【单选题】
79.用磺基水杨酸分光光度法测铁时，将水样中的铁全部转化为( )，在pH＝9～11的条件下进行测定。
(A)Fe3＋; (B)Fe2＋; (C)Fe; (D)FeO。
A. Fe3+
B. Fe2+
C. Fe
D. FeO
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答案
A
解析
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【单选题】
80.摩尔法测定氯离子时，滴定过程中要剧烈摇动锥型瓶，其主要目的是( )。
(A)减少吸附；(B)加快反应速度；
(C)混合均匀；(D)提高滴定速度。
A. 减少吸附
B. 加快反应速度
C. 混合均匀
D. 提高滴定速度
【单选题】
81.用草酸钠标定高锰酸钾时，应控制滴定速度为( )。
(A)快-慢-快；(B)慢-快-慢；
(C)快-快-慢 (D)慢-快-快。
A. 快～慢～快
B. 慢～快～慢
C. 快～快～慢
D. 慢～快～快
【单选题】
82.热力设备的腐蚀与热负荷的关系是( )。
(A)无关； (B)随负荷增大，腐蚀加重；
(C)不确定； (D)随负荷增大，腐蚀减轻。
A. 无关
B. 随负荷增大，腐蚀加重
C. 不确定
D. 随负荷增大，腐蚀减轻
【单选题】
83.符合比耳定律的有色溶液稀释时，其波长及最大吸收峰值( )。
(A)不移动，降低； (B)不移动，增大；
(C)全部无变化； (D)向长波方向移动。
A. 不移动，降低
B. 不移动，增大
C. 全部无变化
D. 向长波方向移动
【单选题】
84.动态法钠度测定时最好使用内充( )mol/L KCl溶液的甘汞电极。
(A)0.1； (B)3.3； (C)1.0； (D)0.2。
A. 0.1
B. 3.3
C. 1.0
D. 0.2
【单选题】
85.从本质上来说，决定腐蚀速度的主要因素是( )。
(A)材料； (B)极化作用的大小；
(C)时间； (D)水中含氧量。
A. 材料
B. 极化作用的大小
C. 时间
D. 水中含氧量
【单选题】
86.用硼砂标定盐酸溶液时，称取一定量硼砂基准物，溶解后移至250mL容量瓶中，用移液管取25.00mL放入锥形瓶中，以待标的盐酸溶液滴定， 试问若滴定管没有用盐酸溶液冲洗，会使盐酸溶液浓度的标定结果( )。
A. 偏高
B. 偏低
C. 无影响
D. 无法确定
【单选题】
87.用硼砂标定盐酸溶液时，称取一定量硼砂基准物，溶解后移至250mL容量瓶中，用移液管取25.00mL放入锥形瓶中，以待标的盐酸溶液滴定， 试问若没有使用干燥的锥形瓶，内含少量蒸馏水，会使盐酸溶液浓度的标定结果( )。
A. 偏高
B. 偏低
C. 无影响
D. 无法确定
【单选题】
88.用硼砂标定盐酸溶液时，称取一定量硼砂基准物，溶解后移至250mL容量瓶中，用移液管取25.00mL放入锥形瓶中，以待标的盐酸溶液滴定之， 试问若滴定操作时，滴定管内的气泡没有被去除，会使盐酸溶液浓度的标定结果( )。
A. 偏高
B. 偏低
C. 无影响
D. 无法确定
【单选题】
89.用硼砂标定盐酸溶液时，称取一定量硼砂基准物，溶解后移至250mL容量瓶中，用移液管取25.00mL放入锥形瓶中，以待标的盐酸溶液滴定之， 试问若移液管没有用硼砂溶液冲洗，会使盐酸溶液浓度的标定结果( )。
A. 偏高
B. 偏低
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D. 无法确定
【单选题】
90.浓酸、浓碱一旦溅到眼睛或皮肤上，首先应采取( )的方法进行救护。
(A)稀HCl中和；(B)醋酸清洗；
(C)稀NaOH清洗；(D)清水冲洗。
A. 稀HCl中和
B. 醋酸清洗
C. 稀NaOH清洗
D. 清水冲洗
【单选题】
91.搬运和使用硫酸或强碱性药品的工作人员，应熟悉药品的( )。
(A)规格；(B)用途；(C)性质和操作方法；
(D)安全措施。
A. 规格
B. 用途
C. 性质和操作方法
D. 安全措施
【单选题】
92.受氯气中毒较重者应( )。
(A)口服复方樟脑酊； (B)胸部用冷湿敷法救护；
(C)吸氧气； (D)施行人工呼吸。
A. 口服复方樟脑酊
B. 胸部用冷湿敷法救护
C. 吸氧气
D. 实行人工呼吸
【单选题】
94.热力机械工作票中的工作许可人一般由( )担任。
(A)运行副主任；(B)运行专职工程师；
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B. 运行专职工程师
C. 运行正副班长或主值
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【单选题】
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(A)较多； (B)很小或没有；
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