KÖZÉPSZINTŰ ÍRÁSBELI VIZSGA

Transcription

1 ÉRETTSÉGI VIZSGA május 14. KÉMIA ANGOL NYELVEN KÖZÉPSZINTŰ ÍRÁSBELI VIZSGA május 14. 8:00 Az írásbeli vizsga időtartama: 120 perc Pótlapok száma Tisztázati Piszkozati EMBERI ERŐFORRÁSOK MINISZTÉRIUMA Kémia angol nyelven középszint írásbeli vizsga 1412

2 Important information 120 minutes are allotted for the examination; the work has to be finished after 120 minutes. The questions can be answered in any order. For the solution of the problems, calculators without text-storage capability and fourplace logarithm tables can be used. The use of electronic or written support material other than mentioned above is not permitted. Read the introductory text of the questions carefully and keep its instructions. Write the answers in ink. If you cancel an answer or part of an answer, the cancelled work cannot be evaluated. You can get maximum points for the calculations only if the main steps of the solution are also indicated. Please, do not write anything into the grey squares. írásbeli vizsga / május 14.

3 1. Multiple choice Two substances should be compared below. Write the correct letter mark in the empty cells of the table. A) Aluminium B) Copper C) Both of them D) None of them 1. Light metal. 2. Malleable. 3. It becomes black if heated on air. 4. Objects made of this metal will not react with water under normal circumstances. 5. If it is reacted with hydrochloric acid, hydrogen gas evolves. 6. One of the components of brass. 7. It is used for the reduction of certain metal oxides (e.g., thermite reaction). 8. It is produced from bauxite in industry Panel question 8 points Compare calcium and sulphur, and their compounds based on the points given in the table. Calcium Sulphur Valence electron configuration of its atom in ground state Number of lone electrons The crystal lattice type of the element; The precise name of the chemical bond in the crystal The formation of its noble gas configuration ion from its atom (equation) The equation of its combustion The crystal lattice type of the product of combustion (in solid state); The precise name of the chemical bond in the crystal points írásbeli vizsga / május 14.

4 3. Case study Read the following text, and answer the questions based on the text and your knowledge in chemistry. Mineral water and medicinal water. Medicinal water in Hungary is such a mineral water that has a healing effect because of its physical properties or chemical composition, and which is referred to medicinal water based on decree. Those medicinal waters that keep their therapeutic effect over a long period of time can be sold in bottle, thus the patient can do the water cure in his home, as well. By the therapeutic use of medicinal waters containing several components, significant results can be reached. The daily liquid intake is about 2.5 litres (2.5 dm 3 ), but it is not advisable to drink so much of medicinal waters since some ions in too high quantities can enter our organism. Some elements and their physiological characteristics: Calcium: It is an important element of the bones and teeth, its deficiency can cause osteoporosis, its significant deficiency can cause muscle spasms. Daily requirement: 1 gram. Magnesium: It is also called anti-stress mineral, it supports our nervous system. It is an important element of the protein and carbohydrate metabolisms, it is necessary for the muscle functioning. Its deficiency may cause nervousness, insomnia, difficulty in concentration, muscle spasms, headache. The daily requirement is milligram, during pregnancy and breast-feeding 450 mg. However, high amount of magnesium ion makes the water bitter. Sodium: It takes part in the water regulation of the body. It plays an important role in the regulation of blood pressure, and the activity of certain enzymes. Its deficiency can cause weakness, nausea, muscle spasm, fainting. Daily requirement: 1-2 grams. Potassium: It takes part in the nervous stimulus together with sodium, therefore in the functioning of the nervous system and the muscles, and in the sustaining of the acid-base equilibrium and the osmotic pressure. The minimal daily requirement is estimated at 1.6 grams, the average daily intake may be between g. Iodine: It is a microelement important for the production of the hormones of the thyroid gland, it is essential for the proper functioning of thyroid gland. It is indispensable for the development of the fetus inside the uterus. Its deficiency leads to goitre. It can exclusively applied if prescribed by a physician, and under constant supervision. Daily requirement: 150 micrograms. Sulphate: Sulphate ion is primarily useful to avoid constipation. Sulphate ions are not absorbed from the intestines, thus they block the reabsorption of water for osmotic reasons if applied in large concentration, and thus diluting the content of the intestine. Composition of some medicinal and mineral water (the concentration of main ions in mg/dm 3 ) Medicinal waters Mineral waters Jódaqua Parád Mira Natur Theodora Aquarius water water Aqua Kékkúti Potassium ion Sodium ion Ammonium ion 20.4 Calcium ion Magnesium ion Chloride ion Bromide ion Iodide ion Hydrogencarbonate ion Sulphate ion Sulphide ion 6.2 Total mineral content (Sources: medaqua.hu/hu/gyogyviz) írásbeli vizsga / május 14.

5 1. Compare the mineral content of medical waters and plain mineral waters. 2. Write down the chemical symbol of that anion which is found in all medical and mineral waters listed. 3. The majority of natural water in Hungary does not contain iodine, therefore some iodide is added to table salt ensuring the daily iodine need. Theoretically, the iodine need could be satisfied by one of the medical waters listed in the table. Calculate how much of this water should be consumed daily, provided that this is the only source of iodine intake for our body. 4. Based on the text, which could be the most bitter among the waters listed? What unique physiological effect does it have (compared to the other five waters) if consumed in sufficient quantities? Give a reason to both of your answers. 5. a) Which of the plain mineral waters listed in the table is the hardest? Give a reason to your answer. b) Give an equation of the reaction taking place in the teapot, when this mineral water is used for tea making. 6. Demonstrate by calculation whether the daily requirement of calcium can be supplied by NaturAqua mineral water. 13 points írásbeli vizsga / május 14.

6 4. Single choice Write the symbol of the single correct answer of each question into the box on the righthand-side of the answers. 1. What volume of oxygen gas is needed for the complete combustion of 5.00 dm 3 carbon monoxide? A) 0.50 dm 3 B) 1.00 dm 3 C) 2.50 dm 3 D) 5.00 dm 3 E) 10.0 dm 3 2. Which of the following statements is true? A) Chlorine is dissolved better in water than in petrol. B) Graphite is dissolved not in water but in petrol. C) Table salt is dissolved well both in water and petrol. D) Sugar is dissolved better in petrol than in water. E) Ethyl alcohol is miscible both with water and petrol. 3. Which particle has a trigonal pyramidal shape and it contains 11 protons and 10 electrons? A) Ammonia molecule B) Ammonium ion C) Water molecule D) Hydronium ion E) Hydroxide ion 4. It is the characteristic of both DNA and RNA that A) the nucleotides are bound to each other by ester bond. B) they contain adenine, cytosine, guanine and thymine. C) the number of cytosine and guanine units are equal in each of them. D) the number of adenine and thymine units are equal in each of them. E) the number of cytosine and adenine units are equal in each of them. 5. Which is the compound whose molecule does not contain 6 delocalised electrons? A) Benzene. B) Toluene. C) Purine. D) Pyrrole. E) Pyridine. írásbeli vizsga / május 14.

7 6. In both the reversible reactions of hydrogen iodide production and ammonia synthesis the equilibrium can be shifted towards the product side by A) raising the temperature. B) increasing the pressure. C) decreasing the pressure. D) further addition of hydrogen. E) the use of a catalyst. 7. Which is the hygroscopic and strong oxidising agent that decomposes organic substances as well? A) Concentrated nitric acid solution. B) Concentrated sulphuric acid solution. C) Concentrated hydrochloric acid. D) Concentrated phosphoric acid solution. E) Concentrated sodium hydroxide solution. 8. Which statement is false? A) If sodium is burnt in chlorine gas, a white solid material is formed. B) If magnesium is burnt on air, a white solid material is formed. C) If iron is reacted with hydrochloric acid with exclusion of air, a yellowish solution is formed. D) If copper is placed into hydrochloric acid, no reaction occurs. E) If sodium is reacted with water containing phenolphthalein, a purple solution is formed. 9. Which statement is false in connection with catalysts? A) The equilibrium settles faster by the use of a catalyst. B) The reaction heat changes by the use of a catalyst. C) The catalyst does not influence the equilibrium concentration of the product. D) The catalyst increases the rate of a specific reaction(s). E) The catalyst is regained unchanged at the end of the reaction. 10. Which statement is true in connection with the transformation of organic compounds? A) Oxidation of ethyl alcohol results in acetic acid, its reduction results in ethanol. B) Methanol is produced by the reduction of formaldehyde. C) Acetic acid can be reduced to sodium acetate by sodium bicarbonate. D) Acetic acid and sodium ethanolate are produced by the alkaline hydrolysis of ethyl acetate. E) Addition of water to acetylene results in ethyl alcohol. 10 points írásbeli vizsga / május 14.

8 5. Alternative question In the following question only one version of the task should be solved depending on your field of interest. In the empty square below, the letter mark of the chosen question (A or B) should be indicated. If the box is left empty, and your choice is not evident from the testpaper, the solution of the first alternative question will be evaluated in any case. Letter mark of the chosen question: A) Consider the following hydrocarbons. a) Methane b) Ethene c) Ethyne d) Isoprene e) Heptane f) Benzene Give the letter mark of the appropriate hydrocarbon(s) for each question, and then answer the additional questions, too. 1. The main component of natural gas:. 2. One of the components of petrol:. How does the increasing amount of this substance change the octane number of petrol? 3. Highly carcinogenic compound:. 4. It is a liquid compound at 25 C and standard atmospheric pressure: Burns with a sooty flame in air:. 6. Reacts with chlorine without the use of a catalyst in a substitution reaction:.. Write down an example with an equation. 7. Reacts with bromine without the use of a catalyst in an addition reaction: Write down an example with an equation. (Indicate the structural formulae in the equation.) 8. Reacts with bromine only if a catalyst is used and warmed:... Name the type of the reaction. 9. Artificial caoutchouc is synthesised from this compound in industry:. Write down the reaction reflecting the main equation of the synthesis (by flowchart or equation indicating the constitution of the reactant and the product), and name the reaction type. írásbeli vizsga / május 14.

9 B) The smaller size household PB gas tank contains 11.5 kg of a mixture consisting of propane and butane, in which the butane content is 60.0 percent by mass. Its price was 5175 Ft in August a) Write down the equation of the combustion of propane and butane (resulting in water as steam) and calculate the reaction heat in both cases. b) Calculate the amount of heat liberated by the combustion of the complete content of one PB gas tank. c) Calculate how much does the heating of a house cost, which has an energy demand of 1000 MJ per month (and it is covered solely by the combustion of PB gas). 15 points A standard Daniell cell is built up. 6. Analytical task a) Draw the cell diagram of the Daniell cell. Indicate the poles and the concentration of the electrolytes. b) What is the colour of each two electrode metals? c) One of the aqueous solutions of the electrodes has a colour. What is its colour? Which electrode of the galvanic cell is this? (Underline the correct one.) anode cathode d) Write down the equation of the electrode reaction taking place in the electrode chosen in question c) while the galvanic cell is in use. írásbeli vizsga / május 14.

10 e) Calculate the electromotive force of the standard Daniell cell. f) Based on the above, determine in which of the following experiments a reaction takes place. Underline the correct answer. copper plate is immersed into a zinc nitrate solution zinc plate is immersed into a copper(ii) nitrate solution Write down the equation of the reaction taking place. g) How does the mass of the metal plate change during the reaction? Give a reason to your answer. 7. Calculation 13 points A factory releases 1000 m 3 wastewater daily, which contains a strong acid and its ph is (Consider the solution as pure hydrochloric acid solution for the calculation.) This solution has to be neutralised before discharging it into the canal. a) Would quicklime or limestone be safer for neutralisation? Give a reason to your answer, and calculate the daily need for the neutralisation. b) Another factory in the neighbourhood releases 3000 m 3 of ph = 9.00 strongly alkaline wastewater daily. (Consider this solution as a NaOH solution for the calculation.) Which wastewater and in what percentage is left not neutralised daily if the two wastewaters are mixed in a common tank? 12 points írásbeli vizsga / május 14.

11 8. Analytical task and calculation Bioethanol is synthesised from many different plants as an alternative fuel. The starch of plant origin or the cellulose fibres are excellent for this purpose. After the hydrolysis of the polysaccharides, the alcohol is produced by fermentation. (The density of water-free ethanol is g/cm 3.) a) Write down the molecular formula of cellulose. b) Name the monosaccharide produced during the hydrolysis of cellulose. c) Calculate how many kilograms of monosaccharide can be obtained theoretically from the hydrolysis of 1.00 kg of cellulose. d) Write down the equation of the fermentation of the monosaccharide into ethanol. e) A technological model experiments indicated that 65 cm 3 of bioethanol can be produced from 100 g of starch. What is the percentage of loss by which bioethanol can be synthesised in this model experiment? 15 points írásbeli vizsga / május 14.

12 maximum points points achieved 1. Multiple choice 8 2. Panel question Case study Single choice Alternative question Analytical task Calculation Analytical task and calculation 15 Score of the written exam 100 correcting teacher date Test/Feladatsor achieved score rounded to whole numbers/elért pontszám egész számra kerekítve whole points written in the program/ programba beírt egész pontszám marking teacher/javító tanár notary/jegyző date/dátum date/dátum írásbeli vizsga / május 14.