Gases and Their Properties of Chemistry

АР Chemistry Gases and Their Properties PRAC 1. 2. А pressure of 745 mmHg corresponds to _ kPa. 7. А 31.О mL sample of gas is collected at а 55.89 kPa 99.3 kPa temperature of 37 °С and pressure of 720 mmHg. 0.980 kPa 745 kPa What is its volume at 17 °С and 580 mmHg. Liquid nitrogen has а bo�Hng point of -196 this coпesponds to ... а) ·- 469К а) 23 mL d) 41 mL Ь) 27 mL . е) 58 mL 36 mL с) 153К 77К d) 469К 8. The coldest possiЫe temperature of а gas is: а) О 0 С 3. ICE TES Ь) 273К с) -273К -273 °С 1.20 atm is the same pressure as: а) 1.2 mmHg d) 9. The pressure of 4.0 L of an ideal gas in а flexiЫe Ь) 760 mmHg container is decreased to one-third of its original с) 912 mmHg pressure and its absolute temperature is decreased Ьу one-half. The voluшe tl1en is 4. For an ideal gas, which pair of variaЫes are а) 1.0 L Ь) 4.0 L .О L d) 8.0 L е) 24 L inversely proportional to each other (if all other factors remain constant)? P,V с) V, Т Ь) Р, Т d) n, Р 1О. А given шass of gas in а rigid container is heated froш 100 °С to 0 С. Which of the following happen to the pressure of the gas? The pressure will ... 5. А gas would act most ideal at 1.0 atm 273К а) decrease Ьу а factor increase а factor Ь) 10 atm and 546К increase Ьу а factor less than three. с) 10 atm and 273К d) decrease Ьу а factor greater than thr�e. 0.5 atm and 546К е) 0.5 atm and 273К 6. 11. What is the pressure exerted Ьу some nitrogen gas collected in а tube filled with water on а day when One mole of hydrogen, Н2, occupies 61.2 L at the room temperature is 18.0 °С and the room а) 100 °С and 1.00 atm pressure is 750.0 mmHg? [The partial pressure of Ь) 200 °С and 1.00 atm water at 18 °С is 15.5 mmHg.] с) О С and 0.500 atm а) 15.5 mmHg d) 760.0 mmHg d) 50 °С and 0.500 atm Ь) 750.0 mmHg е) 732.0 mmHg 100 °С and .500 atm 734.5 mmHg 0 1 АР Chemistry The Gas Laws PRESSURE UNITS 1 atm = 760 mmHg = 760 tor:r = 101.З kPa = 14.7 psi Background: Pressure is defined as Force / Area such as pounds per square inch (psi). The weight of air pushing down per square inch is 14.7 pounds per square inch or 14.7 psi. А barometer can Ье used to measure pressure. А column ofmercury (Hg) thatis 0.760 meter (760 mm) tall has the same weight as а column ofair from sea level to the edge ofthe stratosphere. The neight ofthis column is а good measure ofair pressure... 760 mmHg. Evangelista Torricelli did а lot ofexperiments with pressure and so 1 mmHg is also called 1 torr. So, air pressure has а value of760 to.r.r. This amount ofpressure is also called 1 atm (one atmosphere) because it IS the atmosphere. In metric units, pressure in Newtons (force) per square meter (area). One Newton is not very much pressure ... about the weight of а small apple (get it ... apple ... Newton) ... and if that force is exerted over а square meter, the amount ofpressure is very small and called а pascal (Ра). It is more useful to talk ofkilopascals (kPa) which would Ье the weight of1ООО small apples exerted over а square meter. Air pressure is equal to 101.3 kPa. Since each ofthese values (see the top ofthe page) represent the same amount ofpressure, any two ofthem cart Ье used as а conversion factor. Уou can convert one pressure unit into another. -----------------------------------101.ЗkРа Example: What is 515 mmHg in kPa? 515 mmHg х ---- = 68.6440789 kPa = 68.4 kPa 760mmHg ProЫems: 5. 522 torr into kPa К 7G,C) 6. l.l0 atm into psi Х /(о. (fS' :: I 7. 800. mmHg into atm Х о. '5 / g, (i 4. 0.729 atm into mmHg ,>( = �.:::. 7 f.D 6,v\,n /.о� = 8. 125 kPa into torr )( r