解),趁热过滤到一个已加热的烧杯中;
3.用硬纸片盖好,静置一夜,使其缓慢降温,析出晶体;
4.第二天杯底出现小晶体,每个约长0.5CM,取一个晶体较完整的,用丝线绑住,系在一根木棍上.高5~10℃,添加少量硫酸铜,使其再次饱和.
6.将已绑好的小硫酸铜晶体放入微热饱和硫酸铜溶液中,注意使其被完全浸没,且不能碰到杯壁或杯底.
7.用硬纸片盖好,静置过夜;每天观察,重复6、7项的操作过程.
四、实验结论
(1)硫酸铜的溶解度随着温度的升高而增大,通过严格控制温度的变化,有利于加快晶体的成形速率;
(2)模型必须悬挂在溶液中,若模型与杯壁贴合,冷却后溶液析出的晶体将附着在线圈和杯壁之间,成形的晶体形状不规则.
三、实验注意
1.控制溶液的温度,加热时要把晶体取出,等溶液温度均匀后再把晶体浸入。
2.注意环境温度的变化,应使饱和溶液缓慢冷却。
3.所用容器必须洁净,要加盖以防灰尘落入。
1.Experiment preparation
Laboratory equipment,pharmaceuticals,materials:cotton thread,silk thread,two 200ml beakers,a piece of cardboard,a number of filter papers,a kerosene lamp,asbestos net,iron stand with hoops,thermometer,copper sulfate powder,and a glass rod.
2.Experimental procedure
(1) Pour 100 ml of distilled water into abeaker and heat it to a temperature 10 to 20 ° C higher than room temperature,and add sufficient quantities of copper sulfate;
(2) Stir with a glass rod,until saturated(a small amount of crystal cannot be dissolved),filter the hot solution to a heated beaker;
(3 )Cover the beaker with a cardboard,and allowed to stand overnight to let it slowly cooling down and crystalized.
(4) The next day small crystals appear at the bottom of the beaker,each about 12.5px long,then take a relatively complete crystal,fasten to a wooden stick with a silk thread.
(5) Heat the solution to a temperature 5 to 10 ° C above room temperature,add a small amount of copper sulfate,and make it saturated again.
(6) Put the fastened copper sulfate crystal into warm saturated copper sulfate solution,note that it is completely submerged,and does not touch the wall or bottom of the beaker.
(7) Cover the beaker with a cardboard,and allowed to stand overnight; observed daily,and repeat the procedure of steps 6 and 7.
3.Experimental care
(1) Control the temperature of the solution,the crystal should be removed before heating the solution,the crystal is immersedin solution when temperature became uniform.
(2) Pay attention to the change of ambient temperature,the saturated solution should be cooled slowly.
(3) Containers used must be clean,and must be covered to prevent falling in dust.
4.Experimental conclusions
(1) The solubility of copper sulfate increases with the rising of temperature,crystal forming rate speeds up by strict control of temperature changes;
(2) The model must be suspended in the solution.If the model and the glass laminating,after cooling the solution,precipitated crystal will adhere between the coil and the glass,and the forming of the crystal shape will be irregular.
英语翻译一、实验准备实验仪器、药品、材料:棉线,丝线200ML烧杯两个,硬纸片一张、滤纸若干、酒精灯一个、石棉网、带铁圈 初二科学探究题设计实验需要的仪器:烧杯、玻璃棒、蒸发皿、酒精灯、漏斗、药匙、铁架台(带铁圈),滤纸___________ 某实验小组只领取下列仪器和用品:铁架台、铁夹、铁圈、三角架、石棉网、烧杯、漏斗、分液漏斗、酒精灯、玻璃棒、量筒、蒸发皿、 今有下列仪器:铁架台、铁圈、三脚架、烧杯、圆底烧瓶、漏斗、分液漏斗、滤纸、石棉网、酒精灯、玻璃棒、量筒、蒸发皿、冷凝管、 以酒精、水为原料,选用酒精灯、蒸发皿、带铁圈的铁架台、烧杯、玻璃棒、量筒、胶头滴管等仪器中的部分仪器,设计实验证明:(注 试用一只塑料可乐瓶,一张硬纸片一根吸管等材料设计几个有关于压强的实验.(至少设计两个). 以水、酒精为原料,以酒精灯、蒸发皿、带铁圈的铁架台、烧杯、玻璃棒、量筒等为仪器,设计实验证明分子是不断运动着的及分子间有 用一根拉紧的棉线或金属丝线连接两个小纸杯,这样就制成了一个“土电话机”,几个同学在一起用“土电话机”做实验, 烧杯、酒精灯、酒精灯三脚架、试管、石棉网、PH试纸之类的化学实验用具哪有卖的 设计物理实验如何用一个塑料可乐杯,一根吸管,一张硬纸片设计两个关于压强的试验 铁架台、酒精灯、玻璃棒、烧杯、试管是实验仪器吗 观察实验现象要借助实验仪器和药品,否则就观察不到相关的现象.(1)观察蜡烛燃烧的产物使用的仪器是烧杯.两个烧杯一个要求要