4(a) A car tyre (an automobile tire) was in ated to a pressure of 24 lb in−2(1.00 atm = 14.7 lb in−2) on a winter’s day when the temperature was −5 °C. What pressure will be found, assuming no leaks have occurred and that the volume is constant, on a subsequent summer’s day when the temperature is 35 °C? What complications should be taken into account in practice? (b) A sample of hydrogen gas was found to have a pressure of 125 kPa when the temperature was 23 °C. What can its pressure be expected to be when the temperature is 11 °C?

5.(a) Assume for the moment that air consist of 80.00% nitrogen and 20.00% oxygen byvolume. Use these figures and typical values for temperature and pressure (1.000atm, 25.0 ºC) to calculate the density of air. (b) This calculation affords a good approximation of the density of air at sea level.However, your lab is at an altitude approximately 777 meters (2550 feet). Knowingthis, will the density of air in you lab be higher or lower than the value you justcalculated? Why? (c) Besides altitude, what else affects the atmospheric pressure? Where could you findthe actual atmospheric pressure at the time of the experiment?

(a) An ideal gas occupies a volume of 2.2 cm3 at 20°C and atmospheric pressure. Determine the number of molecules of gas in the container. (b) If the pressure of the 2.2-cm3 volume is reduced to 2.6 ✕ 10−11 Pa (an extremely good vacuum) while the temperature remains constant, how many moles of gas remain in the container?

4. (A) Indicate following statements as True (T) or False (F): (a) Higher the molar mass of a gas, faster its diffusion is. (b) Graham's law states that the rate of diffusion or effusion of a gas is inversely proportional to the square root of its molar mass. (c) When NH3(g) and HCI(g) react to form NH,Cl(s), a blue precipitate is observed. (d) Diffusion is the process whereby gaseous atoms and molecules are transferred from regions of relatively low concentration to regions of relatively high concentration. (e) The diffusion rate of a gas depends on the increase or decrease in concentration from one point to another (concentration gradient), the amount of surface area available for diffusion, and the distance the gas particles must travel. (B) If CH4(g) and C4HS(g) are released simultaneously at the left and right ends of a glass tube with 50 cm length, respectively, at what distance from the left end of the tube will they meet? (CH4: 16 g/mol, C4H8: 56 g/mol) 50 cm CH,- - CH,

The partial pressure of water vapor in saturated air at 27 °C is 3.51×10-2 atm. (a) How many molecules of water are in 1.21 cm3 of saturated air at 27 °C?   (b) What volume of saturated air at 27 °C contains 0.408 mol of water?

Lithium metal of mass 20.0 g is dropped into a beaker of water, producing hydrogen gasand an aqueous lithium hydroxide solution.2 Li (s) + 2 H2O (l) → 2 LiOH (aq) + H2 (g)What volume of hydrogen gas is produced if the temperature is 30 oC and the pressure is125 kPa?

(a) A rigid tank contains 1.60 moles of helium, which can be treated as an ideal gas, at a pressure of 28.0 atm. While the tank and gas maintain a constant volume and temperature, a number of moles are removed from the tank, reducing the pressure to 5.00 atm. How many moles are removed? mol (b) What If? In a separate experiment beginning from the same initial conditions, including a temperature T, of 25.0°C, half the number of moles found in part (a) are withdrawn while the temperature is allowed to vary and the pressure undergoes the same change from 28.0 atm to 5.00 atm. What is the final temperature (in °C) of the gas? °C

+7 (A) 15.2 L B) 0 C) +3 D) -2 19. 68.1 g solid CaCO3 is mixed with excess HC1. What is the volume of CO2 will be collected at 0.0 °C, and 1 atm. (Molar mass CaCO3 = 100.08 g/mol, CO₂ = 44.1 g/mol CaCO3 (s) + 2 HCl(aq) → H₂O (1) +CaCl2 (aq) + CO₂(g) C) OL B) 29.9 L C D) 155 L 20. A gas sample has an initial volume of 0.500 L and initial pressure of 1.0 atm. Wha the volume when the pressure of the sample is decreased to 0.50 atm? Assume the temperature and number of moles of the gas are constant. P₁V₁ = P₂1 A) .0 L B) 0.025 L

The gas in the discharge cell of a laser contains (in mole percent) 11% CO2, 5.3% N2, and 84% He. (a) What is the molar mass of this mixture? (b) Calculate the density of this gas mixture at 328C and 758 mm Hg. (c) What is the ratio of the density of this gas to that of air (MM air = 29.0 g/mol) at the same conditions

A 0.517 g sample of a metal, M, reacts completely with sulfuric acid according to M(s)+H2SO4(aq)⟶MSO4(aq)+H2(g) A volume of 235 mL of hydrogen is collected over water; the water level in the collecting vessel is the same as the outside level. Atmospheric pressure is 756.0 Torr, and the temperature is 25 °C. The vapor pressure of water at 25 °C is 23.8 Torr. Calculate the molar mass of the metal.