(This test includes 53 small questions. The answer time is 2.5 hours. )
For multiple-choice questions, the answers are all single-choice, and the letters indicating the correct answers are written on the horizontal lines.
1. δ, a symbol commonly used in chemical manuals, means _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
2. Indicate the color of the chemical reagent label at the following levels:
(a) Excellent purity _ _ _ _ _ _ _ _ (b) Analytical purity _ _ _ _ _ _ _ _ (c) Chemical purity _ _ _ _ _ _ _ _
(d) Reference reagent _ _ _ _ _ _ _
3. The color of oxygen, nitrogen, hydrogen and air bottles is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
4. There are national standards for laboratory water use. According to the resistivity index of water, the best water quality is _ _ _ _ _ _ _ _ _ _.
(A) 1mω。 cm(B) 18mω。 cm(C) 10mω。 cm(D)0.2mω。 centimetre
5. Draw a picture to mark the ground wire, live wire and zero wire of the three-hole electrical socket commonly used in the laboratory.
Drawing room:
6. If the electrical appliances in the laboratory are on fire, the fire extinguishing method is _ _ _ _ _ _ _ _ _ _ _.
(a) Put it out with sand immediately; (b) After cutting off the power supply, put it out with foam extinguisher; (c) Put it out with water immediately.
(d) Immediately put out the fire with a CO2 fire extinguisher after cutting off the power supply.
7, metal sodium should be stored in _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _; Yellow phosphorus should be stored in _ _ _ _ _ _ _ _ _ _ _ _ _ _.
8. The harmless treatment methods for sodium cyanide and spilled mercury drops are _ _ _ _ _ _ _ _ _ _ and _ _ _ _ _ _ _ _ _.
9. When opening the nitrogen cylinder, the laboratory has the following operations:
(a) Open the high-pressure air valve (b) and observe the reading of the low-pressure meter (c). Tighten the pressure reducer lever clockwise (D) and observe the reading of the high pressure meter.
The correct operation sequence is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
10, when measuring temperature with thermocouple, in order to keep the cold end temperature stable, it must be _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _; Several groups of thermocouples are often used in series for the purpose of _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
1 1. In the thermostatic bath, the function of mercury contact thermometer is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
(a) temperature measurement and temperature control (b) temperature measurement (c) temperature control (d) is neither temperature measurement nor temperature control.
12, in the electrochemical kinetics experiment with _ _ _ _ _ _ _ _ _ _ _ _ to measure the potential of the electrode. (a) Voltmeter (b) Potentiometer (c) Digital voltmeter with high input impedance
13, the conversion reaction of sucrose is: c12h22o1(sucrose) +H2O→C6H 12O6 (glucose) +C6H 12O6 (fructose). In kinetic research, because _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _, it can be treated as a first-order reaction.
14. in the saponification reaction of ethyl acetate, if the concentrations of reactant CH3COOC2H5 and NaOH solution are both 0.010 mol l-1,the conductivity of the system at the beginning of the reaction after equal volume mixing can be _ _ _ _ _ _ _ _ _ _ _ _.
(a) 0.010mol l-1NaOH solution; (b) 0.005 mol l- 1 ch3cooh solution.
(C) 0.005 mole. L- 1 sodium hydroxide solution (D) 0.005 mol. L- 1 CH3COONa solution.
15. After mixing the following two solutions with the same concentration in equal volume, it is _ _ _ _ _ _ _ _ _ _ _ _ _.
(a) ammonia+acetic acid (b) sodium hydroxide+acetic acid (c) sodium hydroxide+hydrochloric acid (d) hexamethylenetetramine+hydrochloric acid.
16. The following standard solutions can be prepared by direct method: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
(a) potassium permanganate (B) K2Cr2O7 (C) sodium hydroxide (d) ferrous sulfate.
17. When iron is determined by gravimetric method, _ _ _ _ _ _ _ _ _ _ _ _ _ _.
(a) Fast quantitative filter paper (b) Slow quantitative filter paper (c) Medium quantitative filter paper (d) Glass sand core funnel
18. The measure to eliminate the systematic error in the determination method is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
Increase the number of parallel determinations; (b) Weighing more than 0.2g of samples; (c) carrying out control experiments with standard samples; (d) Conduct the experiment carefully.
19, the following four solutions, each diluted with water 10 times, the biggest change in pH value is _ _ _ _ _ _ _ _ _ _ _.
0. 1 mol. L- 1 HAc + 0. 1 mol。 L- 1 sodium acetate (B) 0. 1 mol. L- 1 HAc
(C) 0.0 1 mol. L- 1 HAc + 0.0 1 mol。 L- 1 sodium acetate 0. 1 mol. L- 1 hydrochloric acid
20. The molar absorption coefficient (ε) of colored complex is related to the following factors: _ _ _ _ _ _ _ _ _ _ _ _ _ _.
(a) thickness of absorption cell (b) wavelength of incident light (c) concentration of colored complex (d) stability of complex.
2 1. In the following titration, when the concentrations of titrant and drippings are increased by 10 times, the jumping range is the largest in _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
(A) HCl titration weak base (B) EDTA titration Ca2+ (C) Ce4+ titration Fe2+ (D) AgNO3 titration NaCl.
22. In complexometric titration, when Al3+ is determined by the back-dropping method, the standard solution of the following metal ions is _ _ _ _ _ _ _ _ _ _ _ _ _ _.
Zn2+ (B) Mg2+ (C) Ag+ (D) Bi3+
23. The iron content of an iron ore is about 40%, and the measurement error is required to be less than or equal to 0.3%, so _ _ _ _ _ _ _ _ _
(a) phenanthroline colorimetry (b) sulfosalicylic acid photometry (c) atomic absorption spectrometry (D) K2Cr2O7 titration.
24. Determine the content of Pb3O4 in the sample by gravimetric method, and accurately weigh the obtained PbSO4.
Use this weight to calculate the content in the sample. It is correct to express the weight coefficient in _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
(A)3M(pbso 4)/M(pb3o 4)(B)M(pbso 4)/M(pb3o 4)
(C)M(pb3o 4)/3M(pbso 4)/D)3M(Pb)/M(pb3o 4)
25. In constant analysis, if the relative error of the determination result is required to be ≤ 0.65438 0%, the titrant volume should be controlled in _ _ _ _ _ mL and the sample weighing should be controlled in _ _ _ _ _ _ g.
26, the pH of the solution = 7.200, which has _ _ _ _ _ significant digits; The hydrogen ion activity (a(H+)) of this solution is _ _ _ _ _ _ _.
27. The approximate concentrations of the following commercially available reagents are:
H2SO4 _ _ _ _ mol l-1,HNO3 _ _ _ _ mol l-1,HCl _ _ _ _ mol l-1ammonia _ _ _ _ _ mol.
28, visible spectrophotometer commonly used light source is _ _ _ _ _ _, absorption pool material is _ _ _ _ _;
The common light source of ultraviolet spectrophotometer is _ _ _ _ _ _ _ _ _, and the material of absorption pool is _ _ _ _ _ _ _ _;
The light source commonly used in fluorescence analyzer is _ _ _ _ _ _ _ _ _, and the material of absorption cell is _ _ _ _ _ _ _ _ _ _.
29, the highest gas flame temperature area is _ _ _ _ _.
(a) Oxidation Flame Zone (b) Reduction Flame Zone (c) Flame Core Zone (d) The area near the reduction flame in the oxidation flame zone.
30. When a substance is precipitated from an aqueous solution containing the following ions, it is necessary to check whether the ions adsorbed on the solid surface have been washed clean and whether _ _ _ _ _ _ _ _ _ _ _ _.
(A) Mg2+ (B) Na+ (C) Cl- (D) SO42-
3 1. Use a 25ml pipette to suck the nominal volume of solution from the volumetric flask and transfer it to the conical flask, so that the volume of solution in the volumetric flask will be reduced by _ _ _ _ _ _.
(a) equal to 25.00 ml; (b) greater than 25.00 ml; (c) less than 25.00 ml.
32. Among the following salts, _ _ _ _ is the most soluble in water.
(a) strontium oxalate (b) magnesium sulfate (c) calcium phosphate (d) barium carbonate.
33, the following three reactions in the same solution system:
①Cl2+2\ = 2cl\+I2
②Cl2+2br\ = 2cl\+Br2③5cl 2+I2+6H2O = 10cl\+2io 3\+ 12H+
The correct order of "starting the reaction" is _ _ _ _ _.
(A) ①>②>③ (B) ①>③>② (C) ③>②>①
34. Add concentrated NaOH solution to the Sn2+ solution, and the color of the precipitate is _ _ _ _ _.
(a) White (b) Gray (c) Black (d) White gradually turns black (e) White gradually turns yellow.
35, NH3, HCl, CO2, H2S, N2 and other gases in water solubility order is _ _ _ _.
(A)NH3 & gt； HCl & gtCO2 & gtH2S & gt； N2(B)HCl & gt； NH3 & gtCO2 & gtH2S & gt； N2
(c) hydrochloric acid > NH3 & gtH2S >; CO2 & gtN2·H2S & gt； HCl & gtCO2 & gtNH3 & gtN2
36. Alumina sintered at high temperature (≥ 1000℃).
(a) Soluble in concentrated hydrochloric acid (b) Soluble in concentrated nitric acid (c) Soluble in hydrofluoric acid (d) Insoluble in concentrated hydrochloric acid, concentrated nitric acid and hydrofluoric acid.
37. Zinc reacts with nitrate in concentrated sodium hydroxide solution to form _ _ _ _ _.
(A) NO2 (B) NO (C) N2 (D) H2 (E) NH3
38, determination of the melting point of organic compounds, when the temperature rises to 10- 15℃, the heating rate should be controlled in _ _ _ _ _.
39. The reason why the liquid rushed out of the separatory funnel was _ _ _ _ _ _ _ _. To prevent this phenomenon, it should be _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
40. After vacuum distillation stops receiving fractions, the order of ending vacuum operation is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
4 1 and * * * boilers have definite composition and boiling point. Because they are the same, they cannot be separated and purified by fractionation.
42. Substance A and B are separated by paper chromatography. It is known that the specific displacement values of components A and B are 0.65 and 0.45 respectively. If the length of chromatographic paper is 20cm, the maximum distance between spots after A and B chromatography is 0.
(a) 5.0cm (b) 4.0cm (c) 3.0cm (d) 2.0cm.
43. When measuring the melting point of solids, the possible reason for the high melting point is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
(a) There are impurities in the sample; (b) the sample is not dry; (c) The capillary wall used is too thick; (d) The temperature rises too slowly during the measurement.
44. After the reaction of isoamyl alcohol and glacial acetic acid to synthesize isoamyl acetate catalyzed by sulfuric acid is completed, the reasonable step of subsequent treatment is _ _ _ _ _ _ _ _.
(a) water washing, alkali washing, acid washing and brine washing (b) alkali washing, acid washing and water washing (c) water washing, alkali washing and brine washing; (d) alkaline washing and brine washing
45. When the components of multicomponent liquid organic matter have similar boiling points, the most suitable separation method is _ _ _ _.
(a) atmospheric distillation (b) extraction (c) fractionation (d) vacuum distillation.
46, can use sublimation method to purify solid organic compounds must have one of the conditions is _ _ _ _ _.
(a) easy to decompose at high temperature; (b) high melting point; (c) high steam pressure; Low melting point.
47, the following mixed solvents should not be used for recrystallization is _ _ _ _ _.
(a) water-ethanol (b) water-acetone (c) methanol -* * * (d) 95% ethanol-petroleum ether.
48, laboratory vacuum distillation to purify liquid compounds, the receiver can choose _ _ _ _ _ _.
(a) conical flask (b) round bottom flask (c) flat bottom flask (d) volumetric flask
49, after drying with desiccant, liquid organic matter clarified, indicating that liquid organic matter _ _ _ _ _.
(a) No water; (b) There is still water; This does not mean that there is no water.
50, steam distillation, distillate thermometer reading is _ _ _ _ _.
(a) slightly higher than the boiling point of water; (b) equal to the boiling point of water; (c) lower than the boiling point of water.
5 1. In general, the atomic absorption spectrum is more sensitive than the atomic emission spectrum, because _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
52. The most suitable method to determine the functional groups of organic compounds is _ _ _ _ _.
(a) infrared spectroscopy (b) mass spectrometry (C)X-ray diffraction (d) chromatography.
53, with 220MHz proton (1H) to do nuclear magnetic resonance experiment, magnetic induction intensity (b) should be _ _ _ _ _ _ _ _ _ t.
(A)5. 168(B) 10.336(C) 15.780(D) 18.600
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