1. The development of colloid chemistry has led to the widespread use of nanomaterials. The analysis and application of the process below does not make sense $\_\_\_\_$ $\mathrm { Fe } \xrightarrow [ \text { I } ] { \mathrm { Cl } _ { 2 } } \mathrm { FeCl } \xrightarrow [ \text { II } ] { \text { 试剂(1)} } \mathrm { Fe } ( \mathrm { OH } ) _ { 3 }$ colloid

• A. A. Iron can react with $\mathrm { Cl } _ { 2 }$ and liquid chlorine cannot be stored in dry cylinders.
• B. B. Reagent (1) is boiling water, which produces a reddish-brown liquid
• C. C. Iron hydroxide colloids with dispersant particle diameters in the $1 \sim 100 \mathrm {~nm}$ range
• D. D. The properties of a material can be changed by changing its particle size.

Answer: A

2. Cobalt and its compounds have a wide range of applications in industry, electronics and other fields. A partial process for extracting cobalt from zinc smelting waste residue (mainly containing + 2-valent oxides or monomers of cobalt, zinc, lead, iron and manganese) is as follows:  It is known that: $\mathrm { K } _ { \mathrm { sp } } \left[ \mathrm { Fe } ( \mathrm { OH } ) _ { 3 } \right] = 1.0 \times 10 ^ { - 39 } , \mathrm {~K} _ { \mathrm { sp } } \left[ \mathrm { Co } ( \mathrm { OH } ) _ { 3 } \right] = 1.0 \times 10 ^ { - 44 } , \mathrm { Zn } ( \mathrm { OH } ) _ { 2 }$ and $\mathrm { Al } ( \mathrm { OH } ) _ { 3 \text { 的化 } }$ have similar chemical properties. The following statements are correct $$ \mathrm { ClO } ^ { - } + 2 \mathrm { Co } ^ { 2 + } + \mathrm { H } _ { 2 } \mathrm { O } + 4 \mathrm { OH } ^ { - } = \mathrm { Cl } ^ { - } + 2 \mathrm { Co } ( \mathrm { OH } ) _ { 3 } \downarrow $$

• A. A. It is known that the $\mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 8 }$ has ${ } ^ { S }$ elements with ${ } ^ { + 6 } , 1 \mathrm { molNa } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 8 }$ containing ${ } ^ { 2 \mathrm {~N} _ { \mathrm { A } } }$ peroxide bonds
• B. B. Combined with process analysis, $\mathrm { Fe } ^ { 2 + }$ is more reductive than $\mathrm { Co } ^ { 2 + }$
• C. C. Use FeS to remove $\mathrm { Zn } ^ { 2 + } , \mathrm { pH }$ from the filtrate. The larger the $\mathrm { Zn } ^ { 2 + }$ is, the better it is for removing $\mathrm { Zn } ^ { 2 + }$ from the filtrate.
• D. D. Ionic equation for "oxidized cobalt

Answer: B

3. Sodium borohydride is a white powder, commonly used as a reducing agent in organic synthesis, and decomposes in moist air. Sodium metaborate ( $\mathrm { NaBO } _ { 2 }$ ${ } ^ { 2 }$) is soluble in water, insoluble in ethanol, easily hydrolyzed, but stable under alkaline conditions. The procedure for making $\mathrm { NaBH } _ { 4 }$ from boron concentrate (which contains a certain amount of $\mathrm { B } _ { 2 } \mathrm { O } _ { 3 }$, and impurities such as $\mathrm { Al } _ { 2 } \mathrm { O } _ { 3 } , \mathrm { SiO } _ { 2 } , \mathrm { Fe } _ { 2 } \mathrm { O } _ { 3 }$), and analyzing the purity of $\mathrm { NaBH } _ { 4 }$ samples (the impurities do not take part in the reaction) is as follows.  Step I : Take $\mathrm { mg } _ { \text {样品配成 } } 250 \mathrm {~mL} _ { \text {溶液 } }$, take ${ } ^ { 25.00 m L }$ in an iodine measuring flask, and add $\mathrm { V } _ { 1 } \mathrm { ml } \mathrm { c } _ { 1 } \mathrm {~mol} \cdot \mathrm {~L}$ of $\mathrm { KIO } _ { 3 \text { 溶液,发生反应:} } \mathrm { NaBH } _ { 4 } + \mathrm { KIO } _ { 3 } \rightarrow \mathrm { NaBO } _ { 2 } + \mathrm { KI } + \mathrm { H } _ { 2 } \mathrm { O }$ (the chemical equation is not leveled). Step II: Add excess ${ } ^ { \mathrm { KI } }$ solution to the solution after the reaction in Step I, adjust ${ } ^ { \mathrm { pH } }$ to convert $\mathrm { KIO } _ { 3 }$ to ${ } ^ { \mathrm { I } _ { 2 } }$, cool, and leave it in the dark for a few minutes. Step III: Adjust ${ } ^ { \mathrm { pH } }$ of the mixture obtained in Step II to weak acidity, add a few drops of starch solution, titrate with ${ } ^ { \mathrm { C } _ { 2 } \mathrm {~mol} \cdot \mathrm {~L} ^ { - 1 } \mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 3 } }$ standard solution to the end point, a reaction occurs: $\mathrm { I } _ { 2 } + 2 \mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 3 } = 2 \mathrm { NaI } + \mathrm { Na } _ { 2 } \mathrm {~S} _ { 4 } \mathrm { O } _ { 6 }$, consuming $\mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 3 }$ standard solution $\mathrm { I } _ { 2 } + 2 \mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 3 } = 2 \mathrm { NaI } + \mathrm { Na } _ { 2 } \mathrm {~S} _ { 4 } \mathrm { O } _ { 6 }$. _17]] of standard solution $\mathrm { V } _ { 2 } \mathrm {~mL}$. The following operations related to this experiment are correct ( )

• A. A. The reagent used to adjust the pH in "Step II" can be a suitable amount of KOH solution.
• B. B. Inadvertent adjustment of the mixture to strong acidity during "Step III" will result in a high purity of the measured sample.
• C. C. When the last half drop of $\mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 3 }$ standard solution is added and the blue color of the solution disappears, the end point of the titration is reached.
• D. D. When reading, looking flat before titration and looking down after titration will result in a large purity of the measured sample

Answer: D

4. Known: (1) green tea contains a large amount of ellagic acid; (2) ferrous ellagic acid solution is colorless, ferric ellagic acid solution is blue-black, according to the analysis of the experimental process shown in the figure, the following narrative is incorrect () green tea leaves in water $- \underset { \text {(1)} } { - \underset { \text { add } } { \mathrm { FeSO } _ { 4 } } } \rightarrow \underset { \text { 蓝黑色 } } { - \underset { \text {(2)} } { \text { 维生入素 } } \underset { \text { 加 } } { \mathrm { C } } } \longrightarrow \underset { \text { 复为原色 } } { - \underset { \text {(3)} } { \text { drop in } } } \rightarrow \underset { \text { 不变色 } } { \text { KSCN solution } } - \underset { \text {(4)drop in } } { \mathrm { H } _ { 2 } \mathrm { O } _ { 2 } }$ solution $\rightarrow$ turned red

• A. A. The ferrous ellagic acid produced by the reaction of green tea leaf water with ${ } ^ { \mathrm { FeSO } _ { 4 } }$ is easily oxidized to ferric ellagic acid, which is blue-black in color.
• B. B. Vitamin C reduces ferric ellagic acid to ferrous ellagic acid
• C. C. ${ } ^ { \mathrm { H } _ { 2 } \mathrm { O } _ { 2 } }$ oxidizes $\mathrm { Fe } ^ { 2 + }$ to $\mathrm { Fe } ^ { 3 + }$ in (4).
• D. D. When taking iron supplements, it's best to drink some green tea water

Answer: D

5. A qualitative test of some ions in a sodium salt solution is performed as follows. The following analysis is correct  Known: ${ } ^ { - }$ in solution reacts with $\mathrm { Cu } ^ { 2 + }$ to form ${ } ^ { \mathrm { I } _ { 2 } }$ and $\mathrm { CuI } ^ { - }$ white precipitates.

• A. A. Step (2) operation is filtration and step (3) operation is distillation
• B. B. The ionic equation for the reaction of solution Y with hydrogen peroxide is $\mathrm { H } _ { 2 } \mathrm { O } _ { 2 } + 2 \mathrm { I } ^ { - } = \mathrm { I } _ { 2 } + 2 \mathrm { OH }$
• C. C. To test for the presence of $\mathrm { I } ^ { - }$ in this sodium salt solution, add silver nitrate solution acidified with nitric acid directly to the sodium salt solution
• D. D. The anions in this sodium salt solution react with $\mathrm { Cu } ^ { 2 + }$ in both complex decomposition and redox reactions

Answer: D

6. It is known that: (1) green tea contains a large amount of ellagic acid; (2) ferrous ellagic acid solution is colorless, ferric ellagic acid solution is blue-black. According to the analysis of the experimental process shown in the figure, the following narrative is wrong Green tea leaves water $\underset { \text {(1)} \text { add } } { \mathrm { FeSO } _ { 4 } }$ blue-black $\underset { \text {(2)add } } { \text { 维生素 } \mathrm { C } }$ return to the original color $\underset { \text {(3)drop in } } { \mathrm { KSCN } _ { \text {溶液 } } }$ does not change color $\underset { \text {(4)drop in } } { \mathrm { H } _ { 2 } \mathrm { O } _ { 2 } \text { 溶液 } }$ change to red

• A. A. The ferrous ellagic acid produced by the reaction of green tea leaf water with $\mathrm { FeSO } _ { 4 }$ is easily oxidized to ferric ellagic acid, which is blue-black in color.
• B. B. Vitamin C reduces ferric ellagic acid to ferrous ellagic acid
• C. C. (2 reactions occur in (4)
• D. D. You should not drink green tea when taking iron supplements

Answer: C

7. The main process of preparing anhydrous $\mathrm { NaHSO } _ { 3 }$ from ${ } ^ { \mathrm { SO } _ { 2 } }$ and soda ash as raw materials in industry is shown in the figure. The following analysis is correct ( ) 

• A. A. Masterbatch of $\mathrm { pH } > 7$
• B. B. The neutralized solution has more than two solutes in it
• C. C. Only glass rods and funnels are needed to simulate the separation of wet materials and mother liquors in the laboratory.
• D. D. Magnetite is produced when $\mathrm { SO } _ { 2 }$ is industrially prepared by reacting pyrite with oxygen at high temperatures

Answer: B

9. Ethylene oxide (b, molecular formula for $\mathrm { C } _ { 2 } \mathrm { H } _ { 4 } \mathrm { O }$, relative molecular mass of 44) is a colorless liquid at room temperature, is an important industrial synthesis intermediates and disinfectants. Analyzing the flow shown in the figure, the following statement is not correct ( ) 

• A. A. b, c are both more soluble in water
• B. B. $a$, $b$ Molecule with all atoms coplanar
• C. C. b and c both denature proteins
• D. D. a The addition products of $\mathrm { H } _ { 2 } \mathrm { O }$ and c are alcohols.

Answer: B

10. The laboratory process for simulating the removal of ammonia nitrogen ($\mathrm { NH } _ { 3 }$) from wastewater by an industrial bleach solution (with NaClO as the active ingredient) is as follows:  The following analysis is correct

• A. A. (Refining of crude brine by distillation in (1)
• B. B. (The main electrode reaction at the anode in (2): $4 \mathrm { OH } ^ { - } - 4 \mathrm { e } ^ { - } = 2 \mathrm { H } _ { 2 } \mathrm { O } + \mathrm { O } _ { 2 } \uparrow$
• C. C. (Reaction to prepare bleach solution in (3): $\mathrm { Cl } _ { 2 } + \mathrm { OH } ^ { - } = \mathrm { Cl } ^ { - } + \mathrm { HClO }$
• D. D. (Redox reactions occur in (2), (3) and (4)

Answer: D

11. It is known that: (1) green tea contains a large amount of ellagic acid; (2) ferrous ellagic acid solution is colorless, ferric ellagic acid solution is blue-black. According to the analysis of the experimental process shown in the figure, the following description is wrong ( ) $\underset { \text { 叶水 } } { \text { 绿茶 } } \underset { ( 1 ) \text { add } } { \mathrm { FeSO } _ { 4 } } \underset { \text { 蓝黑色 } } { \text { 维生素 } } \underset { \text {(2)add } } { \text { 恢复为 } } \underset { \text { 原色 } } { \mathrm { KSCN } \text { 溶液 } } \underset { \text {(3)drop in } } { \text { 不变色 } } \xrightarrow [ \text {(4)drop in } ] { \mathrm { H } _ { 2 } \mathrm { O } _ { 2 } \text { 溶液 } } \underset { \text { 红色 } } { \text { 变为 } }$

• A. A. The ferrous tannate produced by the reaction between green tea leaf water and ferrous sulfate is easily oxidized to ferric tannate and becomes blue-black in color.
• B. B. Vitamin C in reaction (2) exhibits oxidizing properties
• C. C. In reaction (4) $\mathrm { H } _ { 2 } \mathrm { O } _ { 2 }$ can be replaced with freshly made chlorine water.
• D. D. Green tea leaf water should not be taken at the same time as iron supplements

Answer: B

12. It is known that: (1) green tea contains a large amount of ellagic acid; (2) ferrous ellagic acid solution is colorless, ferric ellagic acid solution is blue-black, according to the analysis of the experimental process as shown in the figure, the following description is not correct $\underset { \text { 叶水 } } { \text { 绿茶 } } \underset { \text {(1)add } } { \mathrm { FeSO } _ { 4 } } \xrightarrow [ \text { 蓝黑色 } ] { \text { Vitamin C } } \xrightarrow [ \text {(2)add } ] { \text { 恢复为 } } \xrightarrow [ \text {(3)drop in } ] { \mathrm { KSCN } \text { 溶液 } }$ does not change color $\xrightarrow [ \text {(4)drop in } ] { \mathrm { H } _ { 2 } \mathrm { O } _ { 2 } \text { 溶液 } }$ becomes

• A. A. The ferrous ellagic acid produced by the reaction of green tea leaf water with ${ } ^ { \mathrm { FeSO } _ { 4 } }$ is easily oxidized to ferric ellagic acid, which is blue-black in color.
• B. B. Vitamin C reduces iron ellagic acid to ferrous ellagic acid
• C. C. $\mathrm { H } _ { 2 } \mathrm { O } _ { 2 }$ oxidizes $\mathrm { Fe } ^ { 2 + }$ to $\mathrm { Fe } ^ { 3 + }$ in (4).
• D. D. When taking iron supplements, it's best to drink some green tea water

Answer: D

13. Known: (1) green tea contains a large amount of ellagic acid; (2) ferrous ellagic acid solution is colorless, ferric ellagic acid solution is blue-black, generalized as shown in the figure of the experimental process analysis, the following description is wrong $\underset { \text { 叶水 } } { \text { 绿茶 } } \underset { \text {(1)add } } { \mathrm { FeSO } _ { 4 } } \underset { \text { 蓝黑色 } } { \mathrm { FeSO } _ { \text {(2)add } } ^ { \text {维生素 } } \mathrm { C } }$ is restored to $\underset { \text {(3)drop in } } { \mathrm { KSCN } \text { 溶液 } }$ does not change color $\xrightarrow [ \text {(4)drop in } ] { \mathrm { H } _ { 2 } \mathrm { O } _ { 2 } \text { 溶液 } } \underset { \text { 红色 } } { \text { 变为 } }$

• A. A. The ferrous ellagic acid produced by the reaction of green tea leaf water with $\mathrm { FeSO } _ { 4 }$ is easily oxidized to ferric ellagic acid, which is blue-black in color.
• B. B. Vitamin C reduces ferric ellagic acid to ferrous ellagic acid
• C. C. (Only 1 reaction occurs in (4)
• D. D. You should not drink green tea when taking iron supplements

Answer: C

16. Liquid $\mathrm { N } _ { 2 } \mathrm { O } _ { 4 }$ is an effective oxidizer for rocket propulsion systems. A small amount of $\mathrm { N } _ { 2 } \mathrm { O } _ { 4 }$ is prepared in the laboratory as follows, and the following analysis is incorrect ( ) $\mathrm { NH } _ { 4 } \mathrm { Cl }$ solid ${ } ^ { - - } \stackrel { \mathrm { Ca } ( \mathrm { O } ) _ { 2 } \text { 固体 } } { ( 1 ) } - \rightarrow \mathrm { NH } _ { 3 } \xrightarrow { - \frac { \text { 催化氦化 } } { ( 2 ) } } \mathrm { NO } ^ { - - } \xrightarrow { - \frac { \mathrm { O } } { ( 3 ) } } \rightarrow \mathrm { NO } _ { 2 } ( \text { 红棕色 } ) ^ { - - \frac { \text { 降温 } } { ( 4 ) } } \rightarrow \rightarrow \mathrm { N } _ { 2 } \mathrm { O } _ { 4 }$ liquid (colorless) 

• A. A. The valence of nitrogen changes in reactions (2) and (3)
• B. B. Reaction (2) utilizes the reducing properties of $\mathrm { NH } _ { 3 }$
• C. C. The color change in reaction (4) is caused by a shift in chemical equilibrium
• D. D. Reaction (1) can be realized by the device shown in the figure

Answer: D

17. Sodium borohydride is a white powder, commonly used as a reducing agent in organic synthesis, and decomposes in moist air. Sodium metaborate ( $\mathrm { NaBO } _ { 2 }$) is soluble in water, insoluble in ethanol, easily hydrolyzed, but can be stabilized under alkaline conditions. The procedure for making $\mathrm { NaBH } _ { 4 }$ from boron concentrate (which contains a certain amount of $\mathrm { B } _ { 2 } \mathrm { O } _ { 3 }$, and impurities such as $\mathrm { Al } _ { 2 } \mathrm { O } _ { 3 } , \mathrm { SiO } _ { 2 } , \mathrm { Fe } _ { 2 } \mathrm { O } _ { 3 }$), and analyzing the purity of a sample of $\mathrm { NaBH } _ { 4 }$ (with the impurity not taking part in the reaction) is as follows.  Step I : Take $\mathrm { mg } _ { \text {样品配成 } } 250 \mathrm {~mL} _ { \text {溶液 } }$, take ${ } ^ { 25.00 m L }$ in an iodine measuring flask, add $\mathrm { V } _ { 1 } \mathrm { ml } \mathrm { c } _ { 1 } \mathrm {~mol} \cdot \mathrm {~L}$ of $\mathrm { V } _ { 1 } \mathrm { ml } \mathrm { c } _ { 1 } \mathrm {~mol} \cdot \mathrm {~L}$ to it. $\mathrm { KIO } _ { 3 \text { 溶液,发生反应:} } \mathrm { NaBH } _ { 4 } + \mathrm { KIO } _ { 3 } \rightarrow \mathrm { NaBO } _ { 2 } + \mathrm { KI } + \mathrm { H } _ { 2 } \mathrm { O }$ (the chemical equation is not leveled). Step II: Add excess ${ } ^ { K I }$ solution to the solution from the reaction in Step I. Adjust ${ } ^ { p H }$ so that $\mathrm { KIO } ^ { 3 }$ is converted to $\mathrm { I } _ { 2 }$, cool it down, and then leave it in the dark for several minutes. Step III: Adjust ${ } ^ { \mathrm { pH } }$ of the mixture obtained in Step II to weak acidity, add a few drops of starch solution, titrate with ${ } ^ { \mathrm { C } _ { 2 } \mathrm {~mol} \cdot \mathrm {~L} ^ { - 1 } \mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 3 } }$ standard solution to the end point, a reaction occurs: $\mathrm { I } _ { 2 } + 2 \mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 3 } = 2 \mathrm { NaI } + \mathrm { Na } _ { 2 } \mathrm {~S} _ { 4 } \mathrm { O } _ { 6 }$, the consumption of of standard solution $\mathrm { V } _ { 2 } \mathrm {~mL}$. The following statement is correct ( )

• A. A. The main constituents of the filtrate are $\mathrm { Fe } ( \mathrm { OH } ) _ { 3 }$
• B. B. The main reason for adding CaO without $\mathrm { CaCl } _ { 2 }$ in the "silica-aluminum removal" step is to minimize the introduction of impurity ions and to create an alkaline environment that prevents hydrolysis of $\mathrm { NaBO } _ { 2 }$.
• C. C. "Operation 2" is the evaporation, crystallization and washing of the filtrate, where the reagent of choice for washing is preferably ice water.
• D. D. At the end of "operation 2" $\mathrm { NaBH } _ { 4 }$ can also be prepared by electrolysis if corrosion-resistant electrode materials are used, and the process produces ${ } ^ { 1 \mathrm {~mol} \mathrm { NaBH } } 4$ at the cathode for every ${ } ^ { 8 \mathrm {~mol} }$ electron transferred.

Answer: B

18. Waste cans (containing Al and small amounts of $\mathrm { Fe } , \mathrm { Mg }$ impurities) to prepare alum, analyze the process, the correct ( ) 

• A. A. To minimize the introduction of impurities, the NaOH solution should be replaced with KOH or ammonia.
• B. B. "Sedimentation" as $\mathrm { Al } _ { 2 } \left( \mathrm { CO } _ { 3 } \right) _ { 3 }$
• C. C. The above process can use excess $\mathrm { CO } _ { 2 }$ instead of $\mathrm { NH } _ { 4 } \mathrm { HCO } _ { 3 }$.
• D. D. The main components of the filter residue are $\mathrm { Fe } ( \mathrm { OH } ) _ { 3 }$ and $\mathrm { Mg } ( \mathrm { OH } ) _ { 2 }$

Answer: C

19. laboratory to investigate the preparation of potassium permanganate greening program, the experimental process is shown in the figure:  It is known that $\mathrm { K } _ { 2 } \mathrm { MnO } _ { 4 }$ under acidic, neutral and weakly basic environments, $\mathrm { MnO } _ { 4 } ^ { 2 - }$ undergoes its own redox (disproportionation) reaction to form $\mathrm { MnO } _ { 4 } ^ { - }$ and $\mathrm { MnO } _ { 2 }$. The following statement is incorrect ( )

• A. A. The "eutectic" feeding sequence is: KOH is added first, then $\mathrm { MnO } _ { 2 }$ and $\mathrm { KClO } _ { 3 }$ are added after melting.
• B. B. The $\mathrm { CH } _ { 3 } \mathrm { COOH }$ added during "disproportionation" provides an acidic environment while being oxidized to $\mathrm { CO } _ { 2 }$.
• C. C. The ratio of the amount of the oxidized product to the amount of the reduced product from the "disproportionation" step is $2 : 1$
• D. D. From the point of view of improving the utilization of raw materials, the advantage of this experimental process is that the filter residue can be recycled

Answer: B

20. Liquid $\mathrm { N } _ { 2 } \mathrm { O } _ { 4 }$ is an effective oxidizer for rocket propulsion systems. A small amount of $\mathrm { N } _ { 2 } \mathrm { O } _ { 4 }$ is prepared in the laboratory as follows. The following analysis is incorrect ( ) $\underset { \text { 固体 } } { \mathrm { NH } _ { 4 } \mathrm { Cl } } \xrightarrow [ \text {(1)} ] { \mathrm { Ca } ( \mathrm { OH } ) _ { 2 } \text { 固体 } } \mathrm { NH } _ { 3 } \xrightarrow [ \text {(2)} ] { \text { 催化氧化 } } \mathrm { NO } \xrightarrow [ \text {(3)} ] { \mathrm { O } _ { 2 } } \underset { \text {(红棕色)} } { \mathrm { NO } _ { 2 } } \xrightarrow [ \text {(4)} ] { \text { 降温 } } \underset { \text {(无色)} } { \mathrm { N } _ { 2 } \mathrm { O } _ { 4 } \text { 液体 } }$ 

• A. A. The valence of nitrogen changes in reactions (2) and (3)
• B. B. Reaction (2) utilizes the reducing properties of $\mathrm { NH } _ { 3 }$
• C. C. The color change in reaction (4) is caused by a shift in chemical equilibrium
• D. D. Reaction (1) can be realized by the device shown in the figure

Answer: D

21. One of the methods of industrial mercury production is cinnabar (containing mainly HgS) roasting, and the main reaction that occurs when cinnabar is roasted is The main reaction that occurs when cinnabar is roasted is $\mathrm { HgS } + \mathrm { O } _ { 2 } \xlongequal { \text { 焙烧 } } \mathrm { Hg } + \mathrm { SO } _ { 2 }$, which produces gaseous mercury, which is condensed to obtain liquid mercury. A process for preparing pure mercury from cinnabar is shown in the figure. The following analysis is correct ( ) 

• A. A. The main purpose of adding CaO during roasting is to lower the melting point of HgS
• B. B. Mercury-containing flue gas requires mercury removal before it can be released to the atmosphere
• C. C. Physical changes occur when washing with nitric acid in $5 \%$.
• D. D. Distillation in the laboratory requires apparatus such as distillation flasks, condenser tubes and dispensing funnels

Answer: B

22. The figure below shows the process of laboratory purification of potassium chloride containing a small amount of barium chloride impurity. The following analysis is incorrect () 

• A. A. Operation I is filtration to remove the solids.
• B. B. Reagent X is $\mathrm { K } _ { 2 } \mathrm { CO } _ { 3 }$ solution and operation II is filtration.
• C. C. Add reagent X in excess
• D. D. The reagent $Y$ is dilute hydrochloric acid.

Answer: A

23. Sodium borohydride is a white powder, commonly used as a reducing agent in organic synthesis, and decomposes in moist air. Sodium metaborate ( $\mathrm { NaBO } _ { 2 }$) is soluble in water, insoluble in ethanol, easily hydrolyzed, but can be stabilized under alkaline conditions. The procedure for making $\mathrm { NaBH } _ { 4 }$ from boron concentrate (which contains a certain amount of $\mathrm { B } _ { 2 } \mathrm { O } _ { 3 }$, and impurities such as $\mathrm { Al } _ { 2 } \mathrm { O } _ { 3 } , \mathrm { SiO } _ { 2 } , \mathrm { Fe } _ { 2 } \mathrm { O } _ { 3 }$), and analyzing the purity of a sample of $\mathrm { NaBH } _ { 4 }$ (with the impurity not taking part in the reaction) is as follows.  Step I : Take $\mathrm { mg } _ { \text {样品配成 } } 250 \mathrm {~mL} _ { \text {溶液 } }$, take $25.00 \mathrm {~mL} _ { \text {置于碘量瓶中,add } } \mathrm { V } _ { 1 } \mathrm { ml } \mathrm { c } _ { 1 } \mathrm {~mol} \cdot \mathrm {~L}$'s $\mathrm { KIO } _ { 3 \text { 溶液,发生反应:} } \mathrm { NaBH } _ { 4 } + \mathrm { KIO } _ { 3 } \rightarrow \mathrm { NaBO } _ { 2 } + \mathrm { KI } + \mathrm { H } _ { 2 } \mathrm { O }$ (the chemical equation is not leveled). Step II: Add excess $\mathrm { KI } _ { \text {溶液,调节 } } \mathrm { pH }$ to the solution from the reaction in Step I to convert $\mathrm { KIO } ^ { 3 }$ to $\mathrm { I } _ { 2 }$, cool, and leave in the dark for a few minutes. Step III: Adjust ${ } ^ { \mathrm { pH } }$ of the mixture obtained in Step II to weak acidity, add a few drops of starch solution, titrate with ${ } ^ { \mathrm { C } _ { 2 } } \mathrm {~mol} \cdot \mathrm {~L} ^ { - 1 } \mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 3 }$ standard solution to the end point, a reaction occurs: $\mathrm { I } _ { 2 } + 2 \mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 3 } = 2 \mathrm { NaI } + \mathrm { Na } _ { 2 } \mathrm {~S} _ { 4 } \mathrm { O } _ { 6 }$, consume $\mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 3 }$ standard solution $\mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 3 }$ and $\mathrm { Na } _ { 2 } \mathrm {~S} _ { 2 } \mathrm { O } _ { 3 }$. _14]] standard solution $\mathrm { V } _ { 2 } \mathrm {~mL}$ The purity of the sample is correctly calculated as

• A. A. $\frac { 15 \left( c _ { 1 } V _ { 1 } - \frac { 1 } { 6 } c _ { 2 } V _ { 2 } \right) } { 2 m } \%$
• B. B. $\frac { 57 \left( c _ { 1 } V _ { 1 } - \frac { 1 } { 2 } c _ { 2 } V _ { 2 } \right) } { 2 m } \%$
• C. C. $\frac { 57 \left( c _ { 1 } V _ { 1 } - \frac { 1 } { 6 } c _ { 2 } V _ { 2 } \right) } { 2 m } \%$
• D. D. $\frac { 15 \left( c _ { 1 } V _ { 1 } - \frac { 1 } { 2 } c _ { 2 } V _ { 2 } \right) } { 2 m } \%$

Answer: C

24. It is known that: (1) green tea contains a large amount of ellagic acid; (2) ferrous ellagic acid solution is colorless, ferric ellagic acid solution is blue-black. According to the analysis of the experimental process shown in the figure, the following description is wrong $\underset { \text { 叶水 } } { \text { 绿茶 } } \underset { \text {(1)add } } { \mathrm { FeSO } _ { 4 } }$ blue-black $\underset { \text {(2)add } } { \text { 维生素 } } \underset { \text { 原色 } } { \text { 恢复为 } } \underset { \text {(3)drop in } } { \mathrm { KSCN } \text { 溶液 } }$ no color change $\xrightarrow [ \text {(4)drop in } ] { \mathrm { H } _ { 2 } \mathrm { O } _ { 2 } \text { 溶液 } } \underset { \text { 红色 } } { \text { 变为 } }$

• A. A. Reaction (1) in which green tea leaf water reacts directly with $\mathrm { FeSO } _ { 4 }$ to form iron tannate which is blue-black in color
• B. B. Vitamin C in reaction (2) exhibits reducing properties
• C. C. In reaction (4) $\mathrm { H } _ { 2 } \mathrm { O } _ { 2 }$ can be replaced with freshly made chlorine water.
• D. D. Green tea leaf water should not be taken at the same time as iron supplements

Answer: A

25. It is known that: (1) green tea contains a large amount of ellagic acid; (2) ferrous ellagic acid solution is colorless, ferric ellagic acid solution is blue-black, generalized as shown in the figure of the experimental process analysis, the following description is wrong $\underset { \text { 叶水 } } { \text { 绿 } } \underset { \text {(1)add } } { \mathrm { FeSO } _ { 4 } } \underset { \text { 蓝黑色 } } { \text { Vitamin C } } \underset { \text {(2)add } } { \text { 恢复为 } } \underset { \text {(3)drop in } } { \mathrm { KSCN } \text { 溶液 } } \underset { \text {(4)drop in } } { \text { 不变色 } } \xrightarrow [ \text { 红色 } ] { \mathrm { H } _ { 2 } \mathrm { O } _ { 2 } \text { 溶液 } }$

• A. A. The ferrous ellagic acid produced by the reaction of green tea leaf water with $\mathrm { FeSO } _ { 4 }$ is easily oxidized to ferric ellagic acid, which is blue-black in color.
• B. B. Vitamin C reduces ferric ellagic acid to ferrous ellagic acid
• C. C. (2 reactions occur in (4)
• D. D. You should not drink green tea when taking iron supplements

Answer: C

28. Cadmium ferrite (mainly composed of $\mathrm { CdO } _ { 2 } , \mathrm { Fe } _ { 2 } \mathrm { O } _ { 3 } , \mathrm { Fe }$ and $\mathrm { SiO } _ { 2 }$) is used as a raw material for the preparation of analytical reagents $\mathrm { Cd } \left( \mathrm { BrO } _ { 3 } \right) _ { 2 }$. The process of $\mathrm { Cd } \left( \mathrm { BrO } _ { 3 } \right) _ { 2 }$ is shown in the figure $\left[ \mathrm { Cd } \left( \mathrm { SO } _ { 4 } \right) _ { 2 } \right.$ is soluble in water $]$:  The following statement is incorrect

• A. A. The acid leaching process involves both redox and non-redox reactions.
• B. B. $\mathrm { CH } _ { 3 } \mathrm { OH }$ is a reducing agent in the cadmium reduction step, and $\mathrm { Cd } ^ { 4 + }$ in solution may oxidize it to $\mathrm { CO } _ { 2 }$
• C. C. If bubbles are generated in the oxidation step, it means that ${ } ^ { \mathrm { H } _ { 2 } \mathrm { O } _ { 2 } }$ can also oxidize $\mathrm { CH } _ { 3 } \mathrm { OH }$ under acidic conditions.
• D. D. A small amount of $\mathrm { Cd } ^ { 2 + }$ remains in the filtrate after cadmium precipitation, which needs to be further recycled before discharge to prevent environmental pollution.

Answer: C

29. The electronics industry uses $\mathrm { FeCl } _ { 3 }$ solutions to etch copper foil from insulating boards to manufacture printed circuit boards. The process for recovering copper and ${ } ^ { \mathrm { FeCl } _ { 3 } }$ solids from the acid etching waste solution is as follows:  Known: $\mathrm { SOCl } _ { 2 } + \mathrm { H } _ { 2 } \mathrm { O } \square$ convex $\mathrm { SO } _ { 2 } \uparrow + 2 \mathrm { HCl } \uparrow$ The following analysis is incorrect

• A. A. Gases are produced in processes I, II, III, and V.
• B. B. The reactions that take place in the above process are replacement reactions, chemical reactions
• C. C. $V$ in $\mathrm { SOCl } _ { 2 }$ instead of direct heating and dehydration, mainly to avoid $\mathrm { FeCl } _ { 3 }$ hydrolysis.
• D. D. Add hydrochloric acid to II until no more bubbles are produced, then add ${ } ^ { \mathrm { H } _ { 2 } \mathrm { O } _ { 2 } }$ solution to the solution obtained by filtration to increase the $\mathrm { FeCl } _ { 3 }$ yield.

Answer: D

30. $\mathrm { MnO } _ { 2 }$ is an important inorganic functional material. The process of producing $\mathrm { MnO } _ { 2 }$ from crude $\mathrm { MnO } _ { 2 }$ (which contains the impurities MnO and $\mathrm { MnCO } _ { 3 }$) is shown in the figure.  The following analysis is incorrect

• A. A. The name of operation X and operation Y are both filtered.
• B. B. $\mathrm { CO } _ { 2 }$ is an acidic oxide, $\mathrm { MnO } _ { 2 }$ is a basic oxide.
• C. C. The ratio of the amount of substance of the oxidizing agent to that of the reducing agent in the process "oxidation" is $2 : 5$
• D. D. $\mathrm { Cl } _ { 2 }$ reacts with NaOH solution, transferring electrons per $42.6 \mathrm {~g} \mathrm { NaClO } _ { 3 }$ to $2 N _ { A }$

Answer: B

31. In the industrial treatment of zinc smelting residues from sphalerite (containing mainly $\mathrm { Zn } , \mathrm {~Pb} , \mathrm { Fe } , \mathrm { Ga }$ and other elements), the following process is designed for the extraction of lead, zinc and gallium. Known: $\mathrm { Ga } ( \mathrm { OH } ) _ { 3 } + \mathrm { OH } ^ { - } = \left[ \mathrm { Ga } ( \mathrm { OH } ) _ { 4 } \right] ^ { - }$  The process is incorrectly analyzed by

• A. A. Slag 1 is composed of Pb monomers.
• B. B. Reagent a is ZnO
• C. C. The main constituents of sludge 3 are $\mathrm { Fe } ( \mathrm { OH } ) _ { 3 }$
• D. D. The cathodic reaction of filtrate 3 undergoing electrolysis is $\left[ \mathrm { Ga } ( \mathrm { OH } ) _ { 4 } \right] ^ { - } + 3 \mathrm { e } ^ { - } = \mathrm { Ga } ^ { - } + 4 \mathrm { OH } ^ { - }$

Answer: A

32. The method of treating malaria contained in the Chinese medical text "After Elbow Prepared Emergency Formula", which is "one grip of artemisia, impregnate it with two liters of water, extract the juice by twisting it, and take it as much as you like", is a great inspiration for the research and development of artemisinin, a potent drug for malaria by Tu Youyou's team. Tu Youyou discovered that the ancient method was ineffective in comparative experiments, and she designed a process for extracting artemisinin that could be simplified as follows:  Analysis, the following judgment or narrative is certainly wrong ()

• A. A. Extracting active ingredients from natural plants to treat diseases is an important approach to drug development
• B. B. Crushing Artemisia annua can improve the extraction rate of active ingredients
• C. C. Artemisinin is soluble in water and ether.
• D. D. operation 1 is filtration, operation 2 is distillation

Answer: C

33. It is known that: (1) green tea contains a large amount of ellagic acid; (2) ferrous ellagic acid solution is colorless, ferric ellagic acid solution is blue-black. According to the analysis of the experimental process shown in the figure, the following description is wrong ( ) 

• A. A. The ferrous tannate produced by the reaction between green tea leaf water and ferrous sulfate is easily oxidized to ferric tannate and becomes blue-black in color.
• B. B. Vitamin C in reaction (2) exhibits oxidizing properties
• C. C. In reaction (4) $\mathrm { H } _ { 2 } \mathrm { O } _ { 2 }$ can be replaced with freshly made chlorine water.
• D. D. Green tea leaf water should not be taken at the same time as iron supplements

Answer: B

34. Potassium pertechnate $\left( \mathrm { K } _ { 2 } \mathrm { FeO } _ { 4 } \right)$ is an environmentally friendly, highly efficient, multi-functional drinking water treatment agent. It is an environmentally friendly, highly efficient and multi-functional drinking water treatment agent, which is made from waste iron filings (mainly into A process of preparing $\mathrm { K } _ { 2 } \mathrm { FeO } _ { 4 }$ from waste iron filings (the main component is Fe, containing a small amount of $\mathrm { Fe } _ { 2 } \mathrm { O } _ { 3 } , \mathrm { FeO }$, etc.) is shown in the figure. The following statement is correct ( )  $$ \mathrm { NaClO } > \mathrm { Na } _ { 2 } \mathrm { FeO } _ { 4 } $$

• A. A. In the process of "acid leaching and oxidizing", the higher the temperature, the more favorable the reaction is
• B. B. Oxidizing properties under alkaline conditions;
• C. C. Solubility of the substance under the condition: $\mathrm { Na } _ { 2 } \mathrm { FeO } _ { 4 } < \mathrm { K } _ { 2 } \mathrm { FeO } _ { 4 }$
• D. D. The chemical reactions involved in this process are all redox reactions

Answer: B

35. Cuprous chloride $( \mathrm { CuCl } )$ is widely used in chemical, printing and dyeing, electroplating and other industries. The process designed for the preparation of CuCl in industry using copper sulfide concentrate as raw material is shown in the figure:  Known: CuCl is insoluble in ethanol, easy to hydrolyze when wet. The following statement is correct ( )

• A. A. Step (1) roasting produces toxic gases that can make purple litmus solution first turn red and then fade, reflecting bleaching properties
• B. B. If nitric acid is used instead of sulfuric acid in step (2), it will affect the yield of CuCl
• C. C. Step (3) occurs as a complex decomposition reaction
• D. D. Step (4) uses an ethanol wash and can also be washed with distilled water

Answer: B

36. A process for the preparation of iron red using magnetite ${ } ^ { \left( \mathrm { Fe } _ { 3 } \mathrm { O } _ { 4 } \right.}$ is as follows:  The following statement is correct ( )

• A. A. A small amount of acidic $\mathrm { KMnO } _ { 4 }$ solution is added dropwise to filtrate A, and the purple color fades.
• B. B. The presence of $\mathrm { Fe } ^ { 2 + }$ in filtrate A can be tested with KSCN solution and chlorine water.
• C. C. $\mathrm { FeCO } _ { 3 }$ The reaction equation for calcination in air is $\mathrm { FeCO } _ { 3 } \xlongequal { \text { 煅烧 } } \mathrm { FeO } + \mathrm { CO } _ { 2 } \uparrow$
• D. D. The mass of Fe in the final iron red is less than the mass of Fe in the original magnetite.

Answer: A

37. China's chemist Hou Debang proposed the famous Hou's alkali method, which has made outstanding contributions to the world's alkali industry. An experimental group simulated the process of Hou's alkali production method as shown in the figure.  ## The following statements are correct ( )

• A. A. Order of gas introduction into saturated brine: $\mathrm { NH } _ { 3 }$ then $\mathrm { CO } _ { 2 }$.
• B. B. "Operation a" is a distillation that takes advantage of the large difference in boiling points between $\mathrm { NaHCO } _ { 3 }$ and $\mathrm { NH } _ { 4 } \mathrm { Cl }$.
• C. C. Thermal stability: $\mathrm { NaHCO } _ { 3 } > \mathrm { Na } _ { 2 } \mathrm { CO } _ { 3 }$
• D. D. The $\mathrm { Ba } ( \mathrm { OH } ) _ { 2 }$ solution can be used to identify $\mathrm { Na } _ { 2 } \mathrm { CO } _ { 3 }$ and $\mathrm { NaHCO } _ { 3 }$.

Answer: A

38. Chemical expert Hou Debang has made important contributions to China's soda ash industry, Hou's alkali method of the main process shown in the figure (some substances have been omitted). The following statement is wrong ( ) 

• A. A. Gas $a$ is $\mathrm { NH } _ { 3 }$ and gas $b$ is $\mathrm { CO } _ { 2 }$.
• B. B. Operation I and II are filtered
• C. C. The ionic equation that generates $\mathrm { NaHCO } _ { 3 }$ is $\mathrm { NH } _ { 3 } + \mathrm { H } _ { 2 } \mathrm { O } + \mathrm { CO } _ { 2 } = \mathrm { HCO } _ { 3 } ^ { - } + \mathrm { NH } _ { 4 } ^ { + }$
• D. D. Gas c and mother liquor 2 can be recycled

Answer: C

39. Ammonia is an important chemical raw material, industrial ammonia synthesis process shown in the figure below. The following analysis of the role of the regulation of production conditions is not correct ( ) 

• A. A. The "purification" in step (1) prevents poisoning of the catalyst.
• B. B. Step (2) "pressurization" can speed up the reaction rate, the ammonia yield will also increase, the higher the pressure the better in industrial production
• C. C. Step (3) is generally chosen to control the reaction temperature to $400 \sim 500 ^ { \circ } \mathrm { C }$ because the catalyst activity is maximum at this temperature
• D. D. Step (4) can be separated by rapid cooling to liquefy the ammonia

Answer: B