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(II) Compare the value for the density of water vapor at exactly 100掳C and 1 atm (Table 10鈥�1) with the value predicted from the ideal gas law. Why would you expect a difference?

Question 36:(III) A sealed test tube traps of air at a pressure of 1.00 atm and temperature of 18掳C. The test tube鈥檚 stopper has a diameter of 1.50 cm and will 鈥減op off鈥� the test tube if a net upward force of 10.0 N is applied to it. To what temperature would you have to heat the trapped air in order to 鈥減op off鈥� the stopper? Assume the air surrounding the test tube is always at a pressure of 1.00 atm.

Question 37:(III) An air bubble at the bottom of a lake 41.0 m deep has a volume of\({\bf{1}}{\bf{.00}}\;{\bf{c}}{{\bf{m}}^{\bf{3}}}\). If the temperature at the bottom is 5.5掳C and at the top 18.5掳C, what is the radius of the bubble just before it reaches the surface?

Calculate the number of molecules/m³in an ideal gas at STP.

Question 39:(I) How many moles of water are there in 1.000 L at STP? How many molecules?

Question: Which is larger, 1 C掳 or 1 F? Explain why.

Question40:(II) Estimate the number of (a) moles and (b) molecules of water in all the Earth鈥檚 oceans. Assume water covers 75% of the Earth to an average depth of 3 km.

Question 41:(II) The lowest attainablepressure using the best available vacuum techniques is about \({\bf{1}}{{\bf{0}}^{{\bf{ - 12}}}}\;{\bf{N/}}{{\bf{m}}^{\bf{2}}}\). At such a pressure, how many molecules are there per cm³ at 0掳C?

Calculate the rms speed of helium atoms near the surface of the sun at a temperature of about 6000K.

Question: (I)A gas is at 20掳C. To what temperature must it be raised to triple the rms speed of its molecules?