化学与可持续发展高中化学竞赛试题Chemistry and sustainable development high school chemistry competi

The B. and do not need to be compared to ABER process under the condition of high temperature, can save a lot of energy C.

Ammonia is usually ABER process iron as catalyst

D. new catalyst reduces the energy required for the reaction

24. the following statement is correct

The effective component of bleaching powder is calcium chloride and calcium hypochlorite

Strict implementation of motor vehicle exhaust emission standards is conducive to the prevention of air pollution

The use of sulfur dioxide whitening food is harmful to human health

4. Disinfection of tap water with chlorine can produce organic chlorides harmful to human body

The wastewater containing rich nitrogen and phosphorus nutrients produced by food factories can be transported to reservoirs and lakes for a long time to facilitate fish culture

A., B., C., D.

25.U (uranium) is an important raw material for nuclear

industry, familiar with +4 and +6 valence. Uranyl nitrate [UO2 (NO3) 2] heating can be decomposed to: UO2 (NO3) 2, UXO y+NO2+O2, at 600 K, the gas products set in a test tube and pour water, water filled tube. The chemical formula for the formation of uranium is ()

A.UO2 B.UO3 C.2UO2? UO3 D.UO2? 2UO3

26. at a certain temperature, a certain amount of Na2 O2 is added to the saturated caustic soda solution to recover to the original temperature after sufficient reaction

The C (Na+) increases in A. solution, and the pH increases with the release of B. from O2 solution, and the O2 emission occurs

The number of Na+ in C. solution decreases, and the O2 released from D. solution remains unchanged with H2 emission from pH solution

27. from some properties (CN) 2 and C12, NH3 and H2O, NH4+ and H3 O+, NH2 22 and OH- are similar within each group,

Accordingly, it is correct to judge that the following reactions are correct

1 (CN) 2+2OH =OCN +CN +H2O 2Na+2NH3=2NaNH2+H2 = 2

The CuO+2NH4Cl=CuCl2+2NH3+H2O NH4 C1+NaNH2=2NH3 = +NaCl

A., B., C., and D. are all correct

28. a chemical team designed the following experimental scheme to determine the mass fraction of copper in a certain copper aluminum mixture:

Solution I: copper aluminum mixture - adding a certain concentration of a solution to determine the volume of gas generated

Scheme II: copper aluminum mixture - adding a certain amount of a certain concentration of solution, after filtration, washing to determine the quality of the remaining solids

The following incorrect judgments are ()

A. solution A and B can be hydrochloric acid or NaOH solution B. solution, B can not use concentrated nitric acid

Dilute nitric acid D. can be used for A and B in C. solution, and the scheme II in laboratory is more convenient to implement

29.1 g magnesium powder burns in oxygen, weight gain of 0.64 g, while the combustion in the air, the weight gain of less than 0.64 g, the reason is ()

A. powder in the air without complete combustion of combustion, B. Magnesium Oxide not all weighing

C. magnesium reacts with nitrogen in the air and reacts with carbon dioxide when D. magnesium is burned in the air

30. there is a KOH solid which is exposed in the air. The water

content is 2.8%, K2 C03 7.2% is determined by analysis, and the sample L G is reacted with 1 mol / L hydrochloric acid 100 mI,

The neutralization of excess hydrochloric acid was carried out with 37% KOH solution with mass fraction of 5 g. The obtained solution was evaporated and dried. The quality of the obtained solid was ()

A.3.73 g B.4.00 g C.4.50 g D.7.45 G

Two, choice (each item has 1-2 options to do. A total of 20 items, each item of 2 points, a total of 40 points. )

31. scientists proposed that silicon is \in twenty-first Century\which is mainly due to the silicon as a semiconductor material plays an important role in the process of solar power generation. The following statement about silicon is correct

A. is abundant in silicon in nature. B. contains a large amount of elemental silicon in nature

C. high purity silicon is used to make computer chips. The main component of D. optical fiber is Si

32. the following statements are correct

A. to remind people in the use of concentrated H2S04 to pay great attention to safety, storage capacity of H2 S04 thick

The right logo is attached to the instrument

A.H+ B.OH - C.Cl - D.Na ten

34. studies show that O.1 mol / L CuS04 solution and 0.1 mol / L NaOH solution are mixed at a volume ratio of 2:3 at room temperature

After sufficient reaction, the pH of the solution was 7. Accordingly, the following statement is correct

A. copper sulfate and sodium hydroxide, generating blue hydroxide

The above phenomenon in B. must be the error of solution concentration or volume record

C. copper sulfate and sodium hydroxide, the product is not necessarily the case

The reaction of D. may be 4CuS04+6NaOH=Cu4 (OH) 6S04+3Na2 S04 D.

The possible reaction is 4CuS04+6NaOH=Cu4 (OH) 6S04+3Na2S04

35. it is pointed out that the vapor density of anhydrous aluminium chloride at different temperatures under standard atmospheric pressure is:

T (c) 200600800 D (g / mL) 6.8 x 10 - 32.65 x 10 - 31.51 x 10 - 3 gas mole (L / mo1) 38.8, 71.6 88 visible, the chemical form of anhydrous aluminium chloride in the form of anhydrous