Regents Review THE PHYSICAL BEHAVIOR OF MATTER

1. The phase change represented by the equation I 2 (s) -> I 2 (g) is called: A) Condensation B) Melting C) Sublimation D) Boiling  Correct Answer: Option C - Sublimation REGENTS REVIEW

2. What is the total number of joules of heat energy absorbed by 15 grams of water when it is heated from 30°C to 40°C? A) 630 B) 10 C) 43 D) 200  Correct Answer: Option A REGENTS REVIEW

3. Under the same conditions of temperature and pressure, a liquid differs from a gas because the particles of the liquid: A) Take the shape of the container they occupy B) Have no regular arrangement C) Are in constant straight-line motion D) Have stronger forces of attraction between them  Correct Answer: Option D - Have stronger forces of attraction between them REGENTS REVIEW

4. A solution in which the crystallizing rate of the solute equals the dissolving rate of the solute must be A) Unsaturated B) Saturated C) Concentrated D) Diluted  Correct Answer: Option B - Saturated REGENTS REVIEW

 5. The heat of fusion is defined as the energy required at constant temperature to change 1 unit mass of a A) Solid to gas B) Gas to liquid C) Solid to liquid D) Gas to solid  Correct Answer: Option C - Solid to liquid REGENTS REVIEW

6. The light produced by signs using neon gas results from electrons that are: A) Being lost by the neon atoms B) Moving from a lower to a higher principal energy level C) Being gained by the neon atoms D) Moving from a higher to a lower principal energy level  Correct Answer: Option D - Moving from a higher to a lower principal energy level REGENTS REVIEW

7. At standard temperature and pressure which gas is monoatomic? A) Nitrogen B) Neon C) chlorine D) Fluorine  Correct Answer: Option B - Neon REGENTS REVIEW

8. A student determined the heat of fusion of water to be J/g. If the accepted value is 333.3J/g, what is the student's percent error? A) 10% B) 9% C) 15% D) 30%  Correct Answer: Option A - 10% REGENTS REVIEW

9. What occurs as potassium nitrate is dissolved in a beaker of water, indicating that the process is endothermic? A) The temperature of the solution increases. B) The solution changes color. C) The temperature of the solution decreases. D) The solution gives off a gas.  Correct Answer: Option C - The temperature of the solution decreases. REGENTS REVIEW

10. To determine the density of an irregularly shaped object, a student immersed the object in 21.2 mL of water in a graduated cylinder, causing the level of the water to rise to 27.8 mL. If the object had a mass of 22.4 grams, what was the density of the object. A) 27 g / mL B) 3.4 g/ mL C) 6 g / mL D) 3.4 g / mL  Correct Answer: Option B g/ mL  Step 1:  D = M / V  First find the volume of the object = V = = 6.6 mL  M = 22.4 g  Step 2: Substitute the values of M and V in the equation - D = M / V  D = 22.4 g / 6.6 mL = 3.4 g / mL REGENTS REVIEW

11. At standard pressure, a certain compound has a low boiling point and is insoluble in water. At standard temperature and pressure, this compound most likely exists as: A) Ionic crystals B) Metallic crystals C) Nonpolar molecules D) Polar molecules  Correct Answer: Option C - Nonpolar molecules REGENTS REVIEW

13. The heat of fusion of a compound is 30 J/g. What is the total number of joules of heat that must be absorbed by a 15.0 gram sample to change the compound from a solid to a liquid at its melting point? A) 100 J/g B) 450 J/g C) 45 J/g D) 150 J/g  Correct Answer: Option B J/g REGENTS REVIEW

14. In which laboratory process could a student use 0.10 M NaOH(aq) to determine the concentration of an aqueous solution of HBr? A) Chromatography B) Decomposition of the solute C) Evaporation of the solvent D) Titration  Correct Answer: Option D - Titration REGENTS REVIEW

15. When 5 grams of KCl are dissolved in 50. grams of water at 25°C, the resulting mixture can be described as: A) Heterogeneous and unsaturated B) Heterogeneous and saturated C) Homogeneous and unsaturated D) Homogeneous and supersaturated  Correct Answer: Option C - Homogeneous and unsaturated  A mixture which has a uniform composition throughout is called a homogeneous mixture. KCl blends with water uniformly, making the resulting mixture homogeneous.  Saturation is defined as a point of maximum concentration or the point at which a solution of a substance can dissolve no more of that substance and additional amounts of it will appear as a precipitate.  However in the above question 50 grams of water does not reach a saturation point with 5 grams of KCl at 25 0 C. Hence, this solution is unsaturated. REGENTS REVIEW

16. The volume of a given mass of an ideal gas at constant pressure is A) Inversely proportional to the Kelvin temperature. B) Directly proportional to the Kelvin temperature. C) Inversely proportional to the Celsius temperature. D) Proportional to the Celsius temperature.  Correct Answer: Option B - Directly proportional to the Kelvin temperature. REGENTS REVIEW

17. Which substance cannot be decomposed into simpler substances? A) Methane B) Ammonia C) Methanol D) Aluminum  Correct Answer: Option D - Aluminum REGENTS REVIEW

19. A solid A is placed in contact with solid B. When will heat flow spontaneously from A to B? A) A is at a temperature of -25°C and B is at a temperature of -10°C B) A is at a temperature of 20°C and B is at a temperature of 20°C C) A is at a temperature of 20°C and B is at a temperature of 10°C D) A is at a temperature of 25°C and B is at a temperature of 30°C  Correct Answer: Option C - A is at a temperature of 20°C and B is at a temperature of 10°C REGENTS REVIEW

20. A temperature change from 60°C to 90°C has the least effect on the solubility of which of the following compositions? A) SO 2 (g) B) KClO 3 (s) C) NH 3 (aq) D) KCl(s)  Correct Answer: Option A - SO 2 (g) REGENTS REVIEW

22. A rigid cylinder with a movable piston contains a 2 L sample of neon gas at STP. What is the volume of this sample when its temperature is increased to 30°C while its pressure is decreased to 90 kilopascals? A) 2.5 L B) 1.6 L C) 3 L D) 0.25 L  Correct Answer: Option C - 3 L REGENTS REVIEW

23. Among the statements below; which one describes a chemical property? A) It dissolves in alcohol. B) Its crystals are a metallic gray. C) It reacts with hydrogen to form a gas. D) It forms a violet-colored gas.  Correct Answer: Option C - It reacts with hydrogen to form a gas. REGENTS REVIEW

24. Two solid samples each contain sulfur, oxygen, and sodium, only. These samples have the same color, melting point, density, and reaction with an aqueous barium chloride solution. It can be concluded that the two samples are the same A) Mixture B) Compound C) Solution D) Element  Correct Answer: Option B - Compound REGENTS REVIEW

25. How many joules of heat are absorbed when 70.0 grams of water is completely vaporized at its boiling point? A) 15,813 B) 23,300 C) 6,000 D) 158,130  Correct Answer: Option D - 158,130 REGENTS REVIEW

26. Among the equations below; which equation represents a physical change? A) H 2 O(s) kJ → H 2 O(l) B) 2H 2 (g) + O 2 (g) → 2H 2 O(g) kJ C) H 2 (g) + I 2 (g) kJ → 2HI(g) D) N 2 (g) + 2O 2 (g) kJ → 2NO 2 (g)  Correct Answer: Option A - H 2 O(s) kJ → H 2 O (l) REGENTS REVIEW

27. What Kelvin temperature is equal to 40°C? A) 298 K B) 100 K C) 200 K D) 313 K  Correct Answer: Option D K  0 0 C = 273 K  Hence, to change Celsius to Kelvin we can add 273 to the temperature measured in degree Celsius.  40°C = 313 K REGENTS REVIEW

28. In an experiment, a student found 21.6% by mass of water in a sample of BaCl 2.2H 2 O. The accepted value is 12.6%. What was the student's experimental percentage error? A) 3/18.6x100 B) 9/12.6x100 C) 9/21.6x100 D) 12.6/21.6x100  Correct Answer: Option B - 9/12.6x100  (Calculated value - accepted value)/ accepted value x 100 =  / 12.6 x 100 = 9 / 12.6 x 100 REGENTS REVIEW

30. Under which conditions of temperature and pressure does oxygen gas behave least like an ideal gas? A) Low temperature and low pressure B) Low temperature and high pressure C) High temperature and low pressure D) High temperature and high pressure  Correct Answer: Option B - Low temperature and high pressure REGENTS REVIEW