问题 填空题

卤素单质的性质活泼,卤素的化合物应用广泛,运用化学反应原理研究卤族元素的有关性质具有重要意义。

(1)下列关于氯水的叙述正确的是_______(填写序号)。

A.氯水中存在两种电离平衡                    

B.向氯水中通入SO2,其漂白性增强

C.向氯水中通入氯气,c( H)/c(ClO)减小       

D.加水稀释氯水,溶液中的所有离子浓度均减小

E.加水稀释氯水,水的电离平衡向正反应方向移动

F.向氯水中加少量固体NaOH,可能有c(Na)=c(Cl )+c(ClO)

(2)工业上通过氯碱工业生产氯气,其反应的离子方程式为______。

(3)常温下,已知25℃时有关弱酸的电离平衡常数:

写出84消毒液(主要成分为NaClO)露置在空气中发生反应的有关化学方程式________。若将84消毒液与洁厕剂(含有浓盐酸)混合使用可能会导致中毒,请用离子方程式解释有关原因___________。

(4)碘钨灯具有比白炽灯寿命长且环保节能的;特点。一定温度下,灯泡内封存的少量碘与使用过程中沉积在管壁上的钨可以发生反应: 。为模拟上述反应,准确称取0. 508g碘、0.736g金属钨置于50. 0mL的密闭容器中,加热使其反应。如图是 WI2(g)的物质的量随时间变化关系图象,其中曲线I(0~t2时间段)的反应温度为T1,曲线II(从t2开始)的反应温度为T2,且T2>T1。则

①该反应的△H_______0(填“>。、=或“<”)

②从反应开始到t1时间内的平均反应速率v(I2)=_________。

③下列说法中不正确的是_________(填序号),

A.利用该反应原理可以提纯钨

B.该反应的平衡常数表达式是K=

C.灯丝附近温度越高,灯丝附近区域WI2越易变为W而重新沉积到灯丝上

(5)25℃时,向5mL含有KCI和KI浓度均为0.1mol/L的混合液中,滴加6mL0.1mol/L的AgNO3溶液,先生成的沉淀是_________,溶液中离子浓度由大到小的顺序是_______ [不考虑H和OH。25℃时]。

答案

(1)A E F

(2)2Cl-+2H2O2OH-+Cl2↑+H2

(3)NaClO+CO2+ H2O=HClO+NaHCO3 ; 2HClO2HCl+O2↑。ClO-+Cl-+2H+= Cl2↑+H2O。

(4)① < ② 0.036/t1mol/(L·min) ③ B

(5)AgI  c(K+)> c(NO3-)> c(Cl-)> c(Ag+)> c(I-).

题目分析:(1)在氯水中存在两种弱电解质,H2O、HClO。它们都存在着电离平衡H2OH++OH-;HClOH++ClO-。正确。B. 向氯水中通入SO2,发生反应:Cl2+SO2+2H2O=H2SO4+2HCl,产生的H2SO4和HCl都没有漂白性。因此漂白作用减弱。C.向氯水中通入氯气,平衡:Cl2+H2O H++Cl-+HClO正向移动,c(H+) 增大,HClOH++ClO-逆向移动,c(ClO-) 减小,c( H)/c(ClO)增大。错误。D.加水稀释氯水,溶液中的H+、ClO-、Cl-离子浓度减小,但由于c(H+)·c(OH-)=Kw.所以c(OH-)增大。错误。E.加水稀释氯水,由于Cl2+H2O H++Cl-+HClO正向移动,酸电离产生的c(H+) 减小。对水的抑制作用减弱,所以水的电离平衡向正反应方向移动。正确。F.向氯水中加少量固体NaOH,发生反应Cl2+NaOH= NaCl+NaClO。若恰好完全反应则有c(Na)=c(Cl )+c(ClO)。正确。所以正确选项为A、E、F。(2)氯碱工业生产氯气,其反应的离子方程式为2Cl-+2H2O2OH-+ Cl2↑+H2↑.(3)由电离平衡常数H2CO3>HClO>HCO3-,可知:H2CO3>HClO,因此84消毒液露置在空气中发生反应的有关化学方程式NaClO+CO2+ H2O=HClO+NaHCO3。2HClO2HCl+O2↑若将84消毒液与洁厕剂(含有浓盐酸)混合使用可能会发生反应:ClO-+Cl-+2H+= Cl2↑+H2O产生有毒的气体Cl2导致中毒。(4)①因为升高温度,WI2的平衡含量降低,说明升高温度,化学平衡向逆反应方向移动。根据平衡移动原理,升高温度,化学平衡向吸热反应方向移动,逆反应方向为吸热反应,所以正反应为放热反应,因此ΔH <0. ②从反应开始到t1时间内的平均反应速率v(I2) =v(WI2)= Δc/Δt=1.80×10-3mol/0.05L÷t1min="0.036/t1mol/(L·min)" .③A. 使用不纯的的W与I2发生反应制取气体WI2,当反应达到平衡后升高温度,平衡逆向移动,就能产生纯净的单质W。因此可利用该反应原理可以提纯钨。正确。B. 由于W是固体,浓度不会改变,所以该反应的平衡常数表达式是。错误。C.灯丝附近温度越高,结构平衡移动原理可知:灯丝附近区域WI2就会逆向移动,产生更多的W而重新沉积到灯丝上。正确。(5)由于Ksp(AgI)< Ksp(AgI).所以首先产生的沉淀为AgI。在混合前n(K+)=(5mL+5mL)×10-3L/mL×0.1mol/L=0.001mol;n(Ag+)=n(NO3-)=0.006L×0.1mol/L=0.0006mol;n(Cl-)=n(I-)=0.005L×0.1mol/L=0.0005mol;在混合溶液中K+、NO3-不消耗,发生反应:Ag++I-=AgI↓;Ag++Cl-=AgCl↓.根据消耗的微粒的物质的量,可确定溶液中离子的浓度大小关系为:c(K+)> c(NO3-)> c(Cl-)> c(Ag+)> c(I-).

选择题
阅读理解

Going green seems to be fad(时尚)for a lot of people these days. Whether that is good or bad, we can’t really say, but for the tow of us, going green is not a fad but a lifestyle.

On April22, 2011, we decided to go green every single day for an entire year. This meant doing 365 different green things, and it also meant challenging ourselves to go green beyond easy things. Rather than recycle and reduce our energy, we had to think of 365 different green things to do and this was no easy task.

With the idea of going green every single day for a year, Our Green Year started. My wife and I decided to educate people about how they could go green in their lives and hoped we could show people all the green things that could be done to help the environment. We wanted to push the message that every little bit helps.

Over the course of Our Green Year, we completely changed our lifestyle. We now shop at organic(有机的)stores. We consume less meat, choosing green food. We have greatly reduced our buying we don’t need. We have given away half of what we owned through websites. Our home is kept clean by vinegar and lemon juice, with no chemical cleaners. We make our own butter, enjoying the smell of home-made fresh bread. In our home office anyone caught doing something ungreen might be punished.

Our minds have been changed by Our Green Year. We are grateful for the chance to have been able to go green and educate others. We believe that we do have the power to change things and help our planet.

小题1:What might be the best title for the passage?

A.Going Green.

B.Protecting the Planet.

C.Keeping Open-Minded

D.Celebrating Our Green Year.小题2:It was difficult for the couple to live a green life for the whole year because_________.

A.they were expected to follow the green fad

B.they didn’t know how to educate other people

C.they were unwilling to reduce their energy

D.they needed to perform unusual green tasks小题3:What did the couple do over the course of Our Green Year?

A.They tried to get out of their ungreen habits.

B.They ignore others’ ungreen behavior.

C.They chose better chemical cleaners.

D.They sold their home-made food.小题4:What can we infer form the last paragraph?

A.The government will give support to the green people.

B.The couple may continue their project in the future.

C.Some people disagree with the couple’s green ideas.

D.Our Green Year is becoming a national campaign.