第2课时反应条件对化学平衡的影响

第2课时反应条件对化学平衡的影响 第2课时 反应条件对化学平衡的影响 1.概念 可逆反应由一个 变为另一个 的过程。 2(平衡移动方向的判断 如果平衡移动的结果使反应产物浓度更大，则称平衡 移动或 移动，反之，称平衡 移动或 移动。 3(化学平衡移动的原因及过程 (1)化学平衡移动的原因是反应条件的改变导致正、逆反应速率不相等，移动的结果是平衡混合 物中各组分的含量发生相应的变化。 (2)化学平衡移动的过程: 某条件下改变条件―――?不平衡――?新条件下平衡(?) 平衡，?， v,v v?v v′,v′ 正逆正逆正逆 Q,K Q?K Q,K 各组分含量 各组分含量 各组分含量 保持一定 发生变化 又保持一定 (下列说法不正确的是( ) 1( A(反应混合物各组分百分含量发生改变，化学平衡一定发生了移动 B(外界条件的改变引起浓度商或化学平衡常数改变，则平衡一定发生移动 C(平衡移动，反应物的浓度一定减小 D(外界条件发生变化，化学平衡不一定移动 (1)对反应2NO(g) NO(g) ΔH<0，升高温度，反应体系颜色 ，化学平衡向 方224 向移动。 反应方向移动;降低温度，平(2)结论:在其他条件不变的情况下，升高温度，平衡向 衡向 反应方向移动。 (3)原因:温度改变使 改变。 (4)温度改变时化学平衡移动的判断: 反应K值变Q与K平衡移动 温度变化 类型 化 关系 方向 放热 升温 Subsequently, the Anhui Army military Special Branch, in Shanghai's Central Intelligence Organization and the Communist party organization in Western Zhejiang Province, sent party backbone, respectively, went to Wu Jiangyan opened the Tomb, Tomb of heroic people, under the leadership of the Communist Party, fear no sacrifice and persevering, goal of the anti-Japanese revolutionary struggle. (A) stationed in Taoyuan area (Tomb of) 1, the new army of the Communist Party of China underground organization in September 1938, the CPC Zhuang Shaozhen (Zhuang Zhen, Nanxun people) by the Deputy Director of the political Department of the army on Deng Zihui's dispatch, operating from Jing County, Anhui Province, the Lake reached the Tomb, its tasks are: looking for reliable object, introduce them to the new, to expand the new team. Zhuang Shaozhen KMT-CPC cooperation as an opportunity, after classmates Yao Bi (Nanxun people, Ren Zhuxi force staff Director), introduced into the Kuomintang government political team, and as a political leader. He used this opportunity to invite progressive youth Hong Haiquan form a political team, at this point, the County Government has just been established, local school, unemployed youth are more quickly absorbed sheng, zhenze, Miaogang, Nanxun, huzhou, more than 20 more than required-Japanese youth. In order to raise the level of political players and the ability to work, Zhuang Shaozhen Xu Temple, is for the establishment of "youth ... Political activities will soon attract the attention of the Kuomintang. Is early Zhuang Shaozhen indicating Hong Haiquan to scoop the first elementary school, teacher's identity as a cover, carry out the party's work. However, County Director of education comes into action. To 反应 降温 吸热 升温 反应 降温 1,，在密闭容器中达到平衡，2(在某温度下，反应ClF(g)，F(g) ? ClF(g) ΔH,268 kJ?mol23 下列说法中正确的是( ) A(升高温度，K不变，平衡向正反应方向移动 B(温度升高，平衡常数变小 C(升高温度，平衡向正反应方向移动，F的转化率提高 2 D(降低温度，ClF的产率提高 3 1.影响 在其他条件不变的情况下，增大反应物浓度或减小生成物浓度，平衡 移动;减小反应物 浓度或增大生成物浓度，平衡 移动。 2(原因 浓度的改变导致 的改变，但K ，使Q K，从而导致平衡移动。但浓度的改变不一 定会使化学平衡发生移动 3.浓度对化学平衡的影响 平衡移 浓度变化 Q值变化 Q与K关系 动方向 反应物浓度增大 移动 生成物浓度减小 反应物浓度减小 移动 生成物浓度增大 4.特别提示 (1)化学平衡向右移动，生成物的产率一定增大，但生成物的浓度不一定增大，当减小生成物浓 度使化学平衡右移时，生成物的浓度减小。 (2)增加固态物质的用量，化学平衡不移动。 ,1,13(向盛有5 mL 0.005 mol?LFeCl溶液的试管中加入5 mL 0.01 mol?LKSCN溶液，充分混匀，3 溶液颜色深浅不再变化后建立化学平衡FeCl，3KSCN ? Fe(SCN)，3KCl。下列叙述中，不正确33(的是( ) A(加水至溶液的体积加倍，溶液血红色变浅，但化学平衡不移动 ,1B(再滴加少量0.1 mol?LKSCN溶液，溶液血红色变深，化学平衡右移 g Shaozhen indicating Hong Haiquan to scoop the first elementary school, teacher's identity as a cover, carry out the party'she establishment of "youth ... Political activities will soon attract the attention of the Kuomintang. Is early ZhuanJapanese youth. In order to raise the level of political players and the ability to work, Zhuang Shaozhen Xu Temple, is for t-than requiredmore n established, local school, unemployed youth are more quickly absorbed sheng, zhenze, Miaogang, Nanxun, huzhou, more than 20opportunity to invite progressive youth Hong Haiquan form a political team, at this point, the County Government has just beehe Kuomintang government political team, and as a political leader. He used this CPC cooperation as an opportunity, after classmates Yao Bi (Nanxun people, Ren Zhuxi force staff Director), introduced into t-new, to expand the new team. Zhuang Shaozhen KMT to theting from Jing County, Anhui Province, the Lake reached the Tomb, its tasks are: looking for reliable object, introduce them n (Zhuang Zhen, Nanxun people) by the Deputy Director of the political Department of the army on Deng Zihui's dispatch, operarground organization in September 1938, the CPC Zhuang ShaozheJapanese revolutionary struggle. (A) stationed in Taoyuan area (Tomb of) 1, the new army of the Communist Party of China unde-Communist Party, fear no sacrifice and persevering, goal of the antif the ovince, sent party backbone, respectively, went to Wu Jiangyan opened the Tomb, Tomb of heroic people, under the leadership oy Special Branch, in Shanghai's Central Intelligence Organization and the Communist party organization in Western Zhejiang PrSubsequently, the Anhui Army militarwork. However, County Director of education comes into action. To2 高二化学 化学反应的限度 编排:韩丽娟 审核:高二化学 时间:2014/10/8 ,1C(再滴加少量0.1 mol?LNaOH溶液，会有红褐色沉淀产生，上部溶液血红色变浅，化学平衡 左移 ,1D(再滴加少量0.1 mol?LFeCl溶液，溶液血红色变深，化学平衡右移 3 1(影响 在其他条件不变的情况下，增大压强，平衡向气态物质系数减小的方向移动;减小压强，平衡 向气态物质系数增大的方向移动。 2(原因 压强改变导致浓度改变，浓度的改变导致浓度商Q的改变，使Q?K，从而导致平衡移动。 3(压强对化学平衡的影响 方程式中气 平衡移动方态物质系数压强变化 Q值变化 Q与K关系 向 变化 增大 移动 ,0 Δνg减小 移动 增大 移动 Δν,0 g减小 移动 增大 Δν,0 移动 g减小 (1)对于只有固体或液体参加的反应，改变压强，平衡不移动。 (2)通常所指加压即是缩小容积，减压即是增大容积。 (3)勒?夏特列原理:在封闭体系中，如果改变影响平衡的一个条件(如浓度、温度或压强)，平衡 就向着能够减弱这种改变的方向移动。 (4)平衡移动的结果只能“减弱”而不能“消除”更不能“超越”这种改变。 4(压强变化不会使下列化学反应的平衡发生移动的是( ) A(H(g)，Br(g) ? 2HBr(g) 22 B(3H(g)，N(g) ? 2NH(g) 223 C(2SO(g)，O(g) ? 2SO(g) 223 D(C(s)，CO(g) ? 2CO(g) 2 [例1] 在一体积可变的密闭容器中，加入一定量的X、Y，发生反应mX(g) ? nY(g) ΔH, ty, backbone, respectively, went to Wu Jiangyan opened the Tomb, Tomb of heroic people, under the leadership of the Communist Par in Shanghai's Central Intelligence Organization and the Communist party organization in Western Zhejiang Province, sent party Subsequently, the Anhui Army military Special Branch,ounty Director of education comes into action. Toting Hong Haiquan to scoop the first elementary school, teacher's identity as a cover, carry out the party's work. However, Cindicaestablishment of "youth ... Political activities will soon attract the attention of the Kuomintang. Is early Zhuang Shaozhen anese youth. In order to raise the level of political players and the ability to work, Zhuang Shaozhen Xu Temple, is for the Jap-edcal school, unemployed youth are more quickly absorbed sheng, zhenze, Miaogang, Nanxun, huzhou, more than 20 more than requirvite progressive youth Hong Haiquan form a political team, at this point, the County Government has just been established, lohe Kuomintang government political team, and as a political leader. He used this opportunity to inCPC cooperation as an opportunity, after classmates Yao Bi (Nanxun people, Ren Zhuxi force staff Director), introduced into t-he new team. Zhuang Shaozhen KMTpand tunty, Anhui Province, the Lake reached the Tomb, its tasks are: looking for reliable object, introduce them to the new, to exanxun people) by the Deputy Director of the political Department of the army on Deng Zihui's dispatch, operating from Jing Corground organization in September 1938, the CPC Zhuang Shaozhen (Zhuang Zhen, NJapanese revolutionary struggle. (A) stationed in Taoyuan area (Tomb of) 1, the new army of the Communist Party of China unde-fear no sacrifice and persevering, goal of the anti3 ,1Q kJ?mol。反应达到平衡时，Y的物质的量浓度与温度、气体体积的关系如下表所示: 气体体积/L ,1 c (Y)/mol?L1 2 3 温度/? 100 1.00 0.75 0.53 200 1.20 0.90 0.63 300 1.30 1.00 0.70 下列说法正确的是( ) A(m>n B(Q<0 C(温度不变，压强增大，Y的质量分数减少 D(体积不变，温度升高，平衡向逆反应方向移动 (1)外界条件改变时，只有使v?v或Q?K时，才会发生化学平衡的移动。 正逆 (2)“惰性”气体对化学平衡的影响(“惰性”气体指不参与反应的气体)。 对于反应N(g)，3H(g) ? 2NH(g) ΔH<0来说: 223 ?若体系内的压强保持恒定(容器体积是可变的)时，加入氦气，体积必增大，使c(N)、c(H)、22 c(NH)变小，平衡向左移动(相当于减压)。 3 ?在恒温、恒容下，加入氦气时，平衡不发生移动，这种条件下加入“惰性”气体，虽平衡体 系内的压强增加，但因容器的体积不变，c(N)、c(H)、c(NH)不变，所以平衡不移动。 223 ?如果方程式中生成物和反应物的系数相等时，当惰性气体加入到已达平衡的体系中，不论什 么情况都不会使平衡移动。 ?催化剂会同等程度地改变v和v，但v和v仍然相等，平衡不移动。 正逆正逆 若将表格中“气体体积/L”改为 “气体压强/kPa”且“1”，“3” 位置互换，则结论有何变化, 2,2,[例2] (2011?安徽高考)电镀废液中CrO可通过下列反应转化成铬黄(PbCrO):CrO(aq)，274272，，2Pb(aq)，HO(l) 2PbCrO(s)，2H(aq) ΔH,0该反应达平衡后，改变横坐标表示的反应条件，24 opportunity to invite progressive youth Hong Haiquan form a political team, at this point, the County Government has just beehe Kuomintang government political team, and as a political leader. He used this CPC cooperation as an opportunity, after classmates Yao Bi (Nanxun people, Ren Zhuxi force staff Director), introduced into t-new, to expand the new team. Zhuang Shaozhen KMT to theting from Jing County, Anhui Province, the Lake reached the Tomb, its tasks are: looking for reliable object, introduce them n (Zhuang Zhen, Nanxun people) by the Deputy Director of the political Department of the army on Deng Zihui's dispatch, operarground organization in September 1938, the CPC Zhuang ShaozheJapanese revolutionary struggle. (A) stationed in Taoyuan area (Tomb of) 1, the new army of the Communist Party of China unde-Communist Party, fear no sacrifice and persevering, goal of the antif the ovince, sent party backbone, respectively, went to Wu Jiangyan opened the Tomb, Tomb of heroic people, under the leadership oy Special Branch, in Shanghai's Central Intelligence Organization and the Communist party organization in Western Zhejiang PrSubsequently, the Anhui Army militarwork. However, County Director of education comes into action. To g Shaozhen indicating Hong Haiquan to scoop the first elementary school, teacher's identity as a cover, carry out the party'she establishment of "youth ... Political activities will soon attract the attention of the Kuomintang. Is early ZhuanJapanese youth. In order to raise the level of political players and the ability to work, Zhuang Shaozhen Xu Temple, is for t-than requiredmore n established, local school, unemployed youth are more quickly absorbed sheng, zhenze, Miaogang, Nanxun, huzhou, more than 204 高二化学 化学反应的限度 编排:韩丽娟 审核:高二化学 时间:2014/10/8 下列示意图正确的是( ) 化学平衡图像问题的解答 方法 快递客服问题件处理详细方法山木方法pdf计算方法pdf华与华方法下载八字理论方法下载 1(解答步骤 ?看图像:一看面(即纵坐标与横坐标的意义)，二看线(即线的走向和变化趋势)，三看点(即起点，折点，交点，终点)，四看辅助线(如等温线、等压线、平衡线)，五看量的变化(如浓度变化、温度变化); ?想规律:联想外界条件的改变对化学反应速率和化学平衡的影响规律; ?作判断:根据图像中表现的关系与所学规律相对比，作出符合题目要求的判断。 2(解答原则 ?“定一议二”原则: 包括纵坐标、横坐标和曲线所表示的意义三个量，确定横坐标所表示的量在化学平衡图像中， 后，讨论纵坐标与曲线的关系或确定纵坐标所表示的量后，讨论横坐标与曲线的关系。 ?“先拐先平”原则: 在转化率(或含量等),时间曲线中，先出现拐点的曲线先达到平衡，它所代表的温度高、压强大。 ,1如图所示为可逆反应:mA(g)，nB(g) ? xC(g) ΔH,Q kJ?mol。在不同温度、压强下反应物A的转化率的变化情况如下图所示。下列对于反应的热效应Q和反应方程式A、B、C的系数的判断中，正确的是( ) A(Q>0，m，n>x B(Q>0，m，nx [随堂基础巩固] 1((2011?兰州诊断)已知:可逆反应2SO(g)，O(g) ? 2SO(g) ΔH<0，在一定条件下达到平223 衡后，改变下列条件一定能使该平衡向正反应方向移动的是( ) A(升温增压 B(降温增压 C(升温减压 D(降温减压 2(某温度下，密闭容器中发生反应aX(g) ? bY(g)，cZ(g)，达到平衡后，保持温度不变，将 vite progressive youth Hong Haiquan form a political team, at this point, the County Government has just been established, lohe Kuomintang government political team, and as a political leader. He used this opportunity to inCPC cooperation as an opportunity, after classmates Yao Bi (Nanxun people, Ren Zhuxi force staff Director), introduced into t-he new team. Zhuang Shaozhen KMTpand tunty, Anhui Province, the Lake reached the Tomb, its tasks are: looking for reliable object, introduce them to the new, to exanxun people) by the Deputy Director of the political Department of the army on Deng Zihui's dispatch, operating from Jing Corground organization in September 1938, the CPC Zhuang Shaozhen (Zhuang Zhen, NJapanese revolutionary struggle. (A) stationed in Taoyuan area (Tomb of) 1, the new army of the Communist Party of China unde-fear no sacrifice and persevering, goal of the antity, backbone, respectively, went to Wu Jiangyan opened the Tomb, Tomb of heroic people, under the leadership of the Communist Par in Shanghai's Central Intelligence Organization and the Communist party organization in Western Zhejiang Province, sent party Subsequently, the Anhui Army military Special Branch,ounty Director of education comes into action. Toting Hong Haiquan to scoop the first elementary school, teacher's identity as a cover, carry out the party's work. However, Cindicaestablishment of "youth ... Political activities will soon attract the attention of the Kuomintang. Is early Zhuang Shaozhen anese youth. In order to raise the level of political players and the ability to work, Zhuang Shaozhen Xu Temple, is for the Jap-edcal school, unemployed youth are more quickly absorbed sheng, zhenze, Miaogang, Nanxun, huzhou, more than 20 more than requir5 容器的容积压缩到原来容积的一半，当达到新平衡时，物质Y和Z的浓度均是原来的1.8倍。则下 列叙述正确的是( ) A(可逆反应的系数:a>b，c B(压缩容器的容积时，v(正),v(逆) C(达到新平衡时，物质X的转化率减小 D(达到新平衡时，混合物中Z的质量分数增大 3(反应NHHS(s) ? NH(g)，HS(g)在某温度下达到平衡，下列各种情况中，不会使平衡发432 生移动的是( ) A(温度、容积不变时，通入SO气体 2 B(移走一部分NHHS固体 4 C(容器体积不变，充入HCl气体 D(保持压强不变，充入氮气 4(在密闭容器中进行如下反应:X(g)，Y(g) ? 2Z(g)，在温度T和T时，产物的量与反应2212时间的关系如图所示。符合图示的正确判断是( ) A(TT，正反应是吸热反应 C(T>T，正反应是放热反应 D(T1212 5(在2 L密闭容器中，800 ?时反应2NO(g)，O(g) ? 2NO(g)体系中，n(NO)随时间的变化22如表: 时间(s) 0 1 2 3 4 5 n(NO)(mol) 0.020 0.010 0.008 0.007 0.007 0.007 (1)写出该反应的平衡常数表达式:K,________， 已知:K(300 ?),K(350 ?)，该反应是________反应(填“放热”或“吸热”); (2)如图中表示NO的变化的曲线是________。 2 (3)能说明该反应已经达到平衡状态的是( ) a(v(NO),2v(O) b(容器内压强保持不变 22 c(v(NO),2v(O) d(容器内的密度保持不变 逆正2 (4)可使平衡向正反应方向移动的是( ) a(及时分离出NO气体 b(适当升高温度 2 c(增大O的浓度 d(选择高效的催化剂 2 n established, local school, unemployed youth are more quickly absorbed sheng, zhenze, Miaogang, Nanxun, huzhou, more than 20opportunity to invite progressive youth Hong Haiquan form a political team, at this point, the County Government has just beehe Kuomintang government political team, and as a political leader. He used this CPC cooperation as an opportunity, after classmates Yao Bi (Nanxun people, Ren Zhuxi force staff Director), introduced into t-new, to expand the new team. Zhuang Shaozhen KMT to theting from Jing County, Anhui Province, the Lake reached the Tomb, its tasks are: looking for reliable object, introduce them n (Zhuang Zhen, Nanxun people) by the Deputy Director of the political Department of the army on Deng Zihui's dispatch, operarground organization in September 1938, the CPC Zhuang ShaozheJapanese revolutionary struggle. (A) stationed in Taoyuan area (Tomb of) 1, the new army of the Communist Party of China unde-Communist Party, fear no sacrifice and persevering, goal of the antif the ovince, sent party backbone, respectively, went to Wu Jiangyan opened the Tomb, Tomb of heroic people, under the leadership oy Special Branch, in Shanghai's Central Intelligence Organization and the Communist party organization in Western Zhejiang PrSubsequently, the Anhui Army militarwork. However, County Director of education comes into action. To g Shaozhen indicating Hong Haiquan to scoop the first elementary school, teacher's identity as a cover, carry out the party'she establishment of "youth ... Political activities will soon attract the attention of the Kuomintang. Is early ZhuanJapanese youth. In order to raise the level of political players and the ability to work, Zhuang Shaozhen Xu Temple, is for t-than requiredmore 6