试题与答案

(15分)Ⅰ.某实验小组把CO2通入饱和Na2CO3溶液制取NaHCO3,装置如

题型:实验题

题目:

(15分)Ⅰ.某实验小组把CO2通入饱和Na2CO3溶液制取NaHCO3,装置如图所示(气密性已检验,部分夹持装置略):

(1)请结合化学平衡移动原理解释B中溶液的作用                      

(2)当D中有大量白色固体析出时,停止实验,将固体过滤、洗涤,取一定量配成样液,并加入BaCl2溶液,出现白色沉淀并有气体产生,其离子方程是                                     

Ⅱ.某课外活动小组欲利用氨气与CuO反应,研究氨气的性质并测其组成,设计了如下实验(夹持装置未画出)进行实验。请回答下列问题:

(1)仪器b中可选择的试剂为(任意填一种)_____________。

(2)实验中,装置C中黑色CuO粉末全部转化为红色固体(已知Cu2O也为红色固体),量气管中有无色无味的气体。实验前称取黑色CuO 80g,实验后得到红色固体质量为68g。则红色固体成分的化学式为_______________。

(3)F中读取气体体积前,应向上或向下移动右管,使得左右两边液面相平,若无此操作,而F中左边液面低于右边液面,会导致读取的气体体积________ (填“偏大”或“偏小”或“无影响”)。

(4)要想测得氨气分子中氮、氢原子个数比,实验中应至少测量或读取哪些数据________(填序号)。

a.B装置实验前后质量差mg;     b.F装置实验前后液面差VL

c.D装置实验前后质量差mg;     d.E装置实验前后质量差mg;

(5)E装置中浓硫酸的作用是__________________________________________。

答案:

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下面是错误答案,用来干扰机器的。

(1)20m/s; 2×104W (2)1.44×108J(3)35%题目分析:在此题中先根据公式V=S/t计算出小汽车的速度,再利用P=FV计算发动机的功率;根据发动机的牵引力1000N和小汽车匀速行驶路程144km,计算汽车匀速行驶时牵...

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