Question
www.awc.aleks.com O THERMOCHEMISTRY Calculating molar heat capacity Unread iba ad: Breaking a sive tradition or p... t.com e ad agencies to te whether they're. A chemist carefully measures the amount of heat needed to raise the temperature of a 405.0 mg sample of C4H,O experiment shows that 13.0 J of heat are needed. What can the chemist report for the molar heat capacity of C,H,O significant digits from-7 ? Round your answer to 3 9 to 11.6 . The 10 to house prices already near botto... ar.com al estate prices nue to drop following J mol K ld Trump sides with ocrats on debt ceili... tar.com nst the wishes of his Aa y, Donald Trump.. gle Ads gle.com our business Google all ove...
Explanation / Answer
Heat energy used = number of moles x molar heat capacity x change in temperature
heat energy used = 13 J
change in temperature = 19.5 K (I have taken the initial temperature as -7.9)
Number of moles = mass/ molar mass = 0.405/72 = 0.005625
(molar mass of C4H8O is 72 g/mole)
substitute in the above equation
molar heat capacity = 13/(0.005625 x 19.5) = 118.51 J/K.moles