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TALIGAMAN NATIONAL HIGH SCHOOLButuan CitySCIENCE III

FOURTH PERIODICAL EXAMINATION(S.Y. 2013-2014)

_______________________________________________________________________ Choose the letter that corresponds to your answer.

1. Which of the following does not describe a gas?a. compressible c. no fixed volume;b. widely separated d. higher density

2. In comparison to solid and liquids, gases have_________________densities due to the amount of spacebetween the molecules.

a. no b. lower c. high d. higher 3. According to Kinetic Molecular Theory, kinetic energy of a substance *a. increases during fusion c. increases with increasing temperatureb. decreases during conduction d. decreases with increasing temperature

4. What happens to the average kinetic energy of ideal gas molecules when the volume of gas is increased by decreasing the pressure at constant temperature?

a. Kinetic energy increase. c. Kinetic energy decreasesb. No change in kinetic energy d. Kinetic energy changes by a factor of 0.5

5. Which of the following assumptions of Kinetic Molecular Theory of gases is correct?a. Gas particles strongly attract each other.b. Gas particles travel in curved path.c. The volume of gas particles prevents random motion.d. Energy may be transferred between colliding particles.

6. The following are Postulates of Kinetic Molecular Theory.I. Gas molecules move in straight lines in all directions.II. Collisions with other molecules changes the direction of motion.III. Gas molecules occupy all regions of the container.

Why does a gas will evenly fill any container of any shape?a. I only b. II only c. III only d. I, II and III

7. What is the process of spreading out spontaneously to uniformly occupy a space?a. expansion b. volume c. diffusion d. pressure

8. In standard temperature and pressure (STP), the average kinetic energy of the molecules is proportional to the temperature of the gas in Kelvin. Temperature in Kelvin can be converted into degrees Celsius; by

a. dividing 273 from the temperature c. subtracting 273 from the temperatureb. multiplying 273 from the temperature d. adding 273 from the temperature

9. Which of the following will substantially change in volume if the pressure exerted on it is doubled?a. gas b. liquid c. solid d. all of these

10. If the volume of one mole of gas molecules remains constant, lowering the temperature will make the pressure?a. increase b. increase then decrease c. decrease d. decrease then increase

11. If the pressure of a confined gas at constant temperature is tripled, what will happen to thevolume?a. the volume will be tripled c. the volume will remain unchangedb. the volume will be reduced to one third the original d. the volume will be doubled

12. The volume of a mole of any ideal gas varies ________ at constant pressure.a. directly with the radius of glass moleculesb. inversely with the radius of the gas moleculesc. directly with the Kelvin (absolute) temperatured. inversely with the Kelvin (absolute) temperature

13. For a fixed mass of gas at constant temperature, the volume of the gas, V is inversely proportional to its pressure, P. Which of the following mathematical equation expresses this relationship?

a. PV = constant c.

b. P = V d.

14. Which of the following indicates the amount of gas particles?a. 10.0 L b. 760 torr c. 273 K d. 3.0 mole of He

15. A sealed metal container was heated at constant volume and at constant amount of gas. What happened when pressure increased?

a. boiling point is the same c. boiling point increasesb. boiling point decreases d. boiling point cannot be determined

16. Given the equation P1V1 = P2V2? , which of the following is the formula for final temperature? T1 T2

a. T2 = P2 x V2 x T1 c. T2 = P1 x V1 x T1

P1 V1 P2 V2

b. T2 = P1 x V2 x T1 d. T2 = T1 x V1 x T1

P2 V1 P1 P2

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17. Which of the following laws made up the combined gas law ?a. Boyle’s Law, Gay - Lussac’s Law and Avogadro’s Lawb. Charles’ Law, Avogadro’s Law and Graham’s Lawc. Gay - Lussac’s Law, Charles Law and Boyle’s Lawd. Graham’s Law, Ideal Gas Law and Charles’ Law

18. A child’s balloon is filled with helium to give a volume of 5.0 L, in an air conditioned store at 21°C. The child takes the balloon outdoors where the air temperature is 38°C. What happens to the balloon?

a. the volume increases c. the volume decreasesb. there is no change in the volume d. the pressure will change

19. Hazel is blowing a balloon and its volume increases. What will happen if it is punctured?a. volume increases as some air leaks out c. volume decreases as some air leaks out

b. volume increases as more air is added d. volume decreases as some air is added20. At constant pressure, which curve below shows the relationship between the volume of an ideal gas and its absolute temperature?

a.A b. B c. C d. D

A B

Volume in CLiters

D

Temperature in Kelvin

21. Which plot describes the volume-pressure relationship in gases at constant T if V and P are the X and Y axes respectively?

22. Calculate the pressure of a gas if it has 500 mL of volume at 27 °C if there are 3 moles of the gas present. Convert the volume and temperature according to the units provided in the gas constant as follows;

R = 0.082 atm.L mole.K

a. 0.0133 atm b. 13.28 atm c. 147.6 atm d. 493.9 atm23. What happen to one’s lung when one relaxes?

a. Volume of lungs decreases causing air pressure in lungs to be greater than atmospheric pressure.b. Volume of lungs increases causing air pressure in lungs to be greater than atmospheric pressure.c. Temperature in lungs decreases causing air pressure in lungs to be greater than atmospheric pressure.d. Temperature in lungs decreases causing air pressure in lungs to be greater than atmospheric pressure.

24. Pressure cooker saves time. What happen when one cooks food in it?a. Water in the pressure cooker will boil at lower temperature than 100 °C and food cooks faster.b. Water in the pressure cooker will boil at lower temperature than 100 °C and food cooks slower.c. Water in the pressure cooker will boil at higher temperature than 100 °C and food cooks slower.d. Water in the pressure cooker will boil at higher temperature than 100 °C and food cooks faster.

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25. A syringe with a sealed tip contains 0.1 g of gas at room temperature. As the plunger of the syringe is pushed down, which of the statement does not happen?

a. The pressure of the gas increases. c. The molecules come closer to each other,b. The molecules move faster. d. The volume of the gas decreases.

26. What happens when a reaction takes place endothermically?a. The temperature of the system drops.b. The temperature of the surroundings drops.c. The temperature of the surroundings rises.d. The temperature of the surroundings is constant.

27. Which of the following changes is exothermic?a. steaming of fish c. melting of iceb. photosynthesis in plants d. burning of alcohol

28. In industry, catalysts are added to chemical reaction. What will be the correct statement below that best describes the role of catalyst in a chemical reaction?

a. it increases the temperature of reaction c. it increases the amount of products formedb. it enables the products to be separated d. it increases the speed of formation of products

29. Which of the following laws states that the total mass of the reactants is equal to the total mass of the product?a. Law of definite composition c. Law of conservation of massb. Law of conservation of energy d. Law of inertia

30. Dalton’s Atomic Theory explains the laws of chemical changes. Which of Dalton’s assumptions explains the Law of Conservation of Mass?

a. An atom is the smallest particle of an element.b. In ordinary chemical reactions, no new atoms are created and no old ones are destroyed.c. Atoms of a given element have the same properties of size, shape and mass.d. Atoms combine in ratios of small whole numbers.

31. The atomic mass of carbon is 12 amu while that of hydrogen is 1 amu. The compound methane has the formula CH 4

and the molar mass is 16 g/mole. What is the percentage composition of CH4?a. 50% C; 50% H c. 75% C; 25% Hb. 12% C; 16% H d. 90% C; 10% H

32. What is the chemical formula of the compound formed when Mg reacts with S?a. MgS2 c. MgSb. Mg2 d. Mg2S3

33. What is the correct formula of iron(III) sulfate?a. FeS c. Fe2(SO4)3

b. Fe3(SO4)2 d. FeSO4

34. What products form when potassium nitrate decomposes?a. Potassium nitrate and oxygen c. Potassium, oxygen and nitrogenb. Potassium nitrite and oxygen d. Potassium oxide and nitrogen

35. What type of reaction is shown by the equation below?Zn + 2 NaOH H2 + Na2ZnO2

a. combination c. single displacementb. decomposotion d. double replacement

FOR ITEMS 36-37 Given these two chemical reactions:I. 2 KNO3 2 KNO2 + O2

II. Fe + S FeS

36. What type of chemical reactions are in I?a. combination reaction c. double displacement reactionb. displacement reaction d. decomposition reaction

37. What type of chemical reactions are in II?a. combination reaction c. double displacement reactionb. displacement reaction d. decomposition reaction

38. What kind of reaction does the following general equation applies to? A + B AB

a. combination b. decomposition c. oxidation d. displacement

39. Which reaction below is not a combination reaction?a. 2 Na + Cl2 2 NaClb. 2 H2 + O2 2 H2Oc. 4 Fe + 3 O2 2 Fe2O3

d. CaCO3 CaO + CO2

40. Which of the following illustrates single replacement reaction?a. NH4OH + HCl NH4Cl + H2Ob. Pb(NO3)2 + 2 KBr PbBr2 + 2 KNO3

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c. Fe + CuSO4 FeSO4 + Cud. NaOH + HCl NaCl + HOH

41. Powdered copper when heated in an atmosphere of oxygen produces Copper (II) oxide according to the chemical equation:

2 Cu + O2 2 CuO

Which of the following conclusion will be formed about the mass of Copper (II) oxide that forms when all reactants were combined?

a. The same as the mass of copper that combines with oxygen.b. Twice the mass of oxygen that combines with copper.c. The sum of the masses of copper and oxygen that combined.d. The sum of twice the mass of copper and the mass of oxygen that combined

42. What is the first step in balancing chemical equation?a. Identify and write the word equation of its reactant and product.b. Writing the skeleton equation from the given word equation.c. Putting of coefficient numbers to the given compounds in both the reactant and the product.d. Determine the number of atoms of the elements that comprises the reactant and the product.

43. Which of the following statement is the final step in balancing chemical equation?a. Identify and write the word equation of its reactant and product.b. Writing the skeleton equation from the given word equation.c. Putting of coefficient numbers to the given compounds in both the reactant and the product.d. Determine the number of atoms of the elements that comprises the reactant and the product.

FOR ITEMS 44 -46Given a chemical equation: Pb(NO3)2 + 2 KBr PbBr2 + 2 KNO3?

44. Which of the following indicates that there are 6 atoms of Oxygen are present in the given chemical equation? a. Its subscript numbers c. its subscript numbers in the parenthesis b. Its coefficient numbers d. its subscript and coefficient numbers in the parenthesis

45. Which statement is true about the number of atoms of Bromine in the given equation?a. It is not correctly balanced with its corresponding number subscripts and coefficients.b. It is balanced with its corresponding number subscripts and coefficients.c. Its subscript number in the product is not equal to its coefficient numbers in the reactant.d. Its coefficient number in the reactant is not equal to its subscript number in the product.

46. What statement below is not true in describing the given equation?a. The given equation is a double replacement reaction.b. The given equation shows two elements displacing each other. c. The given equation is not correctly balanced.d. The given equation is correctly balanced.

47. The following equation are not correctly balance except one, What chemical equation below is correctly balanced?a. H2 + O2 H2O c. Mg + 2 HCl MgCl2b. SO2 + O2 SO3 d. Zn + 2 H2SO4 ZnSO4 + 2H2

48. Which of the following equations describes the complete balanced decomposition of potassium chlorate?

a. 2 KClO3 2 KCl + 2 O2 c. 2 KClO2 2 KCl + 4 O2

b. 2 KClO3 2 KCl + 3 O2 d. 2 KClO 2 KCl + O2

49. Which is the correct coefficient of oxygen in the equation C3H8 + O2 3 CO2 + 4 H2Oa. 3 b. 4 c. 5 d. 6

50. Which of the following is not correctly balanced?

a. NaCl + AgNO3 NaNO3 + AgCl c. N2 + H2 NH3

b. 4 Fe + 3O2 2 Fe2O3 d.2 Na + 2 H2O 2 NaOH + H2

GOOD LUCK!!!

TALIGAMAN NATIONAL HIGH SCHOOLButuan City

SCIENCE III

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THIRD PERIODICAL EXAMINATION(S.Y. 2013-2014)ANSWER KEY

1.D 11.b 21.A 31.C 41.C2.B 12.C 22.C 32.C 42.A3.C 13.A 23.A 33.C 43.C4.B 14.D 24.D 34.B 44.D5.D 15.C 25.B 35.C 45.B6.D 16.A 26.B 36.D 46.C7.C 17.C 27.D 37.A 47.D8.c 18.A 28.D 38.A 48.B9.A 19.C 29.C 39.D 49.C10.c 20.C 30.B 40.C 50.C

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TALIGAMAN NATIONAL HIGH SCHOOLButuan City

SCIENCE IIITHIRD PERIODICAL EXAMINATION

(S.Y. 2011-2012)ANSWER KEY

1.D 11.A 21.A 31.C 41.C2.B 12.C 22.C 32.C 42.A3.C 13.A 23.A 33.C 43.C4.B 14.D 24.D 34.B 44.D5.D 15.C 25.B 35.C 45.B6.D 16.A 26.B 36.D 46.C7.C 17.C 27.D 37.A 47.D8.D 18.A 28.D 38.A 48.B9.A 19.C 29.C 39.D 49.C10.A 20.C 30.B 40.C 50.C