求英语大神帮忙翻译化学实验报告一篇.硫酸铝钾的制备及其晶体的培养一、实验目的1．了解从铝制备硫酸铝钾的原理及过程；2．进一步认识Al及Al(OH)3的两性；3．学习从溶液中培养晶体的原

求英语大神帮忙翻译化学实验报告一篇.硫酸铝钾的制备及其晶体的培养一、实验目的1．了解从铝制备硫酸铝钾的原理及过程；2．进一步认识Al及Al(OH)3的两性；3．学习从溶液中培养晶体的原
求英语大神帮忙翻译化学实验报告一篇.
硫酸铝钾的制备及其晶体的培养
一、实验目的
1．了解从铝制备硫酸铝钾的原理及过程；
2．进一步认识Al及Al(OH)3的两性；
3．学习从溶液中培养晶体的原理和方法.
二、实验原理
硫酸铝同碱金属的硫酸盐（K2SO4）作用生成硫酸铝钾复盐.
硫酸铝钾(K2SO4·Al2(SO4)3·24H2O)俗称明矾,它是一种无色晶体,易溶于水,并水解生成Al(OH)3胶状沉淀.它具有较强的吸附性能,是工业上重要的铝盐,可作为净水剂、造纸充填剂等多种用途.
本实验利用金属铝溶于氢氧化钠溶液,生成可溶性的四羟基铝酸钠,金属铝中其它的杂质则不溶,过滤除去杂质.随后用H2SO4调节此溶液的pH值为8－9,即有Al(OH)3沉淀产生,分离后,在沉淀中加入H2SO4,使Al(OH)3转化为Al2(SO4)3,然后制成Al2(SO4)3晶体,将Al2(SO4)3晶体和K2SO4晶体分别制成饱和溶液,混合后就有明矾生成.有关反应如下：
2Al + 2NaOH + 6H2O === 2Na[Al(OH) 4] + 3H2
[Al(OH)4 ]－+ H+ === Al(OH)3 + H2O
2Al(OH)3 + 3H2SO4 === Al2(SO4)3 + 6H2O
Al2(SO4)3 + K2SO4 + 24H2O === K2SO4·Al2(SO4)3·24H2O
明矾单晶的培养：当有K2SO4·Al2(SO4)3·24H2O晶体析出后,过滤得到晶体后,选出规整的作为晶种,放在滤液中,盖上表面皿,让溶液自然蒸发,结晶就会逐渐长大,成为大的单晶,单晶具有八面体晶形.为使晶种长成大的单晶,重要的是溶液温度不要变化太大,使溶液的水分缓慢蒸发.另外为长成大结晶,也可将生成的晶体系上尼龙绳,悬在溶液中.这样晶体在各方面生长速度不受影响,生成的晶体更规则.
三、实验用品
仪器与材料：烧杯,电子台秤,布氏漏斗,蒸发皿,酒精灯,三脚架,石棉网,火柴,玻璃漏斗,量筒,滤纸,pH试纸,尼龙线.
试剂： Al屑(C.P), NaOH(C.P) ,K2SO4(C.P), H2SO4(3mol·L－1,1:1),BaCl2（0.1 mol·L－1）.
四、实验步骤
1．Al(OH)3的生成
称取2.3克NaOH固体,置于200mL烧杯中,加入30mL蒸馏水溶解.称取1克铝屑,分批放入溶液中（反应剧烈,防止溅出,应在通风橱内进行）,至不再有气泡产生,说明反应完毕,然后再加入蒸馏水,使体积约为40mL,抽滤.将滤液转入200mL烧杯中,加热至沸,在不断搅拌下,滴加3mol·L－1H2SO4,使溶液的pH为8－9,继续搅拌煮沸数分钟,然后抽滤,并用沸水洗涤沉淀,直至洗涤液的pH值降至7左右,抽干.
2．Al2(SO4)3的制备
将制得的Al(OH)3转入烧杯中,在不断搅拌下,加入1:1 H2SO4,并水浴加热.当溶液变清后,停止加入硫酸,得Al2(SO4)3溶液.浓缩溶液为原体积的二分之一,取下,用水冷却至室温,待结晶完全后,抽滤,将晶体用滤纸吸干,称重.
3．明矾的制备及大晶体的培养
将称重的硫酸铝晶体置于小烧杯中,配成室温下的饱和溶液.另称取K2SO4固体,也配成同体积饱和溶液,然后将等体积的两饱和溶液相混合,搅拌均匀.放置后,就会有明矾晶体析出.过滤,选出规整的作为晶种,放在滤液中,盖上表面皿,让溶液自然蒸发,结晶就会逐渐长大,成为大的单晶,单晶具有八面体晶形.
为使晶种生成大的单晶,重要的是溶液温度不要变化太大,使溶液的水分缓慢蒸发.为生成大结晶,也可将生成的晶体系上尼龙绳,悬在溶液中.这样晶体在各方面生长速度不受影响.

求英语大神帮忙翻译化学实验报告一篇.硫酸铝钾的制备及其晶体的培养一、实验目的1．了解从铝制备硫酸铝钾的原理及过程；2．进一步认识Al及Al(OH)3的两性；3．学习从溶液中培养晶体的原
Cultivation and preparation of potassium aluminum sulfate crystals
First, the purpose of the experiment
1 . Learn from the principle of the preparation of aluminum and aluminum potassium sulfate process ;
2 . Further understanding of Al and Al (OH) 3 sexes ;
3 . Principles and methods of learning in the crystals from the solution.
Second, the experimental principle
Aluminum sulfate with an alkali metal sulfate (K2SO4) and potassium aluminum sulfate and generated salts.
Aluminum potassium sulfate (K2SO4 · Al2 (SO4) 3.24 H2O) , commonly known as alum, which is a colorless crystals , soluble in water and hydrolysis of Al (OH) 3 gel precipitation. It has strong adsorption properties is an important aluminum industry, can be used as purifying agent , paper filling agent for many purposes .
The experiment was dissolved in sodium hydroxide solution using the aluminum metal , aluminum hydroxy generated four soluble sodium aluminum impurities in the remaining insoluble impurities removed by filtration . H2SO4 followed by adjusting the pH of the solution was 8-9 , i.e. with Al (OH) 3 precipitate , after separation , the precipitate was added H2SO4 , that the conversion of 3 Al2 (SO4) 3 Al (OH), then formed Al2 (SO4) 3 crystals, Al2 (SO4) 3 K2SO4 crystals and crystals were saturated solution , after mixing, have generated alum . About the reaction is as follows :
2Al + 2NaOH + 6H2O === 2Na [Al (OH) 4] + 3H2
[Al (OH) 4] - + H + === Al (OH) 3 + H2O
2Al (OH) 3 + 3H2SO4 === Al2 (SO4) 3 + 6H2O
Al2 (SO4) 3 + K2SO4 + 24H2O === K2SO4 · Al2 (SO4) 3.24 H2O
Alum monocrystalline culture : When there K2SO4 · Al2 (SO4) 3.24 H2O after precipitation of crystals , the crystal was filtered , structured as a selected seed crystals in the filtrate, and covered with a watch glass , allowing the natural evaporation of the solution , crystallization will gradually grow to become a large single crystal , single crystals with octahedral crystal form . The seed crystal to be grown as a single crystal , it is important not to change the temperature of the solution is so large that the water solution was slowly evaporated. Also to be grown crystals can also be generated on the crystal system of nylon rope , suspended in solution. Such crystal growth rate is not affected in all respects , to generate a more regular crystals .
Third, experimental supplies
Instruments and Materials : beakers, electronic scales, Buchner funnel , evaporating dish , alcohol lamp , tripod, asbestos network , matches, glass funnel , graduated cylinder , filter paper , pH test strips, nylon cord.
Reagents : Al crumbs (CP), NaOH (CP), K2SO4 (CP), H2SO4 (3mol · L-1, 1:1), BaCl2 (0.1 mol · L-1).
Fourth, the experimental procedure
1 . Al (OH) 3 is generated
Weigh 2.3 g of solid NaOH , placed in 200mL beaker, add 30mL distilled water . Weigh 1 g of aluminum shavings in batches into the solution ( violent reaction against spills , should be carried out in a fume hood ) , to no more bubbles , and the reaction is completed, then add distilled water to bring the volume to approximately 40mL , filtration . The filtrate was transferred to 200mL beaker and heated to boiling , under continuous stirring , a solution of 3mol · L-1H2SO4, the pH of the solution is 8-9 , and stirring was continued for several minutes to boil , then suction filtered and the precipitate washed with boiling water until the pH value of the washing liquid is reduced to about 7 dry.
2 . Preparation of Al2 (SO4) 3 in
The resulting Al (OH) 3 into a beaker with constant stirring , was added 1:1 H2SO4, and water bath . When the solution becomes clear, stop the addition of sulfuric acid to give Al2 (SO4) 3 solution . The solution was concentrated to one half of the original volume , removed, cooled to room temperature and washed with water until crystallization was complete, filtered, the crystals were blotted dry with filter paper and weighed .
3 . Preparation and training of large crystals of alum
Aluminum sulfate crystals weighed into a small beaker, dubbed a saturated solution at room temperature. Another Weigh K2SO4 solid , also dubbed the same volume of a saturated solution , and then an equal volume of a saturated solution of the two -phase mixture, stirring well. After standing , alum crystals will be precipitated. Filtration , elected structured as a seed , on the filtrate , cover the surface of the pan, allow the solution to natural evaporation, crystallization will gradually grow to become a large single crystal , single crystals with octahedral crystal form .
In order to generate a large single crystal seed , it is important not to change the temperature of the solution is so large that the water solution was slowly evaporated. To generate large crystal , the crystal can also be generated on the system nylon rope suspended in the solution. Thus in all aspects of the crystal growth rate is not affected .