[b][size=4]For nos. 1-5: Please refer to the stem provided.[/size][/b]



[size=4]A 40.0-gram gas sample occupies 11.2 liters at standard temperature and pressure (STP: 1 atm, 273.15 K). Under these conditions, the product of pressure and volume (PV) represents a direct measure of the total internal kinetic energy of the gas molecules. Based on its physical properties, the substance is presumed to be a noble gas with a naturally occurring isotopic composition.[/size]



[size=4]1. How many moles of gas are present in the sample at STP? (Note: 1 mol of any ideal gas at STP = 22.4 L)[/size]

[size=4]Based on the given mass and computed number of moles, what is the molar mass of the gas? [/size]

[size=4]Which noble gas corresponds most closely to the calculated molar mass?[/size]

[size=4]Calculate the pressure–volume (PV) product in joules and identify what it represents. (Note: 1 L·atm = 101.325 J)[/size]

[size=4]If the internal energy of an ideal monatomic gas is given by U = 3/2 nRT, which statement correctly describes the relationship between U and PV for this sample?[/size]