Question

the volume occupied by the O^2 gas at 27° Celsius and 740 mm of pressure

Answer 1

4 answers · Chemistry

Answers

Simply use this variation on the ideal gas equation (PV=nRT)

PV = mRT / M ....... n is replaced by mass / molar mass

V = mRT / PM ....... solve for V

V = 3.5g x 62.36 Ltorr/molK x 300.K / 740 torr / 32.0g/mol

V = 2.8L ............. to two significant digits

By using a single equation and not computing moles and then substituting it into a second calculation we can avoid mistakes like N3XV$81 made which caused his answer to be off by a factor of 10. In addition, the answer can be expressed to only two significant digits based on the precision of the given data. 3.5 g and 740 torr are expressed to only two significant digits. N3XV$81's answer is given to five significant digits, which is incorrect.