CaC_2(s) + 2H_20(l) rightarrow Ca(OH)_2(zq) + C_2H_2(g) Calculate delta H for th
ID: 967104 • Letter: C
Question
CaC_2(s) + 2H_20(l) rightarrow Ca(OH)_2(zq) + C_2H_2(g) Calculate delta H for the above reaction from the following data: Wolfgang Amadeus Mo/art died at the age of 35 after battling an illness for three months. Some suspected that he Mas being poisoned by a rival, but it is now believed that he had been accidentally poisoned by an antimony compound prescribed by doctors. Years later, Antonio Salieri, a contemporary composer and rival, while suffering from senility, is said to have confessed to murdering Mozart. However, he did not have access to Mozart to commit this crime. Antimony is determined by monitoring light emitted from an 1CP at 206.8 nm. Calculate the energy and frequency corresponding to this wavelength.Explanation / Answer
if given equations were numbered 1,2,3,4,5
then - eq(1) + eq(2) -eq(3) -eq(4) + 2 eq( 5) gives our required equation
( - eq 1 means we add reverse of eq1 , )
CaC2 --> Ca + 2C
Ca + 1/2 O2 -----> CaO
CaO + H2O ---> Ca(OH)2
2CO2 + H2O -----> C2H2 + 5/2 O2
2C + 2O2 ---> 2CO2
--------------------------------------------------------------
CaC2 + 2H2O ---> Ca(OH)2 + C2H2
dH = 62.8 +( -635.5) -(653.1) -(-1300) + 2( -393.5)
= -712.8 KJ/mol
2) wavelength = 206.8 nm = 206.8 x 10^ -9 m
frequency = c/lamda = (3 x 10^ 8) / ( 206.8x10^ -9) = 1.45 x 10^ -15
E = h x v = 6.625 x 10^ -34 x 1.45 x 10^ -15 = 9.6 x 10^ -19 Joules