[The test center meets the standards and practices in class].
1 The following statement is true.
A Naclo, H2O2, chlorine water, all have a bleaching effect, and the bleaching principle is the same.
b Concentrated nitric acid and concentrated hydrochloric acid are volatile and must be stored in brown reagent bottles.
c The fixation process of nitrogen is the process in which nitrogen is oxidized and oxidation reactions occur.
d Most non-metallic oxides are acidic oxides that react with alkalis to form salts and water.
2.In the following reactions, nitric acid exhibits both acidity and oxidation ( ).
a Turns litmus solution red.
b Reacts with copper to release no gas to generate Cu(NO3)2
c Reacts with Na2CO3 to release CO2 gas to form NaNo3
D When mixed with S elemental and co-heated, H2SO4 and NO2 are generated
3. The same quality of copper nitrate is prepared by the following three ways: copper reacts with concentrated nitric acid, copper reacts with dilute nitric acid, copper reacts with oxygen to form copper oxide, and copper oxide reacts with dilute nitric acid. The following statement is correct ( ).
a The amount of copper consumed by the three pathways is not equal.
b The amount of nitric acid consumed by the three pathways is equal.
c The amount of copper consumed by the substance: the pathway the pathway the pathway
d The amount of nitric acid consumed: the pathway the pathway the pathway
4. Divide the gas produced by the co-heating of the red-hot charcoal and concentrated nitric acid into two parts, the first part is first through an appropriate amount of distilled water, and then through a small amount of clear lime water; The first part is directly through a small amount of clarified lime water. then the change in lime water is most likely ( ).
a does not become turbid, becomes turbid.
b Becomes turbid, does not change turbidity.
c Becomes cloudy, becomes cloudy.
d Constant turbidity, constant turbidity.
5 Of the following descriptions of experimental phenomena, the correct one is ( ).
a Copper flakes are injected into dilute nitric acid, producing large amounts of reddish-brown gas.
b Put the iron sheet into the cold dilute nitric acid, the iron sheet does not dissolve.
c The test tube filled with NO2 is upside down in the water tank, the color of the gas in the test tube becomes light until it is colorless, and the water fills the whole test tube.
d Open the cap of the bottle containing concentrated nitric acid, and a white mist appears.
6 The following concerning experimental operations, phenomena, and explanations or conclusions are correct ( ).
7 An enterprise uses the following process to comprehensively treat the flue gas containing SO2 emitted by the factory to reduce the pollution caused by the plant. The following statement is correct ( ).
a.The reaction that occurs in the sulfur dioxide absorption tower is SO2 SO32- H2O===2HSO3-
b.The reaction that occurs in the ammonia absorption tower is HSO3- OH ===H2O SO32-
c.The above process uses the principle of redox reaction.
d.SO2 can be recycled in the above process.
8 The ratio of the amount of the substance is 2 5 zinc reacts with dilute nitric acid, if the product of nitric acid is reduced is N2O, and there is no zinc left after the reaction, then the ratio of the amount of reduced nitric acid to the amount of non-reduced nitric acid in the reaction is ( ).
a．1∶4 b．1∶5 c．2∶3 d．2∶5
9 When a certain concentration of dilute Hno3 reacts with metal M, +2 valent nitrate can be obtained, and the ratio of the amount of M to Hno3 during the reaction is 5 12, then the reduction product of Hno3 during the reaction is ( ).
a．nh4no3 b．n2
c．n2o d．no
10 14 g copper-silver alloy completely reacts with a certain amount of nitric acid solution of a certain concentration, and the released gas is combined with 112 l (under standard conditions) of oxygen mixed into the water, and exactly all of it is absorbed by the water, then the mass of copper in the alloy is ( ).
a.9.6 gb.6.4 g c.4.8 g d.3.2 g
11 In 100 mL of the mixture, the concentrations of Hno3 and H2SO4 were 04 moll and 01 mol l, add 192 g of copper powder, after heating and sufficient reaction, the amount concentration of Cu2 in the obtained solution is ( ).
a．0.15 mol/l b．0.225 mol/l
c．0.35 mol/l d．0.45 mol/l
12. Experiments on the reaction of copper and nitric acid were carried out using the device shown in the figure below.
1) Nitric acid is generally contained in a brown reagent bottle, please use a chemical equation to explain the reason:
2) Experiments with dilute nitric acid: after the reaction starts, the copper wire gradually thins, bubbles are generated, and the solution turns blue.
The ionic equation for the reaction of copper with dilute nitric acid is
A reddish-brown tinge color was observed in the test tube, the reason for which was expressed in a chemical equation).
3) Experiments with concentrated nitric acid: the reaction is carried out vigorously, the copper wire gradually thins, the solution turns green, and reddish-brown gas appears above the test tube.
The chemical equation for the reaction of copper with concentrated nitric acid is
A student speculated that the reason why the solution was green after the reaction was that the solution reached saturation, the saturated solution was yellow, the copper nitrate solution was blue, and the two were green after mixing. He takes a small amount of this green solution and adds an appropriate amount of water to it when the solution turns blue, probably because it is expressed by a chemical equation).
13 The study of the properties of substances by using the valency of elements and the relationship between the types of substances is an important method to learn the knowledge of elemental compounds. The figure shows a two-dimensional relationship between the common valencies of nitrogen and the common types of substances.
1) The laboratory commonly uses hydrated lime and I co-heating to make A, please write the reaction equation
2) Among the nitrogen oxides in the figure, the chemical formula of the useful substances that belong to the acid oxides is answered).
3) J is mainly used in dyes, medicine, printing and dyeing, bleaching, etc., and the flame color reaction of J is yellow. j can cause the acidic solution to fade (generated), and the ionic equation for this reaction is
4) One way to control the pollution of nitrogen oxides in automobile exhaust is to install a catalytic conversion device containing A in the exhaust pipe of the car, and C and A in the exhaust gas are converted into non-toxic and non-polluting emissions under the action of catalysts. The chemical equation for this reaction is
5) In the industry, A is used as raw material to produce H, and the reaction route is, assuming that the conversion rate of nitrogen in the whole process is reached, then the concentrated nitric acid with a mass fraction of 25 kg is produced per day, and the volume under the standard condition of total consumption is
14..There is 1 rainwater sample, and the pH of the rainwater sample is measured at regular intervals, and the data obtained are as follows:
1) Analyze the data and answer the following questions:
The reason for the pH change of rainwater samples is:
expressed in chemical equations).
If the rainwater that has just been sampled is mixed with tap water, the pH will change to the cause
expressed in chemical equations).
2) Among the following measures, the way to reduce the generation of acid rain is to fill in the letters).
Reduce the use of coal as fuel, make factory chimneys high, desulfurize fuel, add lime to acidified soil, and develop new energy sources.
a.①②b.②③c.①③d.①③
15.Altay City, Xinjiang, with its unique climatic conditions and excellent air quality, has become the eighth national atmospheric background monitoring point in China. The monitoring equipment installed at the monitoring points can monitor air pollutants such as sulfur dioxide, nitrogen dioxide, and nitric oxide on a daily basis.
1) Automobile exhaust gas (including CO, SO2, NO, etc.) is one of the sources of urban air pollution, and one of the treatment methods is to install a "catalytic converter" (with platinum and palladium alloy as catalysts) on the exhaust pipe of the car, which can make carbon monoxide react with nitric oxide to produce non-toxic gases that can participate in the atmospheric circulation.
The main substances in car exhaust that cause the formation of acid rain are:
Please write the chemical equation for the main reaction that forms nitric acid rain:
Installing a "catalytic converter" on the exhaust pipe of a car can make the reaction of CO and NO produce a non-toxic gas that can participate in the atmospheric circulation, please write the chemical equation of the reaction:
Among the following options, reasonable measures to control air pollution in the city are filled).
a.Make the most of solar energy and reduce the burning of fossil fuels.
b.Use electric vehicles to reduce gasoline consumption.
c.People are not allowed to travel.
d.Wear a breathing mask.
2) In the laboratory, the tail gas containing nitrogen oxides is generally absorbed with NaOH solution.
If NO2 is absorbed with NaOH solution, sodium salts containing 2 nitrogen-containing elements can be generated, please write the chemical equation:
The mixture of NO2 and NO® can also be absorbed by NaOH solution to produce only one salt, please write the chemical equation:
[The test center meets the standards and practices in class].
Answer] D Detailed Explanation].
The bleaching of a Naclo, H2O2 and chlorine is bleaching because of oxidation, and the bleaching principle of sulfur dioxide is to combine with organic color, which belongs to the chemical process, and the color will be restored when heated, and the principle is different, so A is wrong;
B concentrated HNO3 is a liquid that is easy to decompose when seeing light, so it should be stored in a brown glass bottle, concentrated hydrochloric acid is volatile, but relatively stable, it can be sealed and stored, and it does not need to be stored in a brown reagent bottle, so B is wrong;
c The compound that converts the free state of nitrogen into nitrogen is called nitrogen fixation, such as N2 NH3, the valency of nitrogen atoms is reduced from 0 to -3 valence, and a reduction reaction occurs, so C is wrong;
d Most non-metallic oxides are acidic oxides, which can react with alkali to form salt and water, such as CO2, and can react with NaOH solution to form sodium carbonate and water, so D is correct; Therefore, d.
Answer] B Analysis] Item A, HNO3 only shows acidity; In item b, when Cu reacts with dilute nitric acid, part of it plays the role of acid to form Cu(NO3)2, and part of it is reduced to No as an oxidant; C, 2Hno3 Na2CO3===CO2 H2O 2nano3, HNO3 only showed strong acidity; In terms D, HNO3 oxidizes S to H2SO4 and reduces itself to NO2, in which HNO3 only exhibits strong oxidation.
Answer] D Analysis] Related reactions: Cu 4Hno3 (concentrated) ===Cu (No3)2 2NO2 2H2O
3cu 8hno3 (dilute) ===3cu (no3)2 2no 4h2o
2Cu O2=2Cuo, Cuo 2Hno3 (dilute) ===Cu(No3)2 H2O
Analyzing the above three sets of reactions, it can be seen that the same mass of Cu(NO3)2 is generated, the same mass of copper is consumed, but the mass (or amount of substance) of nitric acid is not the same, and the pathway consumes the most Hno3, followed by the pathway, and consumes the least Hno3. Through comparison, it can be seen that the production of Cu(NO3)2 has the best effect, which does not cause pollution and can improve the utilization rate of Hno3.
Answer] B Explained].
C reacts with concentrated nitric acid to produce a mixed gas of CO2 and NO2, the mixed gas directly reacts with clarified lime water, and NO2 reacts with water to generate nitric acid, and nitric acid reacts with calcium hydroxide first, and it is difficult to obtain CaCO3 precipitation; The mixed gas first passes through water, NO2 can react with water to form nitric acid and NO, NO2 and CO2 mixed gas, and then through the clarified lime water, NOs do not react with calcium hydroxide, and carbon dioxide reacts with calcium hydroxide to produce CaCO3 precipitation, so B is selected.
Answer] D Detailed Explanation].
a.Copper reacts with dilute nitric acid to form NO, which is a colorless gas, so A is wrong;
b.Iron and dilute nitric acid can react to form ferric nitrate, water and nitric oxide, which react with concentrated nitric acid for passivation, so b is wrong;
c.Nitrogen dioxide can react with water to form nitric oxide and nitric acid, and the color of the gas becomes light until it is colorless, but nitric oxide is insoluble in water, so the liquid cannot fill the entire test tube, so c is wrong;
d.Concentrated nitric acid is volatile, and can form acid mist when combined with water vapor in the air, so d is correct;
Answer: D.
Concentrated nitric acid has strong oxidation, instability and acidity, and is easy to decompose into nitrogen dioxide, oxygen and water when heated, nitrogen dioxide can react with water to form nitric oxide and nitric acid, nitric oxide is a colorless and insoluble gas, so as to answer this question.
Answer] B Analysis] Dilute nitric acid reacts with iron powder, iron is first oxidized to Fe3, excess iron powder reduces Fe3, and finally Fe2 is obtained, dropping into KSCN solution does not show red, item A is wrong; At room temperature, Fe and Al were passivated in concentrated HNO3 or concentrated H2SO4, and a dense oxide protective film was formed to prevent the reaction, and item b was correct. Al foil can react with dilute Hno3 to release gas, and the C term is wrong.
Answer] A analysis] sulfur dioxide is absorbed with (NH4)2SO3 solution, and the ionic reaction that occurs is SO2 SO32- H2O===2HSO3-, so item A is correct; The reaction that occurs in the ammonia absorption tower is HSO3- NH3·H2O===NH4+ SO32- H2O, so item B is wrong. There is no change in the valency of the elements in each reaction in the description process, which is not a redox reaction, so item c is wrong; The description process absorbs SO2 and cannot be recycled, so item D is wrong.
Answer] A Analysis] Let 2 mol Zn participate in the reaction, because there is no Zn left, then 2 mol Zn(NO3)2 is finally generated, which obviously contains 4 mol NO3-, which is Hno3 that does not participate in the redox reaction; The valency of N element in the process of Hno3 N2O is 5 valence 1 valence, according to the conservation of gain and loss electrons: 2 N(Zn) N(Hno3) 4, then N(Hno3) 1 mol, that is, 1 mol of Hno3 is reduced.
Answer] B Explained].
According to the topic, the reaction equation can be listed as follows: 5m+12hno3=5m(NO3)2+N2 +6H2O, when a dilute Hno3 reacts with metal M, +2 valence nitrate can be obtained, so 1mol m loses 2mol electrons, and 5mol m loses 10mol electrons; In 12mol HNO3, 10mol nitric acid did not participate in the redox reaction, only 2mol nitric acid participated in the redox reaction, and 10mol electrons were obtained, and the valency of nitrogen in nitric acid was +5 valence, so the reduction product must be 0 valence N2, and the b term was correct;
Answer] D Analysis] The reaction process between copper-silver alloy and Hno3 is as follows:
The reaction between Cu, Ag and Hno3 is a redox reaction, Cu and Ag lose electrons, and HNo3 gains electrons to form No2 or No. Since NO2, NO2, and O2 are all absorbed by water to form HNO3, that is, NO2 and NO2 transfer electrons to O2, so in the whole reaction process, it is equivalent to the transfer of electrons lost by Cu and Ag to 005 mol o2,0.05 mol O2 to obtain the amount of electronic species = 005 mol×4=0.2 mol。Let the quantity of the substance of Cu be x and the quantity of the substance of ag be y, then there is:
So the mass of copper m(cu) = 005 mol×64 g·mol-1=3.2 g。
Answer] B
Answer] 1) 4Hno3 = 4NO2 +O2 +2H2O
2）3cu+8h++2no3-=3cu2++2no↑+4h2o 2no+o2=2no2
3) Cu + 4 Hno3 (concentrated) = Cu (No3) 2 + 2 No2 + 2H2O 3 No2 + H2O = 2Hno3 + No
Analysis] 1) Nitric acid is easy to decompose when seen by light, and is generally contained in a brown reagent bottle.
2) Using dilute nitric acid for experiments, the copper wire is oxidized and gradually thinned, nitric oxide gas is generated, and bubbles are generated, and the copper nitrate solution is blue.
3) Using concentrated nitric acid for the experiment, the copper wire is oxidized and gradually tapered, and the reddish-brown gas above the test tube is NO2, indicating that the solution is a saturated solution of NO2, because the saturated solution of NO2 is yellow, the copper nitrate solution is blue, and the solution turns green after mixing the two.
1) Nitric acid is generally contained in a brown reagent bottle, because nitric acid is easy to decompose when seen by light, and the chemical equation is: 4Hno3 = 4NO2 + O2 + 2H2O.
2) Copper reacts with dilute nitric acid to form nitric oxide, and the ion equation is: 3Cu+8H++2NO3-=3Cu2++2NO+4H2O;
In the experiment, it was observed that the gas in the test tube was slightly reddish-brown, because the colorless NO2 gas generated by the reaction reacted with the oxygen in the test tube to form reddish-brown NO2, the chemical equation: 2NO+O2=2NO2.
3) Copper reacts with concentrated nitric acid to form nitrogen dioxide, and the chemical equation is: Cu+4Hno3(concentrated)=Cu(NO3)2+2NO2 +2H2O;
After adding an appropriate amount of water, the NO2 in the saturated solution reacts with water to form nitric acid and nitric oxide, and the yellow color of the NO2 saturated solution in the original solution fades, showing the blue color of the copper nitrate solution, and the chemical equation: 3NO2 + H2O = 2HNO3 + NO
Answer] 1) 2NH4Cl+Ca(OH)2=CaCl2+2NH3 +2H2O
2）n2o3、n2o5
3）5no2‑+2mno4++6h+=5no+2mn2++3h2o
4）4nh3+6no=5n2+6h2o
Analysis] According to the valency and substance types of N elements in the figure, A, B, C, D, E, F, G, and H are NH3, N2, NO, N2O3, NO2 or N2O4, N2O5, HNO2, and HNO3, and I, J, and K are ammonium salts, nitrites, and nitrates, respectively.
1) Hydrated lime is the common name of calcium hydroxide, calcium hydroxide and ammonium chloride are coheated to generate calcium chloride, ammonia and water, the equation is 2NH4Cl + CA (OH) 2 = CACl2 + 2NH3 + 2H2O;
2) N oxides in the figure: NO, N2O3, NO2 or N2O4, N2O5, NO is not a salt oxide, NO2 or N2O4 and the base will undergo redox reaction to form nitrate, water and NO, which do not belong to acidic oxides, only N2O3 and N2O5 belong to acidic oxides, and react with NaOH to form nano2 and water, nano3 and water respectively, so the answer is: N2O3, N2O5;
3) j is nano2, nano2 is oxidized by acidic kmno4 to form sodium nitrate, kmno4 is reduced to form mn2+, and the ion equation is 5no2-+2mno4-+6h+=5no+2mn2++3h2o;
4) Under catalysis, ammonia reacts with nitric oxide to form nitrogen and water, and the chemical equation is 4NH3+6NO=5N2+6H2O;
5) NH3 NO NO2 HNO3, the conversion rate of nitrogen in the whole process is 100%, then the reduction reaction of NH3 HNO3 8E-, 1MOLo2 is conserved by N atoms and 4mol electrons are transferred, then the relationship is HNO3 8E- 2O2, N(HNO3)=M M=25 63% 1000g (63G mol)=250mol, that is, N(O2)=2N(HNO3)=2 250mol=500mol, and V(O2) under standard conditions)=nvm=22.4l/mol×500mol=11200l=11.2m3。
Answer] (1) SO2 H2O=H2SO3,2H2SO3 O2===2H2SO4 Small Cl2 2H2O SO2===H2SO4 2HCl or H2SO3 HCO===H2SO4 HCl (2)C
Analysis] 1) The pH becomes smaller when acid rain is placed, which is caused by the oxidation of H2SO3 in rainwater by oxygen in the air: SO2 H2O=H2SO3, 2H2SO3 O2===2H2SO4.
When rainwater and tap water are mixed, the reaction of SO2 with Cl2 (or H2SO3 with HCl) should be considered: SO2 2H2O Cl2===H2SO4 2HCl (or H2SO3 HClo===H2SO4 HCl). Therefore, when rainwater is mixed with tap water, the pH of the solution will become smaller.
2) To reduce the generation of acid rain, it is necessary to reduce SO2 emissions, convert coal into clean energy (such as coal gasification and liquefaction), fuel desulfurization, sulfur fixation, and develop new sulfur-free energy sources (such as hydrogen energy, nuclear energy, etc.). Therefore correct.
1) SO2 and NO 2NO O2===2NO2 H2O===2HNO3 NO
2co＋2no=2co2＋n2 ④ab
2)①2no2＋2naoh===nano3＋h2o＋nano2
no＋no2＋2naoh===2nano2＋h2o
Analysis] 1) According to the information given in the question, it can be seen that the non-toxic gases that can participate in the atmospheric circulation are CO2 and N2 when CO reacts with NO, so the chemical equation of the reaction is 2CO2NO=2CO2 N2. (2) The two nitrogen-containing sodium salts formed by the reaction of NO2 and NaOH solution are nano2 and nano3, and the chemical equation is 2NO2 2NaOH===nano2 nano3 H2O. NO2 (N element 4 valence) and N (N element 2 valence) react with NaOH solution to form only one salt, according to the redox reaction law, it can be known that the salt is nano2 (N element 3 valence), and the chemical equation is No No2 2Naoh===2nano2 H2O.